What is buckwheat ?

What is Buckwheat ?

Common buckwheat (Fagopyrum esculentum) is a pseudo-cereal crop that produces short, wide-spreading plants bearing bright green, heart-shaped leaves and small white flowers ¹.

Buckwheat technically speaking is not classified as a ‘true’ grain, but rather a ‘pseudo-cereal’. However due to its nutritional profile, nutty flavour, appearance and culinary applications have led it to be commonly referred to as a grain ². It is neither a grain or a relative of wheat, but rather, its seeds so closely resemble the much larger seeds of the beech tree that the plant has been called “beech wheat,” or buckwheat, ever since ². Buckwheat has played an important role in diets around the world, mainly in Asia and Eastern Europe for around 8,000 years.

As a grain, buckwheat more than makes up for its less-than-striking appearance as a plant. Buckwheat groats are shaped almost like a pyramid, or a triangle with a rounded bottom and gently tapered sides. This unusual seed shape is actually how buckwheat got its common name ¹.

Buckwheat has a gene that lets it make red or green immature fruit, but the hull of common buckwheat becomes dark brown or almost black as the seeds reach maturity and are ready to harvest ¹.

As a short-season crop that performs well in acidic and under-fertilized soil, buckwheat can perform as a “smother” crop, used to keep weeds at bay, and to keep soil erosion to a minimum while fields “rest” during crop rotation ¹. It performs best when sown in June, and because it blooms for quite a while (even into September), its nectar provides for late-season honey that can be dark amber in color and rich in flavor. Once the flowers have yielded buckwheat groats and it’s time to harvest, the plant stalks can be dried further and used as straw for livestock, or the entire plants can be tilled under to help next year’s soil retain more moisture ¹.

Tartary Buckwheat

Another type of buckwheat is Tartary buckwheat (Fagopyrum tataricum) also known as duckwheat, India buckwheat, India wheat, green buckwheat, ku qiao or bitter buckwheat. Tartary buckwheat was domesticated in east Asia, and is also cultivated in Europe and North America. While it is an unfamiliar food in the West, it is common in the Himalayan region today, as well as other regions in Southwest China such as Guizhou province.

Tartary buckwheat (Fagopyrum tataricum) contains approximately 100-fold higher amounts of rutin in its seeds compared to common buckwheat ³, ⁴. Tartary buckwheat contains a range of nutrients including bioactive carbohydrates and proteins, polyphenols, phytosterols, vitamins, carotenoids, and minerals. Compared with the more widely cultivated and utilised cousin the common buckwheat (F. esculentum), tartary buckwheat tends to contain higher amounts of certain bioactive components such as rutin, which contributes to tartary buckwheat’s various health benefits such as anti-oxidative, anti-cancer, anti-hypertension, anti-diabetic, cholesterol-lowering, and cognition-improving ⁵.

Rutin is a flavonoid of the flavonol type, which is commonly found in plants ⁶. Rutin shows antioxidant effects via scavenging of radiation-induced free radicals ⁷. In addition, it has several pharmacological functions such as anti-inflammatory, anti-diabetic, and blood capillary strengthening properties ⁸. Kamalakkannan and Prince ⁹ reported that oral administration of rutin decreased blood glucose levels and increased insulin secretion in streptozotocin-induced diabetic rats. Other reports suggested that oral administration of rutin significantly decreased the levels of lipids in plasma and tissues in streptozotocin-induced diabetic rats ¹⁰. In addition, rutin has cardioprotective effects ¹¹, which are related to its ability to inhibit platelet aggregation ¹². Although it has been reported that rutin has several pharmacological effects, its exact mechanism and metabolism were not fully elucidated.

Is Buckwheat Gluten Free ?

Yes. Buckwheat is a naturally gluten-free whole grain ¹, ¹³.

