Contents
- What are hormones
What are hormones
If the body is to function as an integrated whole, its organs must communicate with each other and coordinate their activities. In humans, two such systems are especially prominent—the nervous and endocrine systems, which communicate with neurotransmitters and hormones, respectively. The nervous and endocrine systems act together to coordinate functions of all body systems. The endocrine system is a series of glands that produce and secrete hormones that the body uses for a wide range of functions.
Major hormone-producing endocrine glands are:
- Pineal gland,
- Hypothalamus,
- Pituitary gland (anterior and posterior pituitary),
- Thymus,
- Thyroid gland,
- Parathyroid glands,
- Adrenal glands,
- Pancreas,
- Ovaries (women),
- Testes (men),
- Other hormone-producing cells in several other organs, e.g. stomach, small intestines, heart, placenta, skin, liver and kidneys.
Other hormone-producing cells
Thymosin, produced by the thymus gland, plays an important role in the development of the body’s immune system.
The lining of the stomach, the gastric mucosa, produces a hormone, called gastrin, in response to the presence of food in the stomach. This hormone stimulates the production of hydrochloric acid and the enzyme pepsin, which are used in the digestion of food.
The mucosa of the small intestine secretes the hormones secretin and cholecystokinin. Secreting stimulates the pancreas to produce a bicarbonate-rich fluid that neutralizes the stomach acid. Cholecystokinin stimulates contraction of the gallbladder, which releases bile. It also stimulates the pancreas to secrete digestive enzyme.
The heart also acts as an endocrine organ in addition to its major role of pumping blood. Special cells in the wall of the upper chambers of the heart, called atria, produce a hormone called atrial natriiuretic hormone or atriopeptin.
The placenta develops in the pregnant female as a source of nourishment and gas exchange for the developing fetus. It also serves as a temporary endocrine gland. One of the hormones it secretes is human chorionic gonadotropin, which signals the mother’s ovaries to secrete hormones to maintain the uterine lining so that it does not degenerate and slough off in menstruation.
Skin, Liver, and Kidneys: The skin, liver and kidneys work together to synthesize 1,25-diydroxyvitamin D (calcitriol), the active form of vitamin D, which helps maintain normal levels of calcium and phosphorus in the blood. In the skin, a molecule made from cholesterol is converted to vitamin D by exposure to ultraviolet rays from the sun. Vitamin D undergoes further chemical changes, first in the liver and then in the kidneys, to become calcitriol. Calcitriol acts on the intestine, kidneys, and bones to maintain normal levels of blood calcium and phosphorus.
Figure 1. Endocrine glands and functions
Figure 2. Hormones sources of production and control via the Hypothalamus with feedback control from the Endocrine glands
Note: ACTH= Adrenocorticotropic hormone; TSH= Thyroid stimulating hormone; GH= Growth hormone; PRL= Prolactin; FSH= Follicle-stimulating hormone; LH= Luteinizing hormone; MSH= Melanocyte-stimulating hormones; OXT= Oxytocin; ADH= Antidiuretic hormone (arginine vasopressin)
Hormones, in the strict sense, are chemical (protein) messengers that are transported by the bloodstream and stimulate physiological responses in cells of another tissue or target organ, often a considerable distance away. Certain hormones produced by the pituitary gland in the head, for example, act on organs as far away as the pelvic cavity.
Hormones are produced by the endocrine glands and are sent into the bloodstream to the various tissues in the body. They send signals to those tissues to tell them what they are supposed to do. When the glands do not produce the right amount of hormones, diseases develop that can affect many aspects of life.
Hormones control many different bodily functions, including:
- Respiration
- Heart rate
- Metabolism – digestion, elimination, breathing, blood circulation and maintaining body temperature
- Appetite
- Reproduction
- Sensory perception
- Sleep cycles
- Movement
- Sexual development
- Growth and development
- Mood
- Responses to stress and injury
- Bone and muscle strength
Hormones are powerful. It takes only a tiny amount to cause big changes in cells or even your whole body. That is why too much or too little of a certain hormone can be serious. Laboratory tests can measure the hormone levels in your blood, urine, or saliva. Your health care provider may perform these tests if you have symptoms of a hormone disorder. Home pregnancy tests are similar – they test for pregnancy hormones in your urine.
If your hormone levels are too high or too low, you may have a hormone disorder. Hormone diseases also occur if your body does not respond to hormones the way it is supposed to. Stress, infection and changes in your blood’s fluid and electrolyte balance can also influence hormone levels.
In the United States, the most common endocrine disease is diabetes. There are many others. They are usually treated by controlling how much hormone your body makes. Hormone supplements can help if the problem is too little of a hormone.
Hormones
Growth hormone (GH): Secreted by the anterior lobe of the pituitary gland; promotes general growth of all body tissues, including bone, mainly by stimulating production of insulin-like growth factors.
Insulin-like growth factors (IGFs): Secreted by the liver, bones, and other tissues on stimulation by growth hormone; promotes normal bone growth by
stimulating osteoblasts and by increasing the synthesis of proteins needed to build new bone.
Thyroid hormones (T3 and T4): Secreted by thyroid gland; promote normal bone growth by stimulating osteoblasts.
Insulin: Secreted by the pancreas; promotes normal bone growth by increasing the synthesis of bone proteins.
Sex hormones (estrogens and testosterone): Secreted by the ovaries in women (estrogens) and by the testes in men (testosterone); stimulate osteoblasts and promote the sudden “growth spurt” that occurs during the teenage years; shut down growth at the epiphyseal plates around age 18–21, causing lengthwise growth of bone to end; contribute to bone remodeling during adulthood by slowing bone resorption by osteoclasts and promoting bone deposition by osteoblasts.
Parathyroid hormone (PTH): Secreted by the parathyroid glands; promotes bone resorption by osteoclasts; enhances recovery of calcium ions from urine; promotes formation of the active form of vitamin D (calcitriol).
Calcitonin: Secreted by the thyroid gland; inhibits bone resorption by osteoclasts.
Factors that Affect Endocrine Function
Everyone’s body undergoes changes, some natural and some not, that can affect the way the endocrine system works. Some of the factors that affect endocrine organs include aging, certain diseases and conditions, stress, the environment, and genetics.
