The nutritional approaches I discuss below are intended to help offset side effects associated with various types of treatment for Graves’ disease. In addition to keeping you well during and after your course of therapy for this disease, my strategies will also improve your overall health and feeling of well-being.
VITAMINS AND MINERALS Antioxidants
Studies suggest that hyperthyroidism is associated with a decrease in antioxidants and an increase in oxidative stress brought on by free radical molecules. Free radicals are highly reactive oxygen molecules that are produced by normal body processes. Dietary antioxidants such as vitamins C and E and beta-carotene quench harmful free radicals and prevent them from causing damage to body cells.
Studies that measure levels of antioxidant nutrients in the blood and thyroid tissue of women with Graves’ hyperthyroidism have observed decreased levels of beta-carotene.4 Another study looked at the effect of a daily vitamin C supplement in 24 women undergoing anti-thyroid drug therapy for Graves’ disease.5 At the beginning of the study, the researchers found that, compared to healthy women who served as controls, those with hyperthyroidism had higher levels of oxidized compounds and lower levels of antioxidant enzymes in their blood. After taking 1000 milligrams of vitamin C for one month, these women had significant increases in antioxidant enzymes.
Managing Graves Hyperthyroidism Photo Gallery
While the link between antioxidants and hyperthyroidism is preliminary at best, there is no harm in boosting your intake of these nutrients as they have many other potential health benefits. Here’s what you need to know about these nutrients.
Beta-Carotene
This antioxidant is plentiful in dark green vegetables and orange fruits and vegetables. Currently there is no daily recommended intake for beta-carotene, but many experts believe that 5 to 15 milligrams (9000 to 27,000 international units) per day offer plenty of protection. Here are the best food sources:
BETA-CAROTENE FOOD (MILLIGRAMS)
Sweet potato, cooked, 1/2 cup (125 ml) 15
Collard greens, cooked, 1 cup (250 ml) 7
Carrot, 1 medium 5
Squash, winter, 1 cup (250 ml) 5
Apricots, fresh, 3 medium 4
Kale, cooked, 1 cup (250 ml) 3
Spinach, cooked, 1 cup (250 ml) 3
Mango, sliced, 1 cup (250 ml) 2
Nutrient Values of Some Common Foods, Health Canada, Ottawa, 1999.
The body is not very efficient at absorbing beta-carotene from raw foods. For instance, less than 5 percent of carotenoid compounds have been shown to be available in raw carrots. But the good news is you can enhance absorption by cooking your vegetables—even steaming increases the available beta-carotene in carrots and spinach. And you might want to add a little fat to your meal to optimize beta-carotene absorption. Try a little vegetable dip the next time you snack on those baby carrots. Or add a teaspoon or two of olive oil to your sweet potato puree. And forgo the fat-free salad dressing—I’ve always been in favor of using a small amount of the real thing.
If you’re looking for supplemental beta-carotene, buy a multivitamin and mineral with added beta-carotene. Most brands provide 1000 to 10,000 international units (0.5 to 5.5 milligrams). A word of warning to women who smoke: use of separate beta-carotene supplements (not in a multivitamin format) in doses of 20 milligrams per day for five to eight years has been associated with an increased risk of lung cancer in men who smoke.6 While these findings may not apply to women, it makes sense to be cautious. If you are a smoker, I recommend that you avoid beta-carotene supplements and stick to getting your daily fix from foods and a multivitamin pill. A higher risk of lung cancer has not been found in smokers who eat a diet plentiful in beta-carotene-rich foods.
If you do take a separate beta-carotene supplement, be advised that when doses of 30 milligrams per day or more are taken for a period of time, a yellow discoloration of the skin can occur. This adverse effect can even occur when people eat plenty of carrots day after day. The condition is called carotenodermia; it’s considered harmless and disappears when supplements are discontinued.
Vitamin C Graves’ Hyperthyroidism
For the amount of vitamin C women should be getting each day, see the RDA table on page 11 in chapter 1. You’ll find your best food bets in the Vitamin C in Foods table on page 12.
If you don’t eat at least two vitamin-C-rich foods each day, a supplement is a good idea. Keep in mind though that fruits and vegetables contain many other natural chemicals that may work with vitamin C to keep you healthy. So, even if you do take a vitamin C pill, I recommend that you still add foods rich in vitamin C to your daily diet. Here’s what you need to know about vitamin C supplements:
• If you’re looking for the most C for your money, choose a supplement labeled Ester C. Studies in the lab have found that this form of vitamin C is more available to the body.
• If you don’t like to swallow pills and prefer a chewable supplement, make sure it contains calcium ascorbate or sodium ascorbate. These forms of vitamin C are less acidic and therefore less harmful to the enamel of your teeth.
• Take a 500-milligram supplement once or twice a day. There’s little point in swallowing much more at once, since your body can use only about 200 milligrams at one time. If you want to take more, split your dose over the day.
• The daily upper limit for vitamin C has been set at 2000 milligrams to avoid diarrhea.