After her first child was born, Judy Backoff of Columbus, Ohio, turned to the low-carb, high-fat Atkins diet to lose weight, but it left her with side effects she didn’t expect: fatigue and crummy moods.

“It was a disaster,” she recalls. “I was so tired I’d just collapse on the bed in the afternoon. Worst of all, my milk turned foul. My infant refused to nurse. After quitting Atkins, I regained my energy, and I nursed my subsequent two children happily and healthfully for a full year. I always regretted that diet.”

Ms. Backoff’s emotional side effects are more common than many dieters realize, asserts Dr. Judith Wurtman, clinical researcher at Massachusetts Institute of Technology. She and colleagues have spent years studying the link between diet, emotions, and the brain, and have found that carbohydrates – especially fiber-rich, complex carbs like fruits, vegetables, and whole grains – are essential for good mood.

SEROTONIN

Research indicates that when people stop eating carbohydrates, their brains stop regulating serotonin, a chemical that elevates mood.* “Serotonin is essential to keep your moods regulated,” states Dr. Wurtman, director of the Women’s Health Program at the MIT Clinical Research Center.

Indeed, many antidepressant medications are designed to make serotonin in the brain more active. Carbohydrates raise serotonin levels naturally and act like a natural tranquilizer, Dr. Wurtman asserts. “You don’t need drugs, you need a potato.”

Women tend to be more vulnerable because they don’t have as much serotonin as men, “so as women deplete their serotonin by following the South Beach or Atkins diet, they are more likely to get depressed,” states Dr. Wurtman.

CARBOHYDRATE CRAVERS

Also vulnerable are “people we call carbohydrate cravers,” says Wurtman. Serotonin-depleting diets can make them irritable, “yearning to eat something sweet or starchy. When you take away carbohydrates, it’s like taking away water from someone hiking in the desert.”

Michaels Pouls of Gladwyne, Pennsylvania, remembers those feelings all too well. “I can recall being on Atkins and craving fruit – I needed the sugar in fruit, but you can’t have any fruit on Atkins. I wanted salad – I was dying for salad.

”Two years ago, Mr. Pouls came to the Pritikin Longevity Center and found that “with Pritikin, I can have just about everything I desire. It satisfies all my food cravings.” He has since lost 78 pounds. “I’ve gone from a size 44 to a size 34 waist. I have this belt that I love, and I’ve had to put two extra holes in it to keep wearing it – that’s a good problem to have!”

He’s much happier in other ways, too. Gone are the cravings and grumpiness brought on by highprotein dieting.

“EMOTIONAL ZOMBIE”

Fatty foods like bacon or cheese are not good for the psyche, either. “They’ll make you tired, lethargic, and apathetic,” cautions Wurtman. “Eating a lot of fat will make you an emotional zombie.”

Other studies have confirmed the positive emotional effects of a diet full of natural, fiber-rich carbohydrates. In a recent survey of 200 people in Great Britain, called the Food and Mood Project, 88% reported that changing their diet improved their mental health significantly. The foods most likely to alleviate mood swings, anxiety, and depression were fruits and vegetables. Eating regularly and not skipping breakfast also boosted mental health. Food “stressors” – those foods that negatively affected mood – included sugar, caffeine, and foods rich in saturated fat, such as meat, chocolate, and full-fat dairy products. (To download The Food and Mood Project Survey, go to www.foodandmood.org.)

It’s important, recommends Dr. Wurtman, to follow an eating plan, like Pritikin, that is largely carbohydrates. “The only way the brain makes serotonin is when carbs are eaten with little or no protein.” So a meal like pasta primavera and a large salad will allow the brain to produce serotonin, but one like pasta and a large serving of chicken won’t.

“The Pritikin Program is an excellent and healthy program,” asserts Dr. Wurtman, “and would probably be very effective in maintaining serotonin levels and mood.”

IMMEDIATE BENEFITS

The good news, too, is that for many people starting the Pritikin Program, mood improvements happen almost immediately, often within a month. “After just three weeks of following Pritikin, my moods and outlook on life improved dramatically. I’ve now been following Pritikin for four months, and my mental health has never been better,” says Kim Horrell of Little Rock, Arkansas.

“I am happier and far more motivated to get out of the house every morning and exercise, which I could never do before. And for the last few weeks, I’ve been deep-cleaning my house, and it’s 6,000 square feet, so it’s quite a job! I have more energy than I’ve ever had in my entire life! Plus, I’ve gone from size 14 jeans that fit tight to 8 jeans that fit and look great.

“I’m healthy, happy, and thin. Wow!”

* British Journal of Psychiatry, 2000; 176: 72.
Psychological Medicine, 2003; 33: 1381.