Mulberry Helps Control Blood Sugar,and Fight Diabetes

Mulberry Fights Diabetes

The antioxidant, antiatherosclerotic effects of mulberry are gratifying, of course (and here we’re making the assumption that the effects seen in laboratory and animal experiments would be seen in actual human beings as well), but there’s more to the story than that. Mulberry leaves have long been used in Chinese medicine for the prevention and treatment of diabetes, because, as we now know, they contain chemical compounds that suppress high blood sugar levels (hyperglycemia) following a carbohydrate-rich meal.

Controlling blood sugar (glucose) levels is vitally important. When these levels rise sharply, as they do after ingesting foods with a high glycemic index, such as potatoes or sweets, the body responds by producing more insulin to deal with the overload. But if this demand for more insulin occurs too strongly too often, the ability of the pancreas to produce enough insulin may become impaired, and our cells may become resistant to insulin as it tries to do its job of facilitating glucose transport through the cell walls. The result is insulin resistance, a dangerous condition that, if unchecked, leads to type 2 diabetes. Its primary cause is obesity. Generally speaking, if you are obese, your risk for diabetes is high; if not, it’s low (unless you happen to have a genetic predisposition for diabetes).

Mulberry Controls Blood Sugar

Another research group in Japan has found that white mulberry leaves contain compounds that inhibit these intestinal enzymes.3 In experiments with normal rats, they found that certain nitrogen-containing sugars in mulberry-leaf extract, notably one called 1-deoxynojirimycin, strongly inhibited the intestinal metabolism of disaccharides (especially sucrose), thereby restricting the amounts of monosaccharides that entered the circulation. They also found that pretreating the rats with mulberry extract before feeding them carbohydrates significantly suppressed the normal postprandial (after-meal) rise in blood glucose levels.

This beneficial effect occurred in a dose-dependent manner. The doses were, however, very large: 0.1–0.5 g/kg of body weight, which, for a 70-kg (154-lb) human, would be 7–35 g. (A lower dose, 0.02 g/kg, corresponding to 1.4 g for a human, was ineffective.) Nonetheless, the researchers suggested that mulberry extract might be beneficial in preventing human diabetes by suppressing intestinal alpha-glucosidase activities.

Mulberry Protects Blood-Cell Membranes

The researchers were interested in the patients’ erythrocyte membranes because these delicate structures, consisting primarily of lipids (fatty substances, including cholesterol), are subject to peroxidation, a destructive process brought about by the highly reactive molecular species known as free radicals. Such oxidative stress is normally offset by the presence of antioxidants, but the levels of these vital protective compounds are typically below normal in diabetic patients, as mentioned above. The resulting damage to the patients’ erythrocyte membranes can compromise their health in various ways—all part of the scourge of diabetes, in which excessive lipid peroxidation and its destructive effects are characteristic features.

It turned out that mulberry significantly reduced lipid peroxidation in the patients’ erythrocyte membranes, whereas glibenclamide did not. Mulberry also brought about significant reductions in the levels of lipid peroxides in the patients blood plasma and urine. The authors stated:

In conclusion, the present study provides preliminary data that suggest that mulberry therapy is capable of enhancing glycemic control in patients with type 2 diabetes. Our work suggests that serum and erythrocyte membrane lipids of diabetic patients were favorably affected by mulberry therapy.

The solution is obvious. Not so obvious, however, is the fact that there are nutritional supplements, such as mulberry, that can help us fend off diabetes while we strive to follow a healthier lifestyle.

  1. Doi K, Kojima T, Makino M, Kimura Y, Fujimoto Y. Studies on the constituents of the leaves of Morus alba L. Chem Pharm Bull 2001;49(2):151-3.

  2. Doi K, Kojima T, Fujimoto Y. Mulberry leaf extract inhibits the oxidative modification of rabbit and human low-density lipoprotein. Biol Pharm Bull 2000;23(9):1066-71.

  3. Miyahara C, Miyazawa M, Satoh S, Sakai A, Mizusaki S. Inhibitory effects of mulberry leaf extract on postprandial hyperglycemia in normal rats. J Nutr Sci Vitaminol 2004;50;161-4.

  4. Andallu B, Suryakantham V, Srikanthi BL, Reddy GK. Effect of mulberry (Morus indica L.) therapy on plasma and erythrocyte membrane lipids in patients with type 2 diabetes. Clin Chim Acta 2001;314:47-53.

  5. Vijayan K, Srivastava PP, Awasthi AK. Analysis of phylogenetic relationship among five mulberry (Morus) species using molecular markers. Genome 2004;47:439-48.