to the editor: I was pleased to see lifestyle modification, specifically a low-fat vegetarian diet,¹ mentioned as a treatment option for dysmenorrhea in the American Family Physician article, "Dysmenorrhea,"² by Dr. French. Although this intervention is classified as "B" on the “"Strength of Recommendation" scale (as compared with the “A” rating for nonsteroidal anti-inflammatory drugs [NSAIDs]), there are safety advantages to starting with a nonpharmacologic intervention when available. If a nonpharmacologic treatment corrects the underlying cause of symptoms, it may obviate the need for pharmacologic treatment of the resultant symptoms. At a minimum, changes in behavior can be recommended concomitantly with pharmaceutical intervention.

A vegetarian diet has numerous advantages. For example, a companion publication³ to the diet study1 cited above showed that premenopausal women eating a vegetarian diet for five weeks had a significant reduction in low-density lipoprotein (LDL) cholesterol (16.9 percent, P <.001) and a 2.5-kg (5.5 lb) weight loss (P <.001), as compared with women on their customary diet and receiving a placebo supplement. This degree of LDL lowering was 11 times greater than what would be expected by weight loss alone.⁴

A diet change also is typically free of adverse effects. In contrast, cholesterol-lowering drugs, antihypertensives, NSAIDs, and multiple other drug classes are associated with significant risks. Specifically, many patients taking NSAIDs exceed the maximum recommended dosage because of their over-the-counter availability.

There are two apparent biologic mechanisms by which dietary changes influence dysmenorrhea. First, vegetarian diets appear to raise blood concentrations of sex-hormone binding globulin, which binds and inactivates estrogens.⁵ Second, estrogen and progesterone stimulate the endometrium, which is the source of the prostaglandins that are thought to induce ischemia and uterine muscle contraction⁶ and the painful symptoms of dysmenorrhea. Through dietary modulation of estrogen and resultant prostaglandin production, the need for NSAIDs could be minimized.

Many patients would accept, or even prefer, a recommendation of a vegetarian diet over a drug prescription if it was offered by physicians for dysmenorrhea and for conditions such as hypertension, hyperlipidemia, and diabetes. It remains to be seen whether such a diet may be beneficial in reducing risk for other conditions linked to estrogen activity, such as uterine fibroids or hormone-dependent cancers. Much evidence exists to support nutritional interventions as a therapeutic modality for common diseases, and more will continue to emerge to the extent we employ such modalities in the clinical setting.

in reply: Dr. Jaster makes some very good points about the health benefits of a vegetarian diet in addition to its potential to favorably impact dysmenorrhea. I agree that it is appropriate to emphasize this diet when discussing therapeutic options with young women. However, it remains to be seen whether such a major lifestyle change is acceptable and sustainable for many young women. Counseling for a balanced vegetarian diet also is essential. My anecdotal experience is that young women may decide to stop eating meat without eating a balanced diet rich in vegetables and vegetable proteins. Protein requirements are not difficult to cover if dairy products are consumed regularly; otherwise, it does take some planning. Another consideration for young women who pursue vegetarian diets is the risk for iron deficiency anemia. Again, it takes some planning to get enough iron from vegetable sources.