Buckwheat

A Complete Protein

Buckwheat is a gluten-free grain substitute, which is a source of complete protein. It delivers an abundance of tannins, catechins, the essential fatty acid alpha-linolenic acid, vitamins, minerals, and both soluble and insoluble fiber.

Two of its most important nutrients include D-chiro-inositol and rutin. Buckwheat is the greatest natural source of D-chiro-inositol,¹ a compound that reduces glucose levels and can be used as a treatment for diabetes.^2,3 The flavonoid rutin is known for its anti-inflammatory and platelet aggregation-inhibiting effects.⁴

Accumulating evidence demonstrates that buckwheat can be beneficial for managing diabetes,^2,3,5 cardiovascular disease,^5,6 arthritis,⁷ allergies,⁸ and obesity.⁵

A Unique Nutrient Profile

Despite its name, buckwheat is not a type of wheat nor even a type of grain. Instead, it is a seed related to rhubarb and sorrel that is often used as a grain substitute. But buckwheat’s unique nutrient profile makes it a step above grains. Grains such as wheat, maize, and rice do not provide the human body with the proportionate balance of amino acids required to produce complete protein because of an insufficient supply of the amino acid lysine.⁴

Buckwheat, on the other hand, contains all eight essential amino acids in excellent proportions—including a good supply of lysine. Because of that, buckwheat is a surprisingly rich source of protein. In fact, just one cup of buckwheat delivers 23 grams of high-quality protein.⁹ And unlike certain grass grains, buckwheat is gluten-free.¹⁰

Buckwheat’s most potent health effects may come from its rich supply of phytonutrients. Buckwheat contains high concentrations of D-chiro-inositol, a potent chemical variant of the B vitamin inositol that promotes healthy glucose levels.¹¹ Buckwheat also contains catechins and tannins, and it is especially rich in rutin and quercetin,¹² two nutrients known to fight free radicals and inflammation.

The abundant supply of vitamins and minerals in buckwheat includes riboflavin (vitamin B2), niacin (vitamin B3), phosphorus, zinc, iron, calcium, potassium, and selenium. Buckwheat also contains copious amounts of copper, magnesium, and manganese.⁹ Each of these minerals plays an important role in the body. Copper is required for red blood cell production. Magnesium relaxes blood vessels, lowers blood pressure, and serves as a cofactor for more than 300 enzymes, including those involved in the body’s use of glucose and insulin secretion.¹² Manganese supports bone and skin health, as well as critical biochemical processes.¹³

One cup of buckwheat delivers 68% of the recommended daily fiber intake (for a 2,000-calorie-a-day diet),⁹ substantially inhibiting the rate of glucose absorption, which is important for maintaining balanced blood sugar levels.¹⁴ In fact, the fiber content provided by buckwheat represents over 300% of the amount of fiber found in an equivalent serving of quinoa^9,15—which itself significantly exceeds whole wheat and rice in fiber content.¹⁶

Fiber delivers many additional health benefits beyond glucose control. It promotes healthy weight, normalizes bowel movements, lowers the risk of hemorrhoids and diverticular disease, decreases serum LDL cholesterol levels, and helps reduce blood pressure and inflammation. Limited evidence suggests that fiber may help prevent colorectal cancer (likely by binding and promoting the excretion of toxins from the gut).¹⁷

Buckwheat also provides a type of starch called resistant starch that is not digested in the small intestine. This is often classified as a third type of dietary fiber because it possesses some of the benefits of both soluble and insoluble fiber. Although only a small percentage of buckwheat starch is resistant to digestion, its activity may promote overall colon health.¹⁴

Superior Cardiovascular Benefits

Buckwheat contains a number of nutrients that deliver powerful cardiovascular benefits, including protection against blood clots, reducing blood pressure, and lowering cholesterol levels.

One important reason for these benefits is that buckwheat is one of the richest food sources of the flavonoid rutin,¹⁸ a nutrient that is well known for its ties to heart health.

Scientists have found that rutin prevents blood clots from forming, making it a promising therapy for patients at risk for strokes and heart attacks.¹⁹

In fact, when Harvard researchers tested 4,900 compounds, they discovered that rutin was, by far, the most potent anticlotting compound of the group. It works by blocking a potentially dangerous enzyme called protein disulfide isomerase (PDI) that is rapidly excreted from both endothelial cells and platelets when a clot forms in an artery or vein. The researchers are hopeful that future research on rutin will lead to an effective but simple therapy for those at risk of a clotting-related event.¹⁹

Rutin has also been shown to help reduce blood pressure. According to one study, people taking rutin had a 36% reduction in blood pressure.²⁰

Other elements found in buckwheat also contribute to buckwheat’s ability to lower blood pressure, including its abundant supply of magnesium¹² and its extremely rich fiber content. The high fiber content additionally promotes cardiovascular health by decreasing inflammation, LDL cholesterol, and total cholesterol.¹⁷

Remarkably, scientists have found that the protein in buckwheat has a unique amino acid composition that allows it to act similarly to fiber. This amino acid profile provides special biological activities that include cholesterol-lowering and antihypertensive effects.⁶

