Seventeen million people in the United States have diabetes, the fifth deadliest disease in the U.S. According to the American Diabetes Association (ADA), 2,200 people are diagnosed with diabetes each day. If untreated, complications that can arise from diabetes include heart disease, stroke, kidney failure, blindness, and neurological disorders (see sidebar on p. 90). Overall, the risk for death among people with diabetes is about twice that of people without diabetes. In 1999, approximately 450,000 deaths occurred among people with diabetes aged 25 years and older—about 19% of all deaths in the U.S. of people aged 25 years and older.
Diabetes affects the body’s ability to produce or respond to insulin, a hormone that allows blood glucose to enter the cells of the body and be used for energy. There are two main types of diabetes. Type 1 usually occurs during childhood or adolescence, and type 2, the most common form of the disease, usually occurs after age 45.
In the U.S., an estimated 850,000 to 1.7 million people have type 1 diabetes. Peak incidence occurs during puberty. The most common form of type 1 results from an autoimmune process in which the body’s immune system attacks and destroys the insulin-producing cells of the pancreas. Therefore, the body cannot produce insulin.
Ninety to ninety-five percent of the 17 million diabetics have type 2 diabetes. People who develop this type are often not aware of it until severe symptoms occur. The risk for type 2 diabetes increases with age. More than 20% percent of the U.S. population aged 65 and older has type 2 diabetes. Type 2 results from the body’s failure to make enough or properly use insulin. Type 2 can often be controlled through losing weight, improved nutrition, and exercise.
A related condition, pre-diabetes, affects an additional 16 million Americans. In March 2002, U.S. Secretary of Health and Human Services Tommy G. Thompson warned Americans of pre-diabetes, which sharply raises the risk for developing type 2 diabetes and increases the risk of heart disease by 50%. HHS and ADA are using the term pre-diabetes to describe an increasingly common condition in which blood glucose levels are higher than normal but not yet diabetic. Studies have shown that most people with this condition go on to develop type 2 diabetes within 10 years unless they make modest changes in their diet and level of physical activity.
There is no specific diet for diabetics, but emphasis is placed on normalizing blood glucose levels. The American Dietetic Association offers these general guidelines, “Eat more starches, such as bread, cereal, and starchy vegetables (6 servings a day or more). Eat more fruits and vegetables (5 a day). Eat sugars and sweets in moderation. Eat less total fat. Eat less saturated fat.” The association also recommends that diabetics consult a registered dietitian to help in their diet planning.
Several products on the market serve to aid diabetics in controlling their diets and blood glucose levels. Mead Johnson Nutritionals, Evansville, Ind., offers its Choice DM® line of products, which includes beverages, nutrition bars, crispy bars, and cereal. The products are specially formulated for flexibility in diabetes self-management.
Ross Laboratories, Columbus, Ohio, offers its Glucerna® line, which includes shakes and snack bars that help balance blood glucose levels. According to the company, the Glucerna shake has clinically demonstrated a lower blood glucose response compared to a standard nutritional beverage.
Following are some ingredients and foods that research indicates may have an effect on blood glucose levels and help the body respond to insulin.
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Several sources of fiber contribute to the total dietary fiber content of diabetic foods such as the Glucerna and Choice lines. The Glucerna shakes contain soy fiber and fructooligosaccharides, which contribute 3.0 g of dietary fiber per 8-floz serving. Glucerna snack bars contain resistant starch, soy fiber, microcrystalline cellulose, and guar gum, which provide 4 g of total dietary fiber per 1.34-oz bar.
“Consumption of dietary fibers that are viscous lowers blood cholesterol levels and helps to normalize blood glucose and insulin levels, making these kinds of fibers part of the dietary plans to treat cardiovascular disease and type 2 diabetes,” according to Marlett et al. (2002). “Considerable experimental evidence demonstrates that the addition of viscous dietary fibers slows gastric emptying rates, digestion, and the absorption of glucose to benefit immediate postprandial glucose metabolism and long-term glucose control in individuals with diabetes mellitus.”
