When Mary and I sat down to review the food diary she had been keeping for a month, I have to admit that many of the meals she described sounded delicious. But they wouldn’t be first on my list to help reach the goal of evening out her mood swings, lessening her menstrual cycle irregularity, and remedying her drop in sex drive, which were the symptoms she most wanted to relieve. We were also aiming to protect her heart, since her father’s life ended relatively early with a fatal heart attack.

Mary made many of her decisions about food in restaurants, lunches with clients and fund-raising dinners (where she thought she had no choice about what was served) are a regular part of her calendar. A month earlier, she had decided to try natural hormone replacement therapy to help with her symptoms. Since she chose to use estriol, a form of estrogen that does not provide cardiovascular protection, I also wanted to work more with her on planning meals.

I didn’t want to give Mary the impression that choosing healthier foods would mean meals that were dim in color and lacking in flavor and appeal, not at all. We started our conversation by looking at ways she could get more plant-based foods into her diet, particularly phyto-sterols.

Phytosterols are the category of foods that helps to balance our hormonal system by regulating the levels of hormones that are too high and stimulating those that are too low. Phytosterols include foods that contain phytoestrogens, substances that can act like estrogens in the body or affect the way our bodies metabolize this hormone. Adding more of these foods to our meals and snacks during our forties brings benefit to our overall health in addition to minimizing some symptoms of perimenopause.

Soybeans and soy products are rich in compounds that can lower cholesterol, reduce our risk of heart disease, and boost our resistance to certain types of cancer. Eating more soy products during our forties provides us with the added benefit of potentially reducing hot flashes and adding a protein to our diets whose absorption does not leach calcium, as the breakdown of meat and other animal proteins does.

I didn’t recommend that Mary begin with soy, mostly because she was unfamiliar with soy foods and would feel more comfortable choosing foods she knew. I suggested that she think more about fruits and vegetables as a way to improve her health. “Many common fruits and vegetables are phytosterols that exert and balance the effects of estrogen and progesterone,” I told Mary. “You can add combinations of whole grains and legumes for protein and fiber, and to help fill you up.”

I reminded Mary to scan restaurant menus differently and think more in terms of ordering several side dishes, such as a vegetable, a baked potato, a small salad, rice, or beans, rather than an entree. I also suggested that Mary ask her assistant to call ahead when she was attending a fund-raising luncheon or dinner and request a vegetarian plate. “Almost all banquet halls and hotels are willing to accommodate these requests,” I said, “and the special plates are generally much healthier for you. Even at a dinner when everyone is being served at once, you just have to remind the person serving that you requested a special plate, and they’ll get it for you.”

“Yes, I’ve seen people do that,” Mary said. “I’ll just have to think ahead a little more.”

“Keep your food diary for another month with your symptom chart. I think you’ll see a change in your mood and energy levels, in response to your eating more vegetables and fruit instead of meat and cheese.” In another month, Mary came back to say that yes, she did notice a change in the way she felt. “I think it has really made a difference to have a vegetarian dinner whenever I can,” she told me. “I used to go home from those events feeling so sluggish and heavy. I thought it was the long-winded speeches, but it was the food!”

This time I suggested that Mary add vanilla-flavored low-fat soy milk to her morning coffee, or put it on whole-grain cereal. One step at a time, she moved toward including other soy foods in her diet. My patient Sharon made time to enjoy cooking and was able to try several soy foods within a month. She too has low-fat soy milk on cereal for breakfast, tosses roasted soy nuts on salads, and “hides” tofu in pasta sauces, on pizza, and in the tuna sandwiches her children eat. Her toddler loves muffins and pancakes, so Sharon varied two of her standard recipes to include soy flour and soy milk. “Nobody in the family even realizes we’re eating more healthy foods now than we ever have,” she said.

A good daily target amount of isoflavones is about 50 mg. To reach that amount, start with the soy foods that are highest in isoflavones, such as soy milk and tofu. Check the labels, and look for brands that list their isoflavone content. Soy oils and sauces are relatively low in isoflavones.

Another health-enhancing compound found in soy is genistein, a type of isoflavone that may protect against cancer. The soy-rich Asian diet may be one of the primary reasons for significantly lower rates of breast and prostate cancer in Japan and other Asian countries. Researchers are still investigating the cancer-fighting potential of this substance, but indications are very promising that it can block cancerous cell growth or inhibit enzymes that cause malignant cells to divide.