Researchers in China confirmed these effects when they investigated the relationship between buckwheat (and oat) consumption and cardiovascular disease risk factors in an ethnic minority in China. Their research, which was published in the American Journal of Clinical Nutrition, found that a greater regular intake of buckwheat correlated with lower LDL cholesterol levels, reduced total cholesterol, and a higher ratio of HDL-to-total cholesterol. The study concluded that buckwheat has the potential to prevent and treat both hypertension and high blood cholesterol (together referred to as hypercholesterolemia).⁶

The flavonoid rutin has often been recommended to people with varicose veins as a means of promoting vascular health. In fact, one hypothesis is that varicose veins and spider veins may be caused by a deficiency of rutin in the diet.¹⁸

Rutin strengthens weak capillary walls. It has been shown in placebo-controlled studies to improve signs and symptoms of venous insufficiency, including hemorrhoids and retinal hemorrhage, a condition that can lead to partial or even complete blindness.^20,21

Protection Against Diabetes

Both animal and human studies reveal that buckwheat flour can improve diabetes, as well as obesity, which is a risk factor for diabetes.⁵

One of the ways buckwheat can have a beneficial effect on diabetes is by blocking the digestion of sucrose (table sugar). It does this by inhibiting the activity of sucrase, the name given to a number of enzymes that convert sucrose to fructose and glucose.²

Canadian scientists conducted a placebo-controlled study to investigate buckwheat’s ability to manage diabetes. They administered buckwheat seed extract to rats that had chemically induced diabetes. When blood glucose levels were assessed at 90 minutes and 120 minutes after administration, the placebo group showed no change. By contrast, the buckwheat group was found to have blood glucose levels that were 12-19% reduced.³ The researchers attribute this effect to the buckwheat compound D-chiro-inositol, which is believed to play a significant role in glucose metabolism and cell signaling.

In fact, other studies have shown that D-chiro-inositol may make cells more sensitive to insulin. It appears to mimic the activity of insulin and may, therefore, lower blood levels of glucose.^2,3

Blocking The Effects of Polycystic Ovary Syndrome

The D-chiro-inositol in buckwheat may offer a powerful benefit for women with polycystic ovary syndrome (PCOS), a condition of hormonal imbalance that is common in women of reproductive age. This syndrome is generally associated with increased insulin resistance, which scientists believe results from an inability to properly utilize D-chiro-inositol.²²

In double-blind studies, when women with PCOS received D-chiro-inositol, they experienced an increase in insulin sensitivity, a reduction in testosterone, and an increase in ovulation frequency.^23,24

One study showed that it could also help normalize glucose levels in women with this condition.¹

Inhibiting Arthritis And Other Inflammatory Conditions

The rich supply of rutin in buckwheat could improve arthritis and other inflammation-related conditions by inhibiting the inflammatory response.

Cells known as macrophages are the major source of inflammatory mediators during an immune response. Remarkably, a study published in the journal Arthritis Research & Therapy demonstrated that rutin has the potential to modify the expression of proinflammatory genes in human macrophages. The researchers found that, in vitro, rutin can reduce human macrophage-derived inflammatory mediators. They also found that, in rats, rutin can inhibit the clinical signs of chronic arthritis.⁷

Another study found that oral administration of rutin can attenuate inflammatory bowel conditions such as colitis. This effect was related to rutin’s capacity to boost glutathione levels in the colon. This in turn reduces tissue damage from intestinal oxidative stress, characteristic of inflammatory colitis.²⁵

Suppressing Allergic Responses

Certain grains found in the grass family contain the protein gluten, which can trigger digestive tract upset and diarrhea in susceptible individuals. This includes those with the relatively rare condition known as celiac disease, as well as gluten-intolerant people. Symptoms can include headaches, abdominal pain and distension, flatulence, irritable bowel syndrome (IBS), depression, and skin rashes.

Buckwheat, however, is completely gluten-free, making it a great grain substitute for gluten-sensitive persons.

Those with allergies not related to gluten may be interested in buckwheat for a different reason. Research published in the journal International Immunopharmacology suggests that buckwheat extract has a strong antiallergic activity, which may be the result of buckwheat’s capacity to inhibit histamine release and block cytokine gene expression in mast cells.⁸

Possible Anticancer Activity

Early evidence suggests that buckwheat may exert novel mechanisms that help inhibit the origins of cancer.

One study in the Journal of Nutrition found that buckwheat protein extract provides protection against colon carcinogenesis in rats by reducing cell proliferation.²⁶

A later study examined the effects of buckwheat protein polysaccharides on leukemia cells. The researchers found that these compounds reduced leukemia proliferation by an important process known as cell differentiation. Inducing differentiation of leukemic cells has become one of the most important therapeutic approaches for curing this form of cancer.²⁷

Summary

Buckwheat is a highly nutritious, gluten-free grain substitute that contains a rich supply of soluble and insoluble fiber, complete protein, and novel phytocompounds. Two compounds in particular—rutin and D-chiro-inositol—have shown remarkable activity against cardiovascular disease, diabetes, arthritis, and allergies, and may inhibit carcinogenesis.

Due to its modestly high calorie content, buckwheat should be used as a healthy food choice and not intentionally ingested as a supplement to one’s diet.

If you have any questions on the scientific content of this article, please call a Life Extension^® Health Advisor at 1-866-864-3027.

References

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