Aging
Despite age-related changes, the endocrine system functions well in most older people. However, some changes occur because of damage to cells during the aging process and genetically programmed cellular changes. These changes may alter the following:
- hormone production and secretion
- hormone metabolism (how quickly hormones are broken down and leave the body)
- hormone levels circulating in blood
- target cell or target tissue response to hormones
- rhythms in the body, such as the menstrual cycle
For example, increasing age is thought to be related to the development of type 2 diabetes, especially in people who might be at risk for this disorder. The aging process affects nearly every gland. With increasing age, the pituitary gland can become smaller and may not work as well. For example, production of growth hormone might decrease. Decreased growth hormone levels in older people might lead to problems such as decreased lean muscle, decreased heart function, and osteoporosis. Aging affects a woman’s ovaries and results in menopause, usually between 50 and 55 years of age. In menopause, the ovaries stop making estrogen and progesterone and no longer have a store of eggs. When this happens, menstrual periods stop.
Diseases and Conditions
Chronic diseases and other conditions may affect endocrine system function in several ways. After hormones produce their effects at their target organs, they are broken down (metabolized) into inactive molecules. The liver and kidneys are the main organs that break down hormones. The ability of the body to break down hormones may be decreased in people who have chronic heart, liver, or kidney disease.
Abnormal endocrine function can result from:
- congenital (birth) or genetic defects (see section on Genetics below)
- surgery, radiation, or some cancer treatments
- traumatic injuries
- cancerous and non-cancerous tumors
- infection
- autoimmune destruction (when the immune system turns against the body’s own organs and causes damage)
In general, abnormal endocrine function creates a hormone imbalance typified by too much or too little of a hormone. The underlying problem might be due to and endocrine gland making too much or too little of the hormone, or to a problem breaking down the hormone.
Stress
Physical or mental stressors can trigger a stress response. The stress response is complex and can influence heart, kidney, liver, and endocrine system function. Many factors can start the stress response, but physical stressors are most important. In order for the body to respond to, and cope with, physical stress, the adrenal glands make more cortisol. If the adrenal glands do not respond, this can be a life-threatening problem. Some medically important factors causing a stress response are
- trauma (severe injury) of any type
- severe illness or infection
- intense heat or cold
- surgical procedures
- serious diseases
- allergic reactions
Other types of stress include emotional, social, or economic, but these usually do not require the body to produce high levels of cortisol in order to survive the stress.
Environmental Factors
An environmental endocrine disrupting chemical is a substance outside of the body that may interfere with the normal function of the endocrine system. Some endocrine disrupting chemicals mimic natural hormone binding at the target cell receptor. (Binding occurs when a hormone attaches to a cell receptor, a part of the cell designed to respond to that particular hormone.) Endocrine disrupting chemicals can start the same processes that the natural hormone would start. Other endocrine disrupting chemicals block normal hormone binding and thereby prevent the effects of the natural hormones. Still other endocrine disrupting chemicals can directly interfere with the production, storage, release, transport, or elimination of natural hormones in the body. This can greatly affect the function of certain body systems.
Endocrine disrupting chemicals can affect people in many ways:
- disrupted sexual development
- decreased fertility
- birth defects
- reduced immune response
- neurological and behavioral changes, including reduced ability to handle stress
Genetics
Your endocrine system can be affected by genes. Genes are units of hereditary information passed from parent to child. Genes are contained in chromosomes. The normal number of chromosomes is 46 (23 pairs). Sometimes extra, missing, or damaged chromosomes can result in diseases or conditions that affect hormone production or function. The 23rd pair, for example, is the sex chromosome pair. A mother and father each contribute a sex chromosome to the child. Girls usually have two X chromosomes while boys have one X and one Y chromosome. Sometimes, however, a chromosome or piece of a chromosome may be missing. In Turner syndrome, only one normal X chromosome is present and this can cause poor growth and a problem with how the ovaries function. In another example, a child with Prader-Willi syndrome may be missing all or part of chromosome 15, which affects growth, metabolism, and puberty. Your genes also may place you at increased risk for certain diseases, such as breast cancer. Women who have inherited mutations in the BRCA1 or BRCA2 gene face a much higher risk of developing breast cancer and ovarian cancer compared with the general population.
Endocrine Disrupting Chemicals
Endocrine disrupting chemicals are substances in the environment (air, soil or water supply), food sources, personal care products, and manufactured products that may interfere with the normal function of your body’s endocrine system 1.
Endocrine disrupting chemicals, a broad category of compounds used in consumer products, electronics and agriculture, have been associated with a diverse array of health issues. These non-natural chemicals or mixtures of chemicals can mimic, block, or interfere with the way the body’s hormones work.
They have been linked to human health issues related to sperm quality, fertility, abnormalities in sex organs, endometriosis, early puberty, nervous system function, immune function, cancers, breathing problems, metabolic issues, obesity, heart health, growth, neurological and learning disabilities, and more.
Exposure to endocrine disrupting chemicals can happen anywhere and come from the air we breathe, the food we eat, and the water we drink. Endocrine disrupting chemicals can also enter the body through the skin and by transfer from mother to fetus (across the placenta) or mother to infant (via breast feeding) if a woman has endocrine disrupting chemicals in her body.
Examples of endocrine disrupting chemicals include bisphenol A (BPA), phthalates, pesticides, and pollutants such as dioxin and polychlorinated biphenyls (PCBs).
Endocrine disrupting chemicals Facts
Endocrine disrupting chemicals often disrupt the endocrine system by mimicking or interfering with a natural hormone. These “hormone mimics” can trick the hormone receptor into thinking the endocrine disrupting chemicals is the hormone, which can trigger abnormal processes in the body. Studies support a link between endocrine disrupting chemicals and harm to human health, but the cause-and-effect relationship is not yet fully understood. Still some endocrine disrupting chemicals are known to pose a threat to people who have excessive exposure to them.
Where are endocrine disrupting chemicals ?
- Industrial chemicals can leach into soil and groundwater and then make their way into the food chain and build up in fish, animals, and people
- Consumer products such as plastics, household chemicals, fabrics treated with flame retardants, cosmetics, lotions, products with fragrance, and anti-bacterial soaps
- Pesticides, fungicides, or industrial chemicals in the workplace The best way to avoid exposure is to check labels and avoid products with known endocrine disrupting chemicals.