The current defacto definition of dietary fiber states that dietary fiber consists of the remnants of edible plant cells, polysaccharides, lignin, and associated substances resistant to (hydrolysis) digestion by the alimentary enzymes of humans. For labeling purposes, dietary fiber is defined analytically by the current Food and Drug Administration–approved method of measuring total dietary fiber for nutrition labeling (Association of Official Analytical Chemists method 985.29). These definitions, however do not take into account other low-molecular-weight carbohydrates that are not digested by human digestive enzymes such as polyfructans, oligosaccharides and polydextrose, which also exhibit dietary fiber’s beneficial properties.
For example, a large-scale human clinical study (Jie, 2000) confirmed the benefits of one form of polydextrose, Litesse® (Danisco Sweeteners, Ardsley, N.Y.). The study found that Litesse polydextrose aided blood glucose homeostasis because of its low glycemic index.
“One of the major developments in our understanding of the importance of carbohydrates for health in the past twenty years has been the discovery of resistant starch,” said H. de Haen, FAO Assistant Director-General, Economic & Social Dept. at the Joint FAO/WHO Expert Consultation on Human Nutrition in April 1997. Resistant starch is a food starch or starch derivative that the human body cannot digest.
Choice DM Bars are just one of several products that contain resistant starch to help slow the rise in blood sugar. According to Mead Johnson Nutritionals, Choice Bars have been clinically shown to reduce the rise in blood sugar levels, compared with other tested snack bars.
“Resistant starch benefits health because it can replace rapidly digested carbohydrates in foods, thereby lowering the body’s intake and level of blood glucose and preventing blood glucose spiking,” said Rhonda Witwer, Business Development Manager, Nutrition, at National Starch and Chemical Co., Bridgewater, N.J. “The studies with resistant starch are consistent and confirmed. You get lower levels of glucose and lower insulin curves in response to eating foods with high levels of resistant starch.”
High-amylose corn starch is the basis for Novelose® starches, National Starch’s line of resistant starch products. These starches are process tolerant and can be labeled as corn starch. There are 11 published human clinical studies with high-amylose corn starch demonstrating benefits to blood glucose and/or insulin levels. “The amylose enhances the opportunity for retrogradation or crystallization of the glucose polymer, which limits digestibility, reducing the contribution to blood glucose levels,” said Witwer. “Published studies on Novelose 330 starch showed that 50% was digested and 50% was resistant. That confirms that it only partially contributes to the blood glucose level. Novelose 240 and 260 starches also have high levels of resistance and would impact blood glucose similarly.”
“We see that blood glucose is really emerging as a main biomarker for health and wellness,” observed Witwer. “It is not necessarily an indicator for only diabetes. High blood sugar levels can be markers in weight control, heart disease, and energy levels in the general population.”
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The seeds of fenugreek have the most medicinal effects of the plant. Studies indicate that fenugreek has a favorable effect on postprandial glucose levels and lipid profiles. It is a fibrous herb and is believed to decrease the rate of digestion and slow down the rise in blood sugar that accompanies a meal, while helping to increase satiety.
In a placebo-controlled study (Sharma et al., 1990), two doses of 50 g of defatted fenugreek seed powder were given to type 1 diabetic patients for 10 days. Researchers observed that the fenugreek diet reduced fasting blood sugar, improved the glucose tolerance, and caused a 54% reduction in 24-hr urinary glucose excretion. Serum total cholesterol, low-density-lipoprotein and very-low-density-lipoprotein cholesterol, and triglycerides were also significantly reduced. The high-density-lipoprotein cholesterol fraction, however, remained unchanged.
In another placebo-controlled study (Bordia et al., 1997), fenugreek was given to patients with mild type 2 diabetes in a dose of 2.5 g twice daily for 3 mo. The fenugreek significantly reduced the fasting and after-meal blood sugar levels. In severe type 2 cases, blood sugar was only slightly reduced.
