No matter how well I seem to be doing on my diet, every month right before my I get my period I become irritable and bloated and have unbearable cravings; then, when I give in to them, I get even more depressed than I already am. Is this all in my head? Or is there something I can do about it?

If there's any one subject that seems to come up with precision regularity during the three years I've been doing the iVillage Shape Up program, it's got to be the dreaded PMS. I can't think of anything that has derailed more good intentions than the multi-symptomed nightmare that used to be euphemistically referred to as "that time of month." Experts are hardly in agreement about the causes and treatments of PMS, but let me share with you what, in my opinion, is the best available information.

Up to 150 different symptoms have been linked with PMS. They can range from barely noticeable to downright debilitating. And to this day, although PMS has been a well-researched entity since at least the 1980s (if not before), many physicians still believe that it doesn't really exist and that it is "all in your mind."

Well, it's not.

Before your period, there are powerful hormonal upsets that influence mood, craving and water retention and, for some people, create maddeningly difficult emotional personality changes. There is no single cause that explains PMS in every case. PMS seems to have at least four "types." Obviously each of these "types" is shorthand for a constellation of symptoms, but here's an easy way to remember them: A for anxiety, B for bloating (sometimes called H for hydration), C for cramps and D for depression. Some folks like to add the all-too-familiar fifth type, E (for everything).

That there is a nutritional link to PMS seems almost unarguable. Researchers have shown that the typical PMS sufferer consumes 275 percent more sugar, 62 percent more refined carbohydrates, 78 percent more sodium, 79 percent more dairy products, 52 percent less zinc, 77 percent less magnesium and 53 percent less iron than non-PMS sufferers.

Is there a nutritional "cure" for this complex hormonal-neurotransmitter stew? Well, I don't know anyone who would make that claim, but there sure are some prudent strategies. Here are some of the best.

• Cut out sugar. Symptom-free women consume far less refined sugar and refined carbohydrates (and dairy products) than those with symptoms.
• Cut out coffee. Among other things, caffeine suppresses the neurotransmitter adenosine, which in turn calms nerve receptors. Without adenosine, nerve receptors can become overly reactive, leading to irritability, mood swings and a worsening of symptoms.
• Exercise. It promotes both circulation and the removal of toxins from the body, plus it raises the level of endorphins, which have a relaxing and mood-improving effect.
• Reduce stress. Do whatever it takes, but take this mandate seriously. Part of that is getting enough sleep. No kidding.
• Include soy products in your diet, particularly the fermented kind such as miso and tempeh.
• Supplement with B-6, magnesium and evening primrose oil. Although less-than-optimal intakes of many nutrients may make symptoms worse, nearly everyone agrees that these three are crucial. A "PMS cocktail" I frequently recommend as a place to start is 1,000 mg of evening primrose oil, 400 mg of magnesium and 100 mg of B6, taken twice a day, beginning about 10 days before your period.
• Consider chasteberry. Also known as Vitex, this is the number one herb used throughout Europe to help relieve symptoms of PMS. One of the things it does is act directly on the pituitary gland to stimulate the secretion of leutinizing hormone, which in turn stimulates the secretion of progesterone, helping to create a more hormonally balanced state. And it can be used along with the supplements mentioned.
• Some studies have shown that calcium supplementation may help with PMS symptoms (about 1,000 mg daily). Supplements may be better than dairy, for reasons mentioned above.
• Reduce alcohol. Seriously.
• Get some sun. Lack of sunlight (or full-spectrum light) seriously reduces serotonin levels, contributing to depression and lack of energy.

Above all, be good to yourself, experiment with these strategies and give them enough time to work.

It'll be worth the effort.

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