Buckwheat Nutrition Value

Buckwheat provides a very high level of protein, second highest only to oats. Not only is buckwheat protein well-balanced and rich in lysine, its amino acid score is 100, which is one of the highest amino acid scores among plant sources as well ¹. It’s important to note there is some evidence that buckwheat protein digestibility in humans can be somewhat low ¹. While this makes it a less than ideal source of protein for growing children or anyone with digestive tract issues, it’s perfectly fine for the grown-ups of the world. Besides, humans are meant to have a varied, omnivorous diet, so it’s good to obtain protein from a variety of sources.

Nutrition values of buckwheat:

• Gluten free.
• Buckwheat contains higher levels of zinc, copper, potassium, manganese and magnesium than other cereal grains, and the bioavailability of zinc, copper, and potassium from buckwheat is also quite high.
• High in protein (13-15%), second highest only to oats, and rich in the amino acid lysine.
• Rich in carbohydrates (mainly starch).
• Rich in polyunsaturated essential fatty acids, such as linoleic acid.
• Contains vitamins B1, C and E.
• High in soluble fibre.
• Provides a potential source of resistant starch, as certain treatments of buckwheat starch or foods containing buckwheat increase the amount of retrograded, non-digestible starch.
• A rich source of polyphenol compounds.
• Contains rutin, a bioflavonoid thought to help control blood pressure and possess anti-inflammatory and anti-carcinogenic properties.

Table 1. Buckwheat Nutrition Content

[Source: United States Department of Agriculture, Agriculture Research Service. USDA Food Composition Databases. ¹⁴]

Table 2. Buckwheat Groats (Roasted Dry) Nutrition Content

[Source: United States Department of Agriculture, Agriculture Research Service. USDA Food Composition Databases. ¹⁴]

Table 3. Buckwheat Flour Nutrition Content

[Source: United States Department of Agriculture, Agriculture Research Service. USDA Food Composition Databases. ¹⁴]

Buckwheat Health Benefits

Buckwheat play two important roles for most adults:

• It’s high in soluble fiber, helping to slow down the rate of glucose absorption. This can be especially important in people with diabetes and anyone else trying to maintain balanced blood sugar levels. One Slovenian study in 2001 showed boiled buckwheat groats or bread made with at least 50% buckwheat flour induce much lower postprandial (after-meal) blood glucose and insulin responses than white wheat bread.

• It’s a potential source of resistant starch, a type of starch that escapes digestion in the small intestine. Resistant starch is often considered the third type of dietary fiber because it possesses some of the benefits of insoluble fiber and some of the benefits of soluble fiber. While most of the starch in buckwheat is readily digestible, the small portion that is resistant (about 4-7%) can be highly advantageous to overall colon health.

Buckwheat potassium helps your body to maintain the water and acid balance in blood and tissue cells, whilst its zinc helps to bolster your immune system. The copper in buckwheat may help prevent copper deficiency that can lead to a number of neurodegenerative diseases and disorders. Having buckwheat in your diet can help you stay fit, nimble, and healthy.

Buckwheat is also a good source of antioxidants, biologically high-valued amino acids ¹⁵, ¹⁶, dietary fiber ¹⁷, and minerals such as zinc, copper and manganese ¹⁸.

 

In Shanxi province, China, both common (Fagopyrum esculentum) and tartary (Fagopyrum tataricum) buckwheats are used to improve the health of patients with diabetes and cardiovascular diseases ¹⁹. A previous experimental buckwheat study concluded that intake of common buckwheat leaf tea could prevent further development of leg edema ²⁰, and a study by He et al. ²¹ showed a cholesterol-lowering effect of buckwheat. However, there are very few studies on the health effects of buckwheat, especially buckwheat products in humans.

