Food fears may
Teens with acne often hear that they need to stop eating such foods as chocolate, sodas, French fries and pizza. Scientific research indicates that this is not true. And food fears taken to extremes can lead to diets that may make acne worse.
Question: Can diet cause or prevent acne?
Answer: Although there is no scientific evidence that snack foods cause or even aggravate acne, some cases may be related to a low intake of certain nutrients. Many vitamins and minerals can affect skin health, so a well-balanced diet can promote healthy skin.
Some specific nutrients may be especially important. In the late 1970's, Dr. G. Michaelsson reported that Swedish teenagers with acne had lower blood levels of three nutrients: zinc, vitamin A and polyunsaturated fatty acids.
Additional research indicated that taking zinc supplements could significantly reduce the severity of acne. But vitamin A supplements did not have the same benefit and any role of polyunsaturated fats is unclear. Also, the amount of zinc taken by teens in Michaelsson's study was too great to take for an extended time.
Q: What is a safe dose of zinc from dietary supplements?
A: The Recommended Dietary Allowance for zinc is 11 milligrams per day for teenage boys and 9 milligrams for teen girls. The recommended upper limit for teens is 34 mg per day. Taking excessive zinc for too long causes serious anemia. Any high-level zinc supplementation should be done only with careful medical supervision.
Q: What foods are good zinc sources?
A: The richest sources of zinc include red meats, certain seafoods and whole grains.
Q: Do vegetarian diets provide enough zinc?
A: Not always. Well-designed vegetarian diets typically provide amounts of zinc that are similar to nonvegetarian diets. But according to the Institute of Medicine, the zinc in vegetarian diets is not absorbed as efficiently as the zinc in meats. Vegetarians may need about 50 percent more zinc to meet their needs. Consequently, extreme vegetarian diets, based primarily on whole grains and legumes, could aggravate acne.
Q: What is a good approach to acne prevention?
A: Because many nutrients are involved in the maintenance of healthy skin, it is very important to maintain a balanced intake of all required nutrients. Also, many of non-nutrient phytochemicals in natural foods may play roles in skin health that are currently unknown.
To accomplish balanced intake, eat a wide variety of wholesome foods. These include whole grains, legumes, colorful fruits and vegetables, lean meats and fish, and low-fat milk products. If the quality of the diet is questionable, taking a standard multiple vitamin and mineral supplement could be beneficial.
Also, consider seeing a dermatologist. Many good medical treatments are available, and not all cases of acne are alike. Early treatment can prevent the permanent scarring that sometimes results.
See the Columnists
section for some past articles.
Alan Titchenal, Ph.D., C.N.S. and Joannie Dobbs, Ph.D., C.N.S. are
nutritionists in the Department of Human Nutrition, Food and Animal
Sciences, College of Tropical Agriculture and Human Resources, UH-Manoa.
Dr. Dobbs also works with the University Health Services and prepares
the nutritional analyses marked with an asterisk in this section.