Table 1. Some common endocrine disrupting chemicals (EDCs) and their uses include the following:
Common Endocrine Disrupting Chemicals | Used In |
Pesticides | Example EDCs: DDT, Chlorpyrifos, Atrazine, 2,4-D, Glyphosate |
Children’s Products | Example EDCs: Lead, Phthalates, Cadmium |
Industrial Solvents or Lubricants and Their Byproducts | Example EDCs: PCBs and Dioxins |
Plastics and Food Storage Materials | Example EDCs: BPA, Phthalates, Phenol |
Electronics and Building Materials | Example EDCs: Brominated Flame Retardants, PCBs |
Personal Care Products, Medical Tubing | Example EDCs: Phthalates, Parabens, UV Filters |
Anti-Bacterials | Example EDCs: Triclosan |
Textiles, Clothing | Example EDCs: Perfluorochemicals |
Where do endocrine disrupting chemicals impact your body ?
More research is needed, but scientists know endocrine disrupting chemicals affect:
Response to stress
- Neurological and behavioral changes
- Reduced ability to handle stress
Metabolism
- Industrial chemicals can interfere with thyroid function
Reproduction
- Virtually all classes of endocrine disrupting chemicals (DDT, BPA, phthalates, PCBs) can mimic or block effects of male and female sex hormones, affecting reproductive health
Growth and development
- Neural development
- Disrupted sexual development
- Weakened immune system
Avoiding endocrine disrupting chemicals
Even if some health effects are not fully proven, taking precautions is wise. Become familiar with endocrine disrupting chemicals to which you and your family may be exposed. Try to avoid unnecessary, preventable exposure to endocrine disrupting chemical-containing consumer products. Experts suggest avoiding microwaving food in plastics to avoid leaching of endocrine disrupting chemicals into food, choosing personal care products and cleaners that are unscented, and replacing older non-stick pans with newer, ceramic-coated ones. These precautions are especially important if you are pregnant or planning a family.
Plastic bottles
At the bottom of your plastic bottle, you’ll find a triangular shape with arrows with a number inside. Those numbers represent the type of plastic used in making the bottle. Plastics with recycling labels #1, #2 & #4 may be safer choices as they do not contain BPA. However, BPA is not the only endocrine disruptor in plastic so just because something is “BPA-free” does not mean that it is endocrine disrupting chemical-free. When possible, avoid disposable plastics.
How to balance hormones naturally
Changing Your Lifestyle
Some of the factors that affect endocrine organs include aging, certain diseases and conditions, stress, the environment, your diet, your body weight and genetics.
Adopting healthy habits — such as regular exercise and adequate sleep along with healthy eating — are important steps in restoring your hormones including the daily cortisol rhythms.
For example, being overweight or obese (too much body fat) can affect your hormones. And with modest weight loss you can improve your health.
If you are living with hormones imbalance, lifestyle is an important part of your treatment. It is very important that you eat a good balance of foods every day and exercise regularly. Managing your hormone imbalance also means taking medicine, if needed.
Healthy Eating
People with hormones imbalance does not require special foods. A healthy, balanced diet can come from everyday foods. Your doctor can refer you to a dietitian who can help you plan meals that taste great and are good for you.
If you have hormones imbalance, you should:
- Consume less than 10 percent of calories per day from added sugars.
- Consume less than 10 percent of calories per day from saturated fats.
- Consume less than 2,300 milligrams (mg) per day of sodium.
- If alcohol is consumed, it should be consumed in moderation—up to one drink per day for women and up to two drinks per day for men—and only by adults of legal drinking age.
- Choose foods that are low in fat and salt
- Choose foods that are high in fiber (such as beans, vegetables, and fruit)
- Eat foods from all food groups. The U.S. Department of Agriculture has plenty of information about choosing a balanced diet
- Lose weight if you need to by cutting down on how much you eat.
A healthy diet includes:
- For vitamins, minerals and fiber, eat at least 2 cups of fruits and 2½ cups of vegetables each day.
- Whole grains. Eat at least half of all grains as whole grains each day. Replace refined grains with whole-grain bread, cereal, pasta, brown rice or oats.
- At least two to three servings of fish per week.
- Three servings of low-fat or fat-free dairy products including low-fat or fat-free milk, yogurt or cheese.
- Five to 6 ounces of protein such as lean meat, chicken, turkey, fish, eggs, beans or peas and nuts.
- Two cups of fruits — fresh, frozen or canned without added sugar.
- Two-and-a-half cups of colorful vegetables — fresh, frozen or canned without added salt.
- At least 38 grams of fiber a day for younger men and 30 grams of fiber for women; 30 grams of fiber a day for men and women older than 50.
- Unsaturated fats such as oils, nuts and oil-based salad dressings in place of saturated fats including full-fat dairy foods, butter and high-fat sweets.
- 4,700 milligrams a day of potassium from fruits, vegetables, fish and milk.
For healthy bones and teeth, you need to eat a variety of calcium-rich foods every day. Calcium keeps bones strong and prevents osteoporosis, a bone disease in which the bones become weak and break easily. Some calcium-rich foods include low-fat or fat-free milk, yogurt and cheese, sardines, tofu (if made with calcium sulfate) and calcium-fortified foods including juices and cereals.
Women of childbearing age need to eat enough folic acid to decrease risk of birth defects. The requirement is at least 400 micrograms of folic acid a day. Be sure to consume adequate amounts of folic acid daily from fortified foods or supplements, in addition to food forms of folate from a varied diet. Citrus fruits, leafy greens, beans and peas naturally contain folate. There are many folic acid fortified foods such as cereals, rice and breads.
What and How much Should you Eat ?
For an average adult male who requires 2000 Calories (8368 kilojoules)
Note: 1 Calorie (kilocalories) = 4.184 kilojoules (kJ)
Because how much calories you eat and what food groups you need are highly dependent on your age, sex, and your level of physical activity. For the most accurate way calculate how much food and calories you need to eat per day from each food group >>> Go to the United States Department of Agriculture’s MyPlate Daily Checklist 2 >>> https://www.choosemyplate.gov/myplate-daily-checklist-input
Simply enter your age, sex, height, weight, and physical activity level to get a plan that’s right for you. The MyPlate Daily Checklist shows your food group targets – what and how much to eat within your calorie allowance.
Foods that balance hormones
An important part of maintaining a healthy weight and healthy lifestyle is to maintain energy balance is the amount of ENERGY OUT (physical activity) that you do. People who are more physically active burn more calories than those who are not as physically active.
