Amy P. Campbell, MS, RD, CDE, and Richard S. Beaser, M.D.
The weeks excerpt answers the following questions:
- When to take vitamins?
- Who should take vitamins?
- Can chromium really lower blood sugars?
- Is vitamin E recommended?
- Is too much vitamin E harmful?
- Does cinnamon really work?
- What dose of cinnamon is most effective?
- Can magnesium increase insulin sensitivity?
Vitamins, Minerals and Supplements
If the diet is adequate, there may be no need for additional vitamins and minerals. It is important to determine whether your patients are taking any dietary supplements. Though you need to offer advice if any supplements they may be taking are harmful, be mindful not to be judgmental, as it is important for patients to be involved in their self-treatment. In addition, many people take supplements based on their cultural beliefs about nutrition and medicine.
Patients who are at risk for nutritional deficiencies and for whom you might want to suggest a vitamin supplement are vegetarians, the elderly, pregnant or lactating women, those with poor metabolic control, those who experience malabsorption, who have had myocardial infarctions or congestive heart failure, or people who are following very-low-calorie diets.
Women with diabetes may need a calcium and vitamin D supplement to optimize bone health and prevent osteoporosis. Some younger women may need an iron supplement if they have or are at risk for iron-deficiency anemia.
A study by researchers at the Beetham Eye Institute at Joslin Diabetes Center showed high doses of vitamin Esupplements to be effective in improving blood flow in the retina of the eye and the kidneys in patients with type 1 diabetes. Caution is recommended, however, in suggesting vitamin E supplements to diabetes patients, as further studies are needed to confirm these findings. Furthermore, a recent study indicates that high doses of vitamin E may actually be harmful to older people.
When treating people with diabetes, keep in mind that both deficiencies and overdoses of some of the B vitamins can cause symptoms similar to diabetic neuropathies.
Those studying chromium have found that, in the Chinese population, supplements up to 200 mcg improved blood glucose levels, which makes sense, given that chromium is a trace mineral that helps insulin do its job. However, another, more recent study has shown that chromium given in doses of either 500 or 1000 mcg did not improve blood glucose control in obese patients with poorly-controlled type 2 diabetes. The chromium did not produce any greater reduction in A1C levels than a placebo. Furthermore, true chromium deficiencies are rare, and there is some doubt that chromium will have any benefit unless a deficiency is present. The faddists’ suggestions to use chromium as an antidiabetic agent may also carry some risk — chromium excess has been shown to be harmful in lab animals.
Cinnamonis a popular spice used extensively to season many different foods. Over the past several years, cinnamon has been used as a dietary supplement by many people with diabetes to help lower blood glucose levels. Phenols, antioxidants found in this spice, are involved with glucose transport and curbing inflammation in the body. In addition, polyphenol, another antioxidant found in cinnamon, has insulin-like properties which help to lower glucose levels. One study involving people with type 2 diabetes who were given various doses of cinnamon (1, 3 or 6 grams) showed beneficial effects: All doses of cinnamon lowered fasting glucose, LDL cholesterol, total cholesterol and triglyceride levels. Cinnamon is considered to be quite safe, with no significant harmful side effects, other than possibly causing an allergic reaction in certain individuals. However, the use of cinnamon oil should be avoided due to its toxic properties. At this time, there is no standard recommendation for dosing for cinnamon, but research indicates that one gram (1/5th of a teaspoon) of cinnamon is a reasonable starting dose. Type 2 diabetes patients interested in trying cinnamon should be encouraged to monitor glucose levels carefully, noting any episodes of hypoglycemia that might warrant a medication adjustment.
People who are magnesium-deficient may see an improvement in their blood glucose once they begin taking magnesium as a supplement. Magnesium is known to increase insulin sensitivity. Poor metabolic control can lead to losses of magnesium in the urine. The daily value (DV) for magnesium is 400 mg. Because it is rare that people will obtain all of their vitamins and minerals from food sources, it’s good practice to recommend a multivitamin/mineral supplement to adult patients with diabetes. Men and postmenopausal women should aim to choose a supplement without iron.
Both the American Diabetes Association and the American Heart Association recommend keeping sodium intake to no more than approximately 2300 mg per day, which amounts to a teaspoon of salt. Because many people with type 2 diabetes have either high blood pressure or are salt sensitive (i.e., more likely to develop high blood pressure), it’s recommended that these people be educated on ways to reduce sodium intake in the diet. Sodium intake may need to be adjusted based on other medical conditions that might be present such as hypertension or hypotension.
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Professionals must use their own professional medical judgment, training and experience and should not rely solely on the information provided in this book to make recommendations to patients with regard to nutrition or exercise or to prescribe medications.
This book is not intended to encourage the treatment of illness, disease or any other medical problem by the layperson. Any application of the recommendations set forth in the following pages is at the reader’s discretion and sole risk. Laypersons are strongly advised to consult a physician or other healthcare professional before altering or undertaking any exercise or nutritional program or before taking any medication referred to in this book.