Chromium is responsible for maintenance of normal glucose uptake into cells. It aids insulin in blood glucose transport into the cells. Striffler et al. (1999) showed that rats raised on a chromium-deficient diet showed the earliest stage of diabetes—high blood insulin levels. During a glucose tolerance test, rats that got virtually no chromium in their food or water for 3 mo had insulin levels twice as high as a group that got chromium-fortified water or a control group fed a standard chow that contained chromium.
One available form of chromium, chromium tricarnosinate (marketed as CarnoChrome by FutureCeuticals, Momence, Ill.), has been shown to stimulate glucose uptake in skeletal muscle cells. “Chromium tricarnosinate has been studied closely as to the effects it has on glucose metabolism,” said Jeff Van Drunen, FutureCeuticals President and CEO. “It is interesting to find out that glucose transport into living skeletal human muscle cells is greatly increased in the presence of chromium tricarnosinate. Skeletal muscle is the major site of postprandial glucose uptake and metabolism. Insulin activates glucose metabolism in skeletal muscle in vivo and in vitro. In particular, insulin has been shown to activate glucose uptake into skeletal muscle as well as activate glucose oxidation and glycogen synthesis within muscle cells,” he explained. “In recent studies, it has been shown that CarnoChrome at a concentration range of 0.1–10 g/mL greatly improved glucose uptake into skeletal muscle cells both in the presence of insulin and in the absence of insulin. This mechanism of improved glucose transport into skeletal muscle is of key importance for proper glucose metabolism.”
CarnoChrome is a chromium (3+)-tricarnosinate, a 100% water-soluble, bioavailable, and biologically safe form of chromium, said Van Drunen. The natural dipeptide carnosine (N-beta-alanyl-L-histidine), the C-ligand in the compound, is abundant in human muscles and plays an important role as an antioxidant and buffer, and quite possibly as a carrier of chromium (3+) ion. In animal and human studies conducted by the company, CarnoChrome showed the ability to lower triglycerides by as much as 30%. Postprandial glucose levels dropped from 5-30% and fasting glucose levels dropped 16–40%, depending on the level of hyperglycemia. Additionally, in a controlled human trial, CarnoChrome had been shown to improve the condition of insulin resistance.
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Biotin is also believed to help improve blood sugar control. In the body, it acts as a conenzyme in fat and carbohydrate metabolism. Koutsikos et al.(1996) administered 50 mg of biotin by intravenous injection to 11 patients on regular hemodialysis. Patients received the injections three times a week for 2 mo. Three out of four patients with abnormal oral glucose tolerance became normal after biotin treatment. According to the researchers, “the results offer support to the beneficial effect of biotin in experimental or clinical diabetes mellitus, and argue for the involvement of biotin in glucose metabolism.”
McCarty (1999) concluded that 3 mg of biotin taken orally three times a day can substantially lower fasting glucose in type 2 diabetics, without side effects.
Two studies are currently looking at the effects of biotin and chromium picolinate. At the University at Buffalo, the State University of New York, Christine Pelkman, Assistant Professor of Physical Therapy, Exercise, and Nutrition Sciences, is conducting a study designed to confirm earlier findings that Diachrome™, a patented combination of chromium picolinate and biotin, reduces the elevation in blood sugar levels caused by foods containing carbohydrates.
“This study will evaluate the blood sugar response in people with diabetes, before and after taking Diachrome, and its action of improving carbohydrate metabolism,” stated Gail Montgomery, President and CEO of Nutrition 21, Purchase, N.Y., the patent holder and supplier of the combination. “We would also expect that it will lower the glycemic response to high-carbohydrate foods in normal populations, an important factor in the development of diabetes and obesity.”