- Vegetables
- Dark-green vegetables: All fresh, frozen, and canned dark-green leafy vegetables and broccoli, cooked or raw: for example, broccoli; spinach; romaine; kale; collard, turnip, and mustard greens.
- Red and orange vegetables: All fresh, frozen, and canned red and orange vegetables or juice, cooked or raw: for example, tomatoes, tomato juice, red peppers, carrots, sweet potatoes, winter squash, and pumpkin.
- Legumes (beans and peas): All cooked from dry or canned beans and peas: for example, kidney beans, white beans, black beans, lentils, chickpeas, pinto beans, split peas, and edamame (green soybeans). Does not include green beans or green peas.
- Starchy vegetables: All fresh, frozen, and canned starchy vegetables: for example, white potatoes, corn, green peas, green lima beans, plantains, and cassava.
- Other vegetables: All other fresh, frozen, and canned vegetables, cooked or raw: for example, iceberg lettuce, green beans, onions, cucumbers, cabbage, celery, zucchini, mushrooms, and green peppers.
- Fruits
- All fresh, frozen, canned, and dried fruits and fruit juices: for example, oranges and orange juice, apples and apple juice, bananas, grapes, melons, berries, and raisins.
- Grains
- Whole grains: All whole-grain products and whole grains used as ingredients: for example, whole-wheat bread, whole-grain cereals and crackers, oatmeal, quinoa, popcorn, and brown rice.
- Refined grains: All refined-grain products and refined grains used as ingredients: for example, white breads, refined grain cereals and crackers, pasta, and white rice. Refined grain choices should be enriched.
- Dairy
- All milk, including lactose-free and lactose-reduced products and fortified soy beverages (soymilk), yogurt, frozen yogurt, dairy desserts, and cheeses. Most choices should be fat-free or low-fat. Cream, sour cream, and cream cheese are not included due to their low calcium content.
- Protein Foods
- All seafood, meats, poultry, eggs, soy products, nuts, and seeds. Meats and poultry should be lean or low-fat and nuts should be unsalted. Legumes (beans and peas) can be considered part of this group as well as the vegetable group, but should be counted in one group only.
Evidence shows that healthy eating patterns are associated with positive health outcomes. And the evidence base for associations between eating patterns and specific health outcomes continues to grow. Strong evidence shows that healthy eating patterns are associated with a reduced risk of cardiovascular disease. Moderate evidence indicates that healthy eating patterns also are associated with a reduced risk of type 2 diabetes, certain types of cancers (such as colorectal and postmenopausal breast cancers), overweight, and obesity. Emerging evidence also suggests that relationships may exist between eating patterns and some neuro-cognitive disorders and congenital anomalies.
Within this body of evidence, higher intakes of vegetables and fruits consistently have been identified as characteristics of healthy eating patterns; whole grains have been identified as well, although with slightly less consistency. Other characteristics of healthy eating patterns have been identified with less consistency and include fat-free or low-fat dairy, seafood, legumes, and nuts.
Lower intakes of meats, including processed meats; processed poultry; sugar-sweetened foods, particularly beverages; and refined grains have often been identified as characteristics of healthy eating patterns.
A) Vegetables
Healthy intake: Healthy eating patterns include a variety of vegetables from all of the five vegetable subgroups—dark green, red and orange, legumes (beans and peas), starchy, and other. These include all fresh, frozen, canned, and dried options in cooked or raw forms, including vegetable juices. The recommended amount of vegetables in the Healthy U.S.-Style Eating Pattern at the 2,000-calorie level is 2½ cup-equivalents of vegetables per day. In addition, weekly amounts from each vegetable subgroup are recommended to ensure variety and meet nutrient needs.
Key nutrient contributions: Vegetables are important sources of many nutrients, including dietary fiber, potassium, vitamin A, vitamin C, vitamin K, copper, magnesium, vitamin E, vitamin B6, folate, iron, manganese, thiamin, niacin, and choline. Each of the vegetable subgroups contributes different combinations of nutrients, making it important for individuals to consume vegetables from all the subgroups. For example, dark-green vegetables provide the most vitamin K, red and orange vegetables the most vitamin A, legumes the most dietary fiber, and starchy vegetables the most potassium. Vegetables in the “other” vegetable subgroup provide a wide range of nutrients in varying amounts.
Considerations: To provide all of the nutrients and potential health benefits that vary across different types of vegetables, the Healthy U.S.-Style Eating Pattern includes weekly recommendations for each subgroup. Vegetable choices over time should vary and include many different vegetables. Vegetables should be consumed in a nutrient-dense form, with limited additions such as salt, butter, or creamy sauces. When selecting frozen or canned vegetables, choose those lower in sodium.
B) Fruits
Healthy intake: Healthy eating patterns include fruits, especially whole fruits. The fruits food group includes whole fruits and 100% fruit juice. Whole fruits include fresh, canned, frozen, and dried forms. The recommended amount of fruits in the Healthy U.S.-Style Eating Pattern at the 2,000-calorie level is 2 cup-equivalents per day. One cup of 100% fruit juice counts as 1 cup of fruit. Although fruit juice can be part of healthy eating patterns, it is lower than whole fruit in dietary fiber and when consumed in excess can contribute extra calories. Therefore, at least half of the recommended amount of fruits should come from whole fruits. When juices are consumed, they should be 100% juice, without added sugars. Also, when selecting canned fruit, choose options that are lowest in added sugars. One-half cup of dried fruit counts as one cup-equivalent of fruit. Similar to juice, when consumed in excess, dried fruits can contribute extra calories.
Key nutrient contributions: Among the many nutrients fruits provide are dietary fiber, potassium, and vitamin C.
Considerations: Juices may be partially fruit juice, and only the proportion that is 100% fruit juice counts (e.g., 1 cup of juice that is 50% juice counts as ½ cup of fruit juice). The remainder of the product may contain added sugars. Sweetened juice products with minimal juice content, such as juice drinks, are considered to be sugar-sweetened beverages rather than fruit juice because they are primarily composed of water with added sugars (see the Added Sugars section). The percent of juice in a beverage may be found on the package label, such as “contains 25% juice” or “100% fruit juice.” The amounts of fruit juice allowed in the US Department of Agriculture (USDA) Food Patterns for young children align with the recommendation from the American Academy of Pediatrics that young children consume no more than 4 to 6 fluid ounces of 100% fruit juice per day. Fruits with small amounts of added sugars can be accommodated in the diet as long as calories from added sugars do not exceed 10 percent per day and total calorie intake remains within limits.
