BOSTON—There are very predictable patterns of nutrient deficiencies in subgroups of primary care patients, many of which can be corrected with inexpensive supplements or relatively minor diet adjustments, said Dr. Judy Shabert, at a conference on alternative medicine and its implications for clinical practice, sponsored by Harvard Medical School.
Dr. Shabert, an ob.gyn. who is also a registered dietitian, and her husband Dr. Douglas Wilmore, senior staff surgeon at Brigham and Women’s Hospital, Boston, shared their observations and strategies to improve nutritional status for the following sub-populations:
• Elderly Patients: In general, people consume progressively less protein as they age. This may reflect financial difficulties, poor dentition or difficulty shopping. Whatever the reason, low protein intake combined with inactivity results in rapid loss of lean muscle mass. “It is scary how much lean tissue people start to lose after age 50,” Dr. Shabert said.
Since key nutrients like vitamin A, B6, and zinc come mainly from high-protein foods, a protein-deficient elderly patient probably lacks these as well. Encourage these patients to eat more lean protein—whichever foods they like and are capable of eating.
But also push them to exercise—even short periods of resistance exercise using soup cans as dumbbells make a difference.
Protein and protein-associated nutrients are essential for good immune function, and many older individuals benefit from supplementation. A landmark 1992 study compared supplementation with essential vitamins and minerals versus placebo in 96 healthy, upper middle-class elderly subjects. Those taking supplements had half as many infections, and used half as many antibiotics over the one-year follow up period (Chandra RK. Lancet 1992;340:1124–27).
Macular degeneration, the most common cause of blindness over age 65 can be prevented by increasing lutein in the diet. This yellow pigment, essential for good macular function, is abundant in apple skins, blueberries, cranberries, spinach, kale and collard greens.
• Familial Atherosclerosis: Dr. Shabert recommended measuring homocysteine levels for all patients with family histories of heart disease. “The lower the homocysteine the better.” Twelve micromoles per liter is normal, but 4–8 micromoles is ideal for patients at high risk. You can help get them there with vitamin B6 (2 mg per day), B12 (2 g per day), and folic acid (400 g per day).
These patients should be on moderately low-fat diets, but make sure they don’t replace the fat with refined carbohydrates and simple sugars. These patients should avoid saturated and partially-hydrogenated fats. Those who eat red meat can lower fat per serving by buying lower grades of meat, which are not necessarily of poorer quality, just not as lipid-rich.
• Osteoporosis: Now that millions of American women take calcium to prevent osteoporosis, it would be nice if they actually absorbed what they took. This depends on vitamin D intake. If your patients are not milk-drinkers, encourage them to drink vitamin-D fortified soy milk or rice milk, or use vitamin D supplements. A daily intake of 400 IU guarantees good calcium absorption in most people. Elderly patients who have little exposure to sunshine should take 600–800 IU per day.
Increasing calcium can create problems of its own unless it is balanced by increased magnesium intake. Calcium and magnesium are antagonistic in terms of absorption; a large rise in calcium will reduce magnesium absorption.
Magnesium deficiency, which Drs. Shabert and Wilmore find to be very common, predisposes people to cardiac arrhythmias, headaches, muscle cramps and constipation. “If it spasms, think magnesium,” Dr. Shabert said. Ideally, calcium and magnesium should be in a 2 to 1 ratio. If you recommend that patients take 1,200 mg of calcium daily to prevent osteoporosis, make sure they also take 600 mg magnesium to maintain the balance.
• Type II Diabetes: For years now, dietary guidelines for type II diabetes have been almost obsessive in limiting fat. Some experts let carbohydrates comprise up to 60% of total caloric intake, so long as this keeps the fat down. The problem is, a high-carb diet increases triglycerides and lowers high-density lipoprotein, particularly in people with insulin resistance.
This realization has prompted diabetologists to re-think the guidelines. Drs. Shabert and Wilmore recommend keeping carbohydrates around 40% of total caloric intake, while letting patients know it is okay to slightly increase protein, mono- and polyunsaturated fats.
There are now two well-designed trials—one focused on type II patients, the other looking at gestational diabetes—that show chromium supplementation can reduce hemoglobin A1c levels. This element seems to affect glucose transport across cell membranes, and seems to increase efficiency of insulin.
Chromium supplementation is worth considering for type II diabetics who are having difficulty maintaining euglycemia despite conventional therapy. The patients in the type II study (Anderson RA et al. Diabetes 1996;45(Supp 2):124A) were taking 400–1,000 mcg chromium per day for four months.
Use of chromium with insulin or oral anti-glycemic drugs obviously requires close glucose monitoring, said Dr. Shabert. While no one is sure about the ideal maintenance dose for chromium, something in the range of 200–400 mcg is appropriate, she said.
Chromium picolinate is the most common form of chromium supplement but recent research has raised some concern. Cell culture studies demonstrated DNA damage to hamster oocytes with high doses of chromium picolinate. However, this has not been demonstrated in other animals or in humans.
THE REDUX: Common, easily reversible nutrient deficiencies lurking among your patients include: protein and protein-associated nutrients (vitamin A, vitamin B6 and zinc) in the elderly; vitamin B6, B12 and folic acid in familial atherosclerosis patients; and vitamin D and magnesium among women taking calcium to prevent osteoporosis. Type II diabetics may see improved glycemic control with chromium supplementation. A 1992 study found that elderly people taking supplements had half as many infections, and used half as many antibiotics over the one-year follow up period.