Nutrition 21 has also launched a broad collaborative initiative to evaluate the clinical benefits of the combination. In this study, “The Patient Experience Program,” diabetes educators representing more than 20 managed-care organizations, hospitals, clinics, and government agencies will provide, to more than 500 patients nationwide, patient-care kits that include a 3-mo supply of Diachrome and patient education literature supplied by ADA. Nutrition 21 expects to announce interim results from the first phase of this study this fall.
Cinnamon contains an active compound, methylhydroxy chalcone polymer (MHCP), that may increase glucose metabolism. Agricultural Research Scientists Richard A. Anderson, Walter F. Schmidt, C. Leigh Broadhurst, and Marilyn M. Polansky, identified MHCP in cinnamon and found that it made fat cells more responsive to insulin (McBride, J. 2000). They tested approximately 50 plant extracts and found that MHCP increased glucose metabolism roughly 20-fold in a test-tube assay of fat cells. In addition, MHCP prevented the formation of damaging oxygen radicals in a blood platelet assay. “That could be an important side benefit,” noted Anderson. “Other studies have shown that antioxidant supplements can reduce or slow the progression of various complications of diabetes.”
MHCP and other active compounds are water soluble and are not found in the spice oils sold as food additives. Anderson pointed out that the water extract reduced blood pressure in hypertensive rats even before it increased insulin sensitivity. And compounds in a water extract are less likely to be toxic in large doses than those in an oil extract, he said.
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Attele et al. (2002) reported that ginsenosides, the active ingredients in ginseng, may help to control blood sugar. Using an extract from the berries of Panax ginseng, ginsenoside Re was evaluated for its possible anti-obesity and anti-hyperglycemic effects. The scientists injected obese diabetic mice with ginsenoside Re for 12 consecutive days. On the 12th day, the mice began to have normal glycemic levels as well as an improvement in glucose tolerance. This progression in the blood glucose levels was linked to a significant reduction in serum insulin levels in fed and fasting mice. In addition, the extract-fed mice also lost a considerable amount of weight, which was associated with an increase in energy expenditure and an increase in body temperature. Serum cholesterol levels were also reduced.
Overweight young adults who drink and eat more dairy products may be less likely to develop insulin resistance syndrome (IRS), which has been linked to risk factors for type 2 diabetes and cardiovascular disease, according to results of a study by Pereira et al. (2002). The researchers examined the association between intake of dairy products and incidence of IRS among 3,157 adults, both black and white, aged 18–30 years who were participants in the Coronary Artery Risk Development in Young Adults (CARDIA) Study. CARDIA is a multicenter population-based prospective study of cardiovascular disease risk factors involving participants from four study centers located in Birmingham, Ala., Chicago, Ill., Minneapolis, Minn., and Oakland, Calif. The participants were followed for ten years by clinical examinations, questionnaires for demographic and behavioral (e.g., physical activity, smoking) information, and the CARDIA Diet History, which asks participants about usual dietary practices and obtains a quantitative food frequency for the past 28 days.
Dairy products were identified as any items reported during the diet history interview that were either 100% dairy (e.g., milk) or included dairy as one of the main ingredients. The most frequently consumed dairy product at the baseline examination was milk and milk drinks, followed by butter, cream, and cheeses.
“Dairy consumption was inversely associated with the incidence of all IRS components among individuals who were overweight but not among leaner individuals,” the researchers reported. “The adjusted odds of developing IRS were 72 percent lower among overweight individuals in the highest (35 or more times per week) compared with the lowest (less than 10 times per week) category of dairy consumption. Each daily occasion of dairy consumption was associated with 21 percent lower odds of IRS. These associations were similar for blacks and whites and for men and women,” the authors noted. “Our study suggests that dietary patterns characterized by increased dairy consumption may protect overweight individuals from the development of obesity and the IRS, which are key risk factors for type 2 diabetes and cardiovascular disease.”