C) Grains
Healthy Intake: Healthy eating patterns include whole grains and limit the intake of refined grains and products made with refined grains, especially those high in saturated fats, added sugars, and/or sodium, such as cookies, cakes, and some snack foods. The grains food group includes grains as single foods (e.g., rice, oatmeal, and popcorn), as well as products that include grains as an ingredient (e.g., breads, cereals, crackers, and pasta). Grains are either whole or refined. Whole grains (e.g., brown rice, quinoa, and oats) contain the entire kernel, including the endosperm, bran, and germ. Refined grains differ from whole grains in that the grains have been processed to remove the bran and germ, which removes dietary fiber, iron, and other nutrients. The recommended amount of grains in the Healthy U.S.-Style Eating Pattern at the 2,000-calorie level is 6 ounce-equivalents per day. At least half of this amount should be whole grains.
Key nutrient contributions: Whole grains are a source of nutrients, such as dietary fiber, iron, zinc, manganese, folate, magnesium, copper, thiamin, niacin, vitamin B6, phosphorus, selenium, riboflavin, and vitamin A. Whole grains vary in their dietary fiber content. Most refined grains are enriched, a process that adds back iron and four B vitamins (thiamin, riboflavin, niacin, and folic acid). Because of this process, the term “enriched grains” is often used to describe these refined grains.
Considerations: Individuals who eat refined grains should choose enriched grains. Those who consume all of their grains as whole grains should include some grains, such as some whole-grain ready-to-eat breakfast cereals, that have been fortified with folic acid. This is particularly important for women who are or are capable of becoming pregnant, as folic acid fortification in the United States has been successful in reducing the incidence of neural tube defects during fetal development. Although grain products that are high in added sugars and saturated fats, such as cookies, cakes, and some snack foods, should be limited, as discussed in the Added Sugars and Saturated Fats sections below, grains with some added sugars and saturated fats can fit within healthy eating patterns.
D) Dairy
Healthy intake: Healthy eating patterns include fat-free and low-fat (1%) dairy, including milk, yogurt, cheese, or fortified soy beverages (commonly known as “soymilk”). Soy beverages fortified with calcium, vitamin A, and vitamin D, are included as part of the dairy group because they are similar to milk based on nutrient composition and in their use in meals. Other products sold as “milks” but made from plants (e.g., almond, rice, coconut, and hemp “milks”) may contain calcium and be consumed as a source of calcium, but they are not included as part of the dairy group because their overall nutritional content is not similar to dairy milk and fortified soy beverages (soymilk). The recommended amounts of dairy in the Healthy U.S.-Style Pattern are based on age rather than calorie level and are 2 cup-equivalents per day for children ages 2 to 3 years, 2½ cup-equivalents per day for children ages 4 to 8 years, and 3 cup-equivalents per day for adolescents ages 9 to 18 years and for adults.
Key nutrient contributions: The dairy group contributes many nutrients, including calcium, phosphorus, vitamin A, vitamin D (in products fortified with vitamin D), riboflavin, vitamin B12, protein, potassium, zinc, choline, magnesium, and selenium.
Considerations: Fat-free and low-fat (1%) dairy products provide the same nutrients but less fat (and thus, fewer calories) than higher fat options, such as 2% and whole milk and regular cheese. Fat-free or low-fat milk and yogurt, in comparison to cheese, contain less saturated fats and sodium and more potassium, vitamin A, and vitamin D. Thus, increasing the proportion of dairy intake that is fat-free or low-fat milk or yogurt and decreasing the proportion that is cheese would decrease saturated fats and sodium and increase potassium, vitamin A, and vitamin D provided from the dairy group. Individuals who are lactose intolerant can choose low-lactose and lactose-free dairy products. Those who are unable or choose not to consume dairy products should consume foods that provide the range of nutrients generally obtained from dairy, including protein, calcium, potassium, magnesium, vitamin D, and vitamin A (e.g., fortified soy beverages [soymilk]). Additional sources of potassium, calcium, and vitamin D.
E) Protein Foods
Healthy intake: Healthy eating patterns include a variety of protein foods in nutrient-dense forms. The protein foods group comprises a broad group of foods from both animal and plant sources and includes several subgroups: seafood; meats, poultry, and eggs; and nuts, seeds, and soy products. Legumes (beans and peas) may also be considered part of the protein foods group as well as the vegetables group. Protein also is found in some foods from other food groups (e.g., dairy). The recommendation for protein foods in the Healthy U.S.-Style Eating Pattern at the 2,000-calorie level is 5½ ounce-equivalents of protein foods per day.
Key nutrient contributions: Protein foods are important sources of nutrients in addition to protein, including B vitamins (e.g., niacin, vitamin B12, vitamin B6, and riboflavin), selenium, choline, phosphorus, zinc, copper, vitamin D, and vitamin E). Nutrients provided by various types of protein foods differ. For example, meats provide the most zinc, while poultry provides the most niacin. Meats, poultry, and seafood provide heme iron, which is more bioavailable than the non-heme iron found in plant sources. Heme iron is especially important for young children and women who are capable of becoming pregnant or who are pregnant. Seafood provides the most vitamin B12 and vitamin D, in addition to almost all of the polyunsaturated omega-3 fatty acids, eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA), in the Patterns. Eggs provide the most choline, and nuts and seeds provide the most vitamin E. Soy products are a source of copper, manganese, and iron, as are legumes.
Considerations: For balance and flexibility within the food group, the Healthy U.S.-Style Eating Pattern includes weekly recommendations for the subgroups: seafood; meats, poultry, and eggs; and nuts, seeds, and soy products. A specific recommendation for at least 8 ounce-equivalents of seafood per week also is included for the 2,000-calorie level. One-half ounce of nuts or seeds counts as 1 ounce-equivalent of protein foods, and because they are high in calories, they should be eaten in small portions and used to replace other protein foods rather than being added to the diet. When selecting protein foods, nuts and seeds should be unsalted, and meats and poultry should be consumed in lean forms. Processed meats and processed poultry are sources of sodium and saturated fats, and intake of these products can be accommodated as long as sodium, saturated fats, added sugars, and total calories are within limits in the resulting eating pattern. The inclusion of protein foods from plants allows vegetarian options to be accommodated.