• Eating Tartary Buckwheat may reduce body weight (cause weight loss)
  

In this study involving 149 subjects (42 males and 107 females aged 30–69 years) who had their body weight, body mass index (BMI), and body fat percentage  measured, at weeks 0 (baseline), 4, 8, and 12 after the start of rutin ingestion, and 3 weeks after the end of rutin ingestion ²². The active test foods were: rutin-rich tartary buckwheat food contains ‘Manten-Kirari’ buckwheat flour 50%, wheat flour 47%, wheat albumin 3% and the placebo food (wheat flour 97% and wheat albumin 3%). The results of that study showed subjects who were eating rutin-rich tartary buckwheat have significantly lower body weight and BMI than those in the placebo group at week 8. The body fat percentage in the subjects who were eating rutin-rich tartary buckwheat group at week 4 was lower than that in the placebo group. The researchers concluded that consuming rutin-rich Tartary buckwheat may be effective for body weight due to its antioxidant properties ²².

• Eating Buckwheat Products Produces Lower GI Response

In a joint effort to determine the characteristics of buckwheat starch and its potential for a reduced metabolic response after meals, researchers from Slovenia and Sweden scored human test subject’s responses to an assortment of buckwheat products, including boiled buckwheat groats, breads baked with 30-70% buckwheat flour, and bread baked from buckwheat groats. The highest level of resistant starch was found in the boiled buckwheat groats, while the resistant starch levels in the buckwheat breads were significantly lower, depending on whether flour or grouts had been used. The conclusion: All buckwheat products scored significantly lower on the after-meal blood glucose tests, while also scoring higher in satiety, than the control group’s white wheat bread ²³.

• Buckwheat Enhanced Gluten-free Bread a Healthier Gluten-free Alternative

Researches from the Polish Academy of Sciences recently published a study suggesting substituting some or all of the corn starch in many traditional gluten-free bread recipes with buckwheat flour. In addition to providing higher levels of antioxidants, B vitamins, magnesium, phosphorus and potassium, the study indicated that swapping 40% of the corn starch for buckwheat flour also increased its “overall sensory quality” when compared to the gluten-free bread used in the control. Although recipes were tested with anywhere from 10-40% buckwheat flour, the conclusion clearly points to the 40% buckwheat flour results as having the most nutritional benefits for Celiac sufferers ²⁴.

• Buckwheat Starch is A Good Energy Source

In a study found via the China National Knowledge Infrastructure, researchers at the Graduate University of the Chinese Academy of Sciences explored the digestibility of starch derived from oats, wheat, buckwheat, and sweet potatoes. The goal of this study was to determine which of the four starch sources might prove useful in high-energy diets. Pigs were fed diets containing vitamins, minerals, and starch from one of the four sources, and after 15 days, it was determined that buckwheat, along with oats and wheat, provided a better source of dietary energy than sweet potatoes ²⁵.

• Buckwheat Protein Shows Promise For Lowering Blood Glucose

A study from the Jilin Agricultural University in China investigated the blood glucose lowering potential of buckwheat protein, pitting it against a toxic glucose analogue called alloxan. This insidious chemical selectively destroys insulin-producing cells in the pancreas, causing characteristics similar to type 1 diabetes when found in rodents and many other animal species. Different doses of buckwheat protein were administered, and researchers discovered that the blood glucose levels of test subjects were indeed lowered when compared to the control group ²⁶.

• Germinated Buckwheat Extract Decreases Blood Pressure

A team of Korean researchers extracted the bioflavonoid rutin, thought to have blood-pressure lowering properties, from both raw buckwheat and germinated buckwheat. The team then studied the effects of both extracts on body weight and systolic blood pressure in rats. They also searched for any indication of the formation of peroxynitrite, an oxidant and nitrating agent that can damage a wide array of molecules in cells, including DNA and proteins. After five weeks, the systolic blood pressure of the rats treated with germinated buckwheat was lower than the group treated with raw buckwheat, but both groups showed significantly reduced oxidative damage in aortic cells when compared to the control group ²⁷.

• Buckwheat Provides Prebiotic-like Benefits And Can Be Considered a Healthy Food

In 2003, a study out of Madrid, Spain examined the high nutrient levels in buckwheat to determine whether it could behave as a prebiotic and be considered a healthy food. Prebiotics, of course, are indigestible food ingredients that stimulate the helpful bacteria in our digestive systems. Not only did the buckwheat-fed group emerge with a lower bodyweight when compared to the control, some of the best types of helpful bacteria were found, along with a decrease in some types of pathogenic bacteria ²⁸.

