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You Can Prevent PMS From Destroying Your Diet

PMS removes a sense of emotional well-being.

Dieters face situations that threaten their willpower or even their ability to get the foods they are supposed to be eating. Catered business lunches, Sunday dinners at a relative's home, birthday parties, lack of time to go to the supermarket: These are only a handful of the obstacles that stand between the dieter and their food plan. These problems are so common that advice on how to deal with them is standard in most weight-loss books and group programs.

But there is a threat to the female dieter that cannot be overcome by food lists and willpower—and that is premenstrual syndrome (PMS).

PMS is a monthly disturbance in mood and appetite brought on by hormonal changes a few days before menstruation. Not all women experience it and even those who do may find that certain months are worse than others. But when it hits, it can be like a tidal wave, knocking down eating control, exercise programs, and emotional stability. PMS removes a sense of emotional well-being and deposits in its place anger, irritability, confusion, exhaustion, and depression. These unpleasant moods are often accompanied by an impulsive, uncontrollable need to eat. The foods craved during the last days of the menstrual cycle fall either into the greasy, salty, crunchy, starchy category or the fatty, creamy, sugary category.

Although it has been clear for millennium that something was happening to women each month that altered their mood, sleep, energy and eating, the explanations were often closer to witchcraft than science. Even in the latter part of the last century, remedies were suggested that turned out to be totally ineffective or actually worsened the condition. For instance, chocolate craving is a hallmark of PMS—as in, "I could kill for chocolate." So well-meaning PMS therapists assumed chocolate was causing PMS and forbade it. It was believed that water on the brain (this was actually mentioned in the scientific literature) was affecting mood so diuretics were prescribed. Because the hormone progesterone increases in relation to estrogen at the end of the menstrual cycle, well-intentioned physicians prescribed even more to offset the PMS symptoms. This went on until carefully controlled research showed that progesterone made the symptoms worse. And even today, women's magazines tell their readers to exercise, drink water, and eat fruits and vegetables to reduce the severity of the symptoms. This advice sounds good but it is impossible to follow by women who are exhausted, weepy, angry, and craving salty, greasy french fries.

Women with premenstrual syndrome do indeed eat more at that time than during the other weeks of their menstrual cycle. We monitored the calorie intake of women during their menstrual cycle in a study carried out at the Massachusetts Institute of Technology (MIT). Women lived in the Clinical Research Center during the first few days of their cycle and then returned three weeks later when they had PMS. The normal weight volunteers consumed about 1,100 calories more when they were premenstrual than they did at other times of the month. And to no one's surprise, the extra calories came from chocolate, potato chips, cookies, and crackers.

Our volunteers had no problem returning to their healthy way of eating once the PMS passed and they easily lost the pound or two they may have gained from their premenstrual munching. But for dieters, PMS poses more than a temporary halt in their weight loss. Premenstrual syndrome may cause the dieter to abandon her diet.

One of our weight-loss clients described the effect of PMS on her weight loss: "For three weeks I am in control, and my food choices follow the diet plan exactly. Then one day, during the fourth week of my menstrual cycle, I wake up with an uncontrollable urge to eat junk food. I simply can't stop myself. This goes on for three or four days until I get my period. So, of course, my diet is blown, and I am three or four pounds heavier than I was a week earlier."

Yet it is possible to stop PMS from destroying a diet.

The solution is to increase the production of serotonin, the brain chemical involved in regulating mood and weight. We discovered at MIT that serotonin activity is diminished during PMS so simply increasing serotonin production reduces the unpleasant mood and overeating during this time of the month.

Increasing serotonin is easy. The brain chemical is made when a non-fruit carbohydrate is eaten. Here is all that needs to be done:

Twice a day (or more if necessary), eat a snack containing 30-35 grams of a starchy or sweet carbohydrate. Choose foods that have no more than 2 grams of protein and 2 grams of fat. Protein prevents serotonin from being made, and fat just adds calories.

Eat the foods on an empty stomach or three hours after a meal.

The snacks should be regarded as edible therapy for the PMS, not as a source of nutrition. Make sure you take your usual vitamin and calcium supplements and eat as many fruits, vegetables, low- or non-fat dairy products, and lean protein as your PMS cravings will allow.

Good snack choices include popcorn, fat-free fudge sauce (for PMS chocolate cravers), sweetened breakfast cereal, an English muffin with jam, oatmeal with brown sugar, graham crackers, low-fat granola bars, very low-fat ice cream or frozen yogurt, low-fat rice or soy crackers, pretzels, low-fat meringue cookies, low-fat biscotti, and cotton candy (in case you have PMS while at a county fair).

A few caveats:

  • Alcohol is not a substitute for the carbohydrate.
  • Eating fruit will not lead to serotonin production.
  • Soda and other foods made with high fructose corn syrup sweeteners do not lead to serotonin production.
  • Restrain yourself from munching on fat-filled brownies, chips, ice cream, and chocolate. Your brain doesn't know the difference but your scale will.

The effects of eating a low- or fat-free carbohydrate snack on your mood and appetite should be felt within 45 minutes or even sooner. After eating the snack, relax, meditate, read a book or contemplate that when you reach menopause, all this will be over.

© 2010 Judith J. Wurtman, Ph.D., co-author of The Serotonin Power Diet: Eat CarbsNature's Own Appetite Suppressantto Stop Emotional Overeating and Halt Antidepressant-Associated Weight Gain.