F) Oils
Healthy intake: Oils are fats that contain a high percentage of monounsaturated and polyunsaturated fats and are liquid at room temperature. Although they are not a food group, oils are emphasized as part of healthy eating patterns because they are the major source of essential fatty acids and vitamin E. Commonly consumed oils extracted from plants include canola, corn, olive, peanut, safflower, soybean, and sunflower oils. Oils also are naturally present in nuts, seeds, seafood, olives, and avocados. The fat in some tropical plants, such as coconut oil, palm kernel oil, and palm oil, are not included in the oils category because they do not resemble other oils in their composition. Specifically, they contain a higher percentage of saturated fats than other oils. The recommendation for oils in the Healthy U.S.-Style Eating Pattern at the 2,000-calorie level is 27 g (about 5 teaspoons) per day.
Key nutrient contributions: Oils provide essential fatty acids and vitamin E.
Considerations: Oils are part of healthy eating patterns, but because they are a concentrated source of calories, the amount consumed should be within the AMDR for total fats without exceeding calorie limits. Oils should replace solid fats rather than being added to the diet.
Foods to Limit
To keep weight in check at any age, you should avoid a lot of excess calories from added sugars, fat and alcohol.
- Limit regular soft drinks, sugar-sweetened beverages, candy, baked goods and fried foods.
- Limit alcohol intake to one drink per day. One drink is equal to 12 ounces of beer, 5 ounces of wine or 1.5 ounces of liquor.
- Opt for low-fat dairy and meat products instead of their full-fat counterparts.
Eat fewer foods that are high in saturated fat — the kind found in fatty meats, sausages, cheese and full-fat dairy products, baked goods and pizza.
Energy Foods
Since men have more muscle and are typically bigger than women, they require more calories throughout the day. Moderately active males should eat 2,000 to 2,800 calories per day. Your energy needs depend on your height, weight and activity level.
For energy, weight management and disease prevention, men should eat whole grains such as whole-grain bread, pasta, cereal, brown rice, oats, barley, fruits and vegetables. These foods are high in fiber, help manage hunger and fullness and help fend off certain cancers, such as prostate and colon.
Beyond Meat
Men are typically meat-eaters because of the perception that more protein equals more muscle mass. That is not the case unless exercise is involved. Men tend to view red meat as more masculine than other proteins; often this leads them to “order the steak.” It’s not the steak that’s unhealthy, it’s skipping the whole grains and vegetables. In addition, excessive meat eating is linked to heart disease and colorectal cancer in men.
Eat red meat less frequently, and, instead, focus on more fruits, vegetables and low-fat dairy products. This will not only help you keep weight off, but it can help keep blood pressure down. Cut down on saturated fat from meat, cheese and fried foods. Instead, opt for foods with unsaturated, heart-healthy fats such as olive oil, canola oil, nuts, seeds and avocadoes.
Weight and Disease Risk
More than women, men gain weight around the middle; that’s due to the male hormone testosterone. If your waist measures more than 40 inches around, it’s time to shed some pounds. This fat around the waist is typically buried deep in the abdomen and increases your risk for diabetes, heart disease and dementia.
Alcohol
If your hormones imbalance is under control and you do not have high blood pressure, your doctor may allow you to drink alcohol in moderation. Keep in mind that if you drink alcohol while taking insulin or other diabetes medication, your risk of having low blood sugar may increase.
If you drink alcohol, limit yourself to one drink a day if you are a woman and two drinks a day if you are a man. Avoid sugary mixed drinks. Never drink alcohol on an empty stomach.
Smoking
Smoking greatly increases your risk of heart disease, eye disease, and blood vessel disease, which are major complications of diabetes. Stopping smoking is the single best thing you can do to lower your chances of developing heart and blood vessel disease.
Exercise For Overall Health
Exercise is an important part of your health. Regular daily exercise helps with weight control, muscle strength and stress management. The American Heart Association 3 recommends the following amounts of physical activity to maintain cardiovascular health:
- At least 30 minutes of moderate-intensity aerobic activity at least 5 days per week for a total of 150 minutes.
OR
- At least 25 minutes of vigorous aerobic activity at least 3 days per week for a total of 75 minutes; or a combination of moderate- and vigorous-intensity aerobic activity.
AND
- Moderate- to high-intensity muscle-strengthening activity at least 2 days per week for additional health benefits.
For Lowering Blood Pressure and Cholesterol
- An average 40 minutes of moderate- to vigorous-intensity aerobic activity 3 or 4 times per week.
Add these activities to your weekly fitness routine to slow down your body’s clock.
- Endurance exercises. Activities such as running, cycling and swimming are the best ways to improve your cardiovascular function and prevent your metabolism from slowing down. Aim to get at least 30 to 60 minutes of moderate-intensity cardio (aerobic) activity most days, for a total of 150 minutes each week.
- Interval training. Instead of a steady-state bout of running or cycling, with high-intensity interval training, you alternate bursts of intense activity (that makes you breathe heavily) with lighter activity. An example workout would include five intervals at a higher intensity (which may mean increasing speed, incline or resistance) for one to two minutes with a one- to two-minute period in between at a slightly lower intensity. An easy way to determine if you’re working hard enough is whether you can talk (or sing) easily. If you can’t, you’re working hard enough during your intervals. Add interval training to your workout routine one or two days each week.
- Strength training. Maintaining muscle mass is very important as you age, since both men and women lose muscle mass as they age and replace it with fat. Skeletal muscle burns more calories at rest compared to fat tissue. It also protects your joints and can help your bones become stronger and maintain their density, which can prevent fractures. Maintaining and increasing muscle mass can also help improve balance and agility, which is crucial as you get older.
Exercise and Physical Activity
Your doctor may have good ideas about types of exercise that would be best for you. Exercise is important for people with hormones imbalance because it:
- Helps insulin work better to lower blood sugar
- Helps keep weight down
- Is good for the heart, blood vessels, and lungs
- Gives you more energy
If you have heart disease or risk factors for heart disease, such as high cholesterol, high blood pressure, or poor diabetes control, check with your doctor about whether or not you need a stress test before beginning an exercise program.
If you have nerve damage to your feet, be careful to wear well-fitting shoes and socks to avoid blisters. Talk with your physician and/or podiatrist about your exercise program.
Why is Sleep Important ?
Sleep plays a vital role in good health and well-being throughout your life. Getting enough quality sleep at the right times can help protect your mental health, physical health, quality of life, and safety 4.