• Buckwheat Protein may have Cholesterol lowering activity
  

In a small animal experiment, 45 male hamsters were divided into five groups fed either the control diet or one of the four experimental diets containing 24% Tartary buckwheat protein, 24% rice protein, 24% wheat protein, or 5 g/kg of cholestyramine (cholestrol lowering medicine), respectively. Tartary buckwheat protein reduced plasma total cholesterol more effectively than cholestyramine (45% versus 37%), while rice and wheat proteins only reduced plasma total cholesterol by 10–13% ²⁹. In another experiment involving lab rats and mice, the consumption of tartary buckwheat protein product and common buckwheat protein product, both of which contain a compound quercetin, showed a mice and rats had reduction in total cholesterol which was associated with enhanced excretion of fecal fats ³⁰. In experiment number 2, the consumption of tartary buckwheat protein product and common buckwheat protein product for 27 day caused 62% and 43% reductions in the lithogenic index (gallstone forming) in mice fed cholesterol, respectively. The reduction in lithogenic index was associated with enhanced excretion of fecal bile acids ³¹. Taken together, these results suggest a potential source of tartary buckwheat protein as a functional food ingredient as well as common buckwheat protein.

In a small human study to find out if eating buckwheat could lower cholesterol, 62 female day-care centre staffs in Japan were fed either common buckwheat cookies or tartary buckwheat cookies for a total of weeks ³². At the end of two weeks, the type of buckwheat cookies were switched, so the group receiving common buckwheat are now eating tartary buckwheat and vice versa. When grouping the two types of buckwheat cookies together, there was a reduction of total serum cholesterol and HDL cholesterol, suggesting intake of buckwheat cookies may lower cholesterol levels ³².

How To Cook Buckwheat

Main culinary uses of buckwheat:

• Buckwheat flour – may be used to make gluten free crepes and pancakes. Up to half the rice, bean, sorghum or soy flour in gluten-free recipes may be used to make muffins, rolls, bread and cookies. Buckwheat flour also works well as a thickener for sauces, soups and casseroles.

• Buckwheat groats – are dehulled buckwheat kernels. The groats are used in many dishes throughout the world. In Asia they are consumed as noodles, dumplings and as unleavened chapattis, whereas in Europe, Kasha (toasted buckwheat groats) is used in dishes ranging from pilafs to mixtures with meat. In the US and Australia, the main use has been in pancakes, although, buckwheat is increasingly being eaten in the form of noodles, various ethnic dishes and gluten free foods.

• Soba noodles – buckwheat flour is mixed with wheat flour to produce Japanese noodles called ‘soba noodles’. The buckwheat flour content ranges from 50% to 80% depending on the type of noodle produced.

For more information on buckwheat recipes you may want to try out the Whole Grains Council recipes section here:

• Kasha and Beet Salad with Celery and Feta ³³,
• Kasha Varnishkes ³⁴,
• Buckwheat Pumpkin Muffins with Molasses-Cinnamon Glaze ³⁵,
• Buckwheat Mushroom Kreplach in Dill Tomato Sauce ³⁶.

Buckwheat Safety

Although eating buckwheat containing products is considered safe, there have been a very small and rarely reported cases of an allergic reaction to buckwheat. In this first reported case, there was an allergic rhinitis and asthma caused by sleeping on pillow filed with buckwheat ³⁷. Another buckwheat allergy cases were reported in the UK, one involving a 57-year-old man presented with anaphylaxis after eating home-baked bread prepared using buckwheat flour bought in France. In the second case, a 63-year-old lady presented with bronchospasm (narrowing of the airways) and urticaria (a round itchy skin rash) after consuming health-food muesli. Sensitisation was confirmed in both cases by positive skin prick testing and specific IgE to buckwheat ³⁸.

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