Two recent studies indicate that moderate alcohol consumption may have positive effects on diabetic heart risk and reduce the risk of diabetes in postmenopausal women. Wakabayashi et al. (2002) reported that light to moderate drinking can reduce the risk of arterial disease in people with type 2 diabetes. Arterial stiffness is related to increased risk of athersosclerosis. The researchers looked at the alcohol consumption of 194 diabetic volunteers. Results suggested that the light drinkers, defined as those who typically consume up to two drinks per day, had less aortic stiffness than both the nondrinkers and the heavy drinkers. Heavy drinkers, however, had a much higher risk of arterial stiffness, and also typically had higher blood pressure and blood triglyceride levels than both the nondrinkers and the moderate drinkers.
Davies et al. (2002) looked at the effects of daily moderate alcohol consumption on fasting insulin and glucose concentrations and insulin sensitivity. The team recruited 63 healthy postmenopausal women and randomly assigned them to consume 15 or 30 g of alcohol (in an orange juice and ethanol mixture) per day for an eight-week period as part of a controlled diet. Another randomly assigned group consumed no alcohol at all during the period and were given an isocaloric beverage.
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The group that consumed 30g/day of alcohol reduced fasting insulin levels by 19.2% compared to the no-alcohol group. Insulin sensitivity was increased by 7.2%. The team stressed that the trial had been carried out on only a small number of participants and that more research was necessary to confirm the findings.
It should be noted that none of these ingredients or foods are currently promoted to treat or prevent diabetes. The supporting research for some of these ingredients or foods is still young, but they do show promise for the future.
The Impact of Diabetes
Heart disease. Heart disease is the leading cause of diabetes-related deaths.
Stroke. The risk for stroke is 2–4 times higher among people with diabetes.
High blood pressure. About 73% of adults with diabetes have blood pressure greater than or equal to 130/80 mm Hg or use prescription medications for hypertension.
Blindness. Diabetes is the leading cause of new cases of blindness among adults 20–74 years old.
Kidney disease. Diabetes is the leading cause of treated end-stage renal disease, accounting for 43% of new cases. In 1999, 38,160 people with diabetes began treatment for end-stage renal disease and 114,478 people with diabetes underwent dialysis or kidney transplantation.
Nervous system disease. About 60–70% of people with diabetes have mild to severe forms of nervous system damage. The results of such damage include impaired sensation or pain in the feet or hands, slowed digestion of food in the stomach, carpal tunnel syndrome, and other nerve problems. Severe forms of diabetic nerve disease are a major contributing cause of lower-extremity amputations.
—From American Diabetes Association
by LINDA MILO OHR
Attele, A.S., Zhou, Y.P., Xie, J.T., Wu, J.A., Zhang, L., Dey, L., Pugh, W., Rue, P.A., Polonsky, K.S., and Yuan, C.S. 2002. Antidiabetic effects of Panax ginseng berry extract and the identification of an effective component. Diabetes 51: 1851-8.
Bordia, A., Verma, S.K., and Srivastava K.C. 1997. Effect of ginger (Zingiber officinale Rosc.) and fenugreek (Trigonella foenumgraecum L.) on blood lipids, blood sugar and platelet aggregation in patients with coronary artery disease. Prostaglandins, Leukotrienes and Essential Fatty Acids 56: 379-384.
Davies, M.J., Baer, D.J., Judd, J.T., Brown, E.D., Campbell, W.S., and Taylor, P.R. 2002. Effects of moderate alcohol intake on fasting insulin and glucose concentrations and insulin sensitivity in postmenopausal women: A randomized controlled trial. J. Am. Med. Assn. 287: 2559-2562.
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Pereira, M.A., Jacobs, D.R. Jr., Van Horn, L., Slattery, M.L., Kartashov, A.I., and Ludwig, D.S. 2002. Dairy consumption, obesity, and the insulin resistance syndrome in young adults: the CARDIA Study. J. Am. Med. Assn. 287: 2081-9.
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