The way you feel while you’re awake depends in part on what happens while you’re sleeping 4. During sleep, your body is working to support healthy brain function and maintain your physical health. In children and teens, sleep also helps support growth and development.
The damage from sleep deficiency can occur in an instant (such as a car crash), or it can harm you over time. For example, ongoing sleep deficiency can raise your risk for some chronic health problems. It also can affect how well you think, react, work, learn, and get along with others.
Healthy Brain Function and Emotional Well-Being
Sleep helps your brain work properly. While you’re sleeping, your brain is preparing for the next day. It’s forming new pathways to help you learn and remember information.
Studies show that a good night’s sleep improves learning 4. Whether you’re learning math, how to play the piano, how to perfect your golf swing, or how to drive a car, sleep helps enhance your learning and problem-solving skills. Sleep also helps you pay attention, make decisions, and be creative.
Studies also show that sleep deficiency alters activity in some parts of the brain. If you’re sleep deficient, you may have trouble making decisions, solving problems, controlling your emotions and behavior, and coping with change. Sleep deficiency also has been linked to depression, suicide, and risk-taking behavior 4.
Children and teens who are sleep deficient may have problems getting along with others. They may feel angry and impulsive, have mood swings, feel sad or depressed, or lack motivation. They also may have problems paying attention, and they may get lower grades and feel stressed 4.
Physical Health
Sleep plays an important role in your physical health. For example, sleep is involved in healing and repair of your heart and blood vessels. Ongoing sleep deficiency is linked to an increased risk of heart disease, kidney disease, high blood pressure, diabetes, and stroke 4.
A lack of sleep also puts your body under stress and may trigger the release of more adrenaline, cortisol, and other stress hormones during the day. These hormones keep your blood pressure from dipping during sleep, which increases your risk for heart disease. Lack of sleep also may trigger your body to produce more of certain proteins thought to play a role in heart disease. For example, some studies find that people who repeatedly don’t get enough sleep have higher than normal blood levels of C-reactive protein, a sign of inflammation. High levels of this protein may indicate an increased risk for a condition called atherosclerosis, or hardening of the arteries.
Sleep deficiency also increases the risk of obesity. For example, one study of teenagers showed that with each hour of sleep lost, the odds of becoming obese went up. Sleep deficiency increases the risk of obesity in other age groups as well 4.
Sleep helps maintain a healthy balance of the hormones that make you feel hungry (ghrelin) or full (leptin) 4. When you don’t get enough sleep, your level of ghrelin goes up and your level of leptin goes down. This makes you feel hungrier than when you’re well-rested 4.
Evidence is growing that sleep is a powerful regulator of appetite, energy use, and weight control. During sleep, the body’s production of the appetite suppressor leptin increases and the appetite stimulant grehlin decreases. Studies find that the less people sleep, the more likely they are to be overweight or obese and prefer eating foods that are higher in calories and carbohydrates. People who report an average total sleep time of 5 hours a night, for example, are much more likely to become obese, compared with people who sleep 7–8 hours a night.
Sleep also affects how your body reacts to insulin, the hormone that controls your blood glucose (sugar) level. Sleep deficiency results in a higher than normal blood sugar level, which may increase your risk for diabetes 4. One study found that, when healthy young men slept only 4 hours a night for 6 nights in a row, their insulin and blood sugar levels matched those seen in people who were developing diabetes. Another study found that women who slept less than 7 hours a night were more likely to develop diabetes over time than those who slept between 7 and 8 hours a night.
Sleep also supports healthy growth and development 4. Deep sleep triggers the body to release the hormone that promotes normal growth in children and teens. This hormone also boosts muscle mass and helps repair cells and tissues in children, teens, and adults. Sleep also plays a role in puberty and fertility.
Your immune system relies on sleep to stay healthy 4. This system defends your body against foreign or harmful substances. Ongoing sleep deficiency can change the way in which your immune system responds. For example, if you’re sleep deficient, you may have trouble fighting common infections.
During sleep, your body creates more cytokines—cellular hormones that help the immune system fight various infections. Lack of sleep can reduce your body’s ability to fight off common infections. Research also reveals that a lack of sleep can reduce the body’s response to the flu vaccine. For example, sleep-deprived volunteers given the flu vaccine produced less than half as many flu antibodies as those who were well rested and given the same vaccine.
How Much Sleep Do You Need ?
The amount of sleep you need each day will change over the course of your life, your sleep patterns change as you age. Despite variations in sleep quantity and quality, both related to age and between individuals, studies suggest that the optimal amount of sleep needed to perform adequately, avoid a sleep debt, and not have problem sleepiness during the day is about 7–8 hours for adults and at least 10 hours for school-aged children and adolescents. Similar amounts seem to be necessary to avoid an increased risk of developing obesity, diabetes, or cardiovascular diseases.
Quality of sleep and the timing of sleep are as important as quantity. People whose sleep is frequently interrupted or cut short may not get enough of both non-REM sleep and REM sleep. Both types of sleep appear to be crucial for learning and memory—and perhaps for the restorative benefits of healthy sleep, including the growth and repair of cells.
The table below shows general recommendations for different age groups. This table reflects recent American Academy of Sleep Medicine recommendations that the American Academy of Pediatrics has endorsed.
Table 2. Recommended Amount of Sleep
Age | Recommended Amount of Sleep |
---|---|
Infants aged 4-12 months | 12-16 hours a day (including naps) |
Children aged 1-2 years | 11-14 hours a day (including naps) |
Children aged 3-5 years | 10-13 hours a day (including naps) |
Children aged 6-12 years | 9-12 hours a day |
Teens aged 13-18 years | 8-10 hours a day |
Adults aged 18 years or older | 7–8 hours a day |
Babies initially sleep as much as 16 to 18 hours per day, which may boost growth and development (especially of the brain). School-age children and teens on average need about 9.5 hours of sleep per night. Most adults need 7-9 hours of sleep a night, but after age 60, nighttime sleep tends to be shorter, lighter, and interrupted by multiple awakenings. Elderly people are also more likely to take medications that interfere with sleep.
For example, some older people complain of difficulty falling asleep, early morning awakenings, frequent and long awakenings during the night, daytime sleepiness, and a lack of refreshing sleep. Many sleep problems, however, are not a natural part of sleep in the elderly. Their sleep complaints may be due, in part, to medical conditions, illnesses, or medications they are taking—all of which can disrupt sleep. In fact, one study found that the prevalence of sleep problems is very low in healthy older adults. Other causes of some of older adults’ sleep complaints are sleep apnea, restless legs syndrome, and other sleep disorders that become more common with age. Also, older people are more likely to have their sleep disrupted by the need to urinate during the night.
There is no evidence that indicates older people can get by with less sleep than younger people. There is some evidence showing that the biological clock shifts in older people, so they are more apt to go to sleep earlier at night and wake up earlier in the morning. Poor sleep in older people may result in excessive daytime sleepiness, attention and memory problems, depressed mood, and overuse of sleeping pills.
Across the lifespan, the sleep period tends to advance, namely relative to teenagers; older adults tend to go to bed earlier and wake earlier. The quality—but not necessarily the quantity—of deep, NREM sleep also changes, with a trend toward lighter sleep. The relative percentages of stages of sleep appear to stay mostly constant after infancy. From midlife through late life, people awaken more throughout the night. These sleep disruptions cause older people to lose more and more of stages 1 and 2 non-REM sleep as well as REM sleep.
In general, people are getting less sleep than they need due to longer work hours and the availability of round-the-clock entertainment and other activities 5.
If you routinely lose sleep or choose to sleep less than needed, the sleep loss adds up. The total sleep lost is called your sleep debt. For example, if you lose 2 hours of sleep each night, you’ll have a sleep debt of 14 hours after a week. Many people feel they can “catch up” on missed sleep during the weekend but, depending on how sleep-deprived they are, sleeping longer on the weekends may not be adequate 5.
Some people nap as a way to deal with sleepiness. Naps may provide a short-term boost in alertness and performance. However, napping doesn’t provide all of the other benefits of night-time sleep. Thus, you can’t really make up for lost sleep.
Some people sleep more on their days off than on work days. They also may go to bed later and get up later on days off.
Sleeping more on days off might be a sign that you aren’t getting enough sleep. Although extra sleep on days off might help you feel better, it can upset your body’s sleep–wake rhythm.
Bad sleep habits and long-term sleep loss will affect your health. If you’re worried about whether you’re getting enough sleep, try using a sleep diary for a couple of weeks.
Sleeping when your body is ready to sleep also is very important. Sleep deficiency can affect people even when they sleep the total number of hours recommended for their age group.
For example, people whose sleep is out of sync with their body clocks (such as shift workers) or routinely interrupted (such as caregivers or emergency responders) might need to pay special attention to their sleep needs.
If your job or daily routine limits your ability to get enough sleep or sleep at the right times, talk with your doctor. You also should talk with your doctor if you sleep more than 8 hours a night, but don’t feel well rested. You may have a sleep disorder or other health problem.
How to get better sleep at night
You can take steps to improve your sleep habits. First, make sure that you allow yourself enough time to sleep. With enough sleep each night, you may find that you’re happier and more productive during the day.
Sleep often is the first thing that busy people squeeze out of their schedules. Making time to sleep will help you protect your health and well-being now and in the future.
Getting enough sleep is good for your health. Here are a few tips to improve your sleep:
- Set a schedule. Go to bed and wake up at the same time every day. For children, have a set bedtime and a bedtime routine. Don’t use the child’s bedroom for timeouts or punishment.
- Try to keep the same sleep schedule on weeknights and weekends. Limit the difference to no more than about an hour. Staying up late and sleeping in late on weekends can disrupt your body clock’s sleep–wake rhythm.
- Use the hour before bed for quiet time. Avoid strenuous exercise and bright artificial light, such as from a TV or computer screen. The light may signal the brain that it’s time to be awake.
- Create a room for sleep – avoid bright lights and loud sounds, keep the room at a comfortable temperature, and don’t watch TV or have a computer in your bedroom.
- Avoid nicotine (for example, cigarettes) and caffeine (including caffeinated soda, coffee, tea, and chocolate). Nicotine and caffeine are stimulants, and both substances can interfere with sleep. The effects of caffeine can last as long as 8 hours. So, a cup of coffee in the late afternoon can make it hard for you to fall asleep at night.
- Avoid heavy and/or large meals within a couple hours of bedtime. (Having a light snack is okay.) Also, avoid alcoholic drinks before bed.
- Exercise 20 to 30 minutes a day but no later than a few hours before going to bed.
- Relax before bed – try a warm bath, reading, or another relaxing routine.
- Don’t lie in bed awake. If you can’t get to sleep, do something else, like reading or listening to music, until you feel tired.
- Spend time outside every day (when possible) and be physically active.
- Keep your bedroom quiet, cool, and dark (a dim night light is fine, if needed).
Napping during the day may provide a boost in alertness and performance. However, if you have trouble falling asleep at night, limit naps or take them earlier in the afternoon. Adults should nap for no more than 20 minutes.
Napping in preschool-aged children is normal and promotes healthy growth and development.
See a doctor if you have a problem sleeping or if you feel unusually tired during the day. Most sleep disorders can be treated effectively.
How to Sleep Better if You Are a Shift Worker
Some people have schedules that conflict with their internal body clocks. For example, shift workers and teens who have early school schedules may have trouble getting enough sleep. This can affect how they feel mentally, physically, and emotionally.
If you’re a shift worker, you may find it helpful to:
- Increase your total amount of sleep by adding naps and lengthening the amount of time you allot for sleep.
- Keep the lights bright at work
- Minimize the number of shift changes so that your body’s biological clock has a longer time to adjust to a nighttime work schedule.
- Limit caffeine use to the first part of your shift to promote alertness at night.
- Remove sound and light distractions in your bedroom during daytime sleep (for example, use light-blocking curtains)
If you’re still not able to fall asleep during the day or have problems adapting to a shift-work schedule, talk with your doctor about other options to help you sleep.
When possible, employers and schools might find it helpful to consider options to address issues related to sleep deficiency.
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- Why Is Sleep Important ? National Heart, Lung and Blood Institute. https://www.nhlbi.nih.gov/health/health-topics/topics/sdd/why[↩][↩][↩][↩][↩][↩][↩][↩][↩][↩][↩][↩][↩]
- Brain Basics: Understanding Sleep. National Institute of Neurological Disorders and Stroke. https://www.ninds.nih.gov/Disorders/Patient-Caregiver-Education/Understanding-Sleep[↩][↩]