You Are, Indeed, What You Eat

That old maxim just might be right: The way to the heart may be through the stomach.

Breads and other carbohydrate-rich foods could bring on a smile, while protein-filled fish and meat may help you ace that exam, according to research suggesting that what we eat changes how we think and feel.

"You can manipulate your mood and your mental acuity just by what you eat and when, and the effects can happen very quickly," says Dr. Judith Wurtman, a research scientist at the Massachusetts Institute of Technology (MIT), and author of Managing Your Mind and Mood Through Food.

She and her husband, Dr. Richard Wurtman (also of MIT), have studied the food-mood connection for the past 30 years.

Carbohydrates and Protein Have Roles

According to Dr. Judith Wurtman, the news that carbohydrates can lift the spirits first emerged about a dozen years ago, in studies she conducted with women suffering from premenstrual syndrome.

"Eating carbohydrates had a profound and dramatic effect in improving mood," notes Dr. Wurtman. "I'm talking about anger, irritability, depression, difficulty concentrating, mental fuzziness. We found that you could reverse those mood changes with carbohydrate-rich foods, in about 30 minutes."

Carbs can do little to change serious clinical depression, but they do seem to help battle the everyday "blahs," she says.

The reason may be very simple, she notes: the body uses carbohydrates to manufacture serotonin - the key emotion regulator in the brain.

"When you eat carbohydrates and make more serotonin, mood disturbances that you may have been suffering can go away, at least temporarily," says Dr. Wurtman.

There is one caveat, though: Eating a fatty food along with the carbs slows down digestion and inhibits this feel-good response.

"So, if you really want to feel better, try carbohydrates but try something like a fat-free breakfast cereal, rather than a slice of bread slathered with [fatty] peanut butter," advises Dr. Wurtman.

And what about protein? Dr. Wurtman says the science on that is a little sketchier.

"My husband discovered years ago, however, that one of the amino acids in protein, called tyrosine, does increase the synthesis of two key chemicals in the brain, norepinephrine and dopamine, which we call the 'mental alertness' chemicals," she says.

For this reason, Dr. Wurtman recommends protein-heavy diets for people facing extended periods of mental strain, such as preparing for an important exam. "It'll help you replenish those chemicals in your brain," she says.

The researcher says myths abound when it comes to specific foods and their effect on emotions. The number one myth: the sugar "high."

Far from making kids rambunctious, sweet treats are more likely to send them snoozing, says Dr. Wurtman.

"In studies done in the 1980s, a National Institutes of Health [NIH] researcher, Judith Rapaport, gave kids Kool-Aid® sweetened either with sugar or aspartame. A half-hour later, the kids that had had the sugar were found slumped in a corner, dozing," she says.

Another myth circulates every Thanksgiving - snooze-inducing, tryptophan-laden turkey.

Again, tryptophan itself does not make you sleepy. According to Dr. Wurtman, tryptophan is an amino acid, a molecule that is part of protein.

However, it is found in exceedingly small quantities and has to compete with other, more abundant amino acids to make it into the brain. It is a race tryptophan usually loses, she said.

"However, when you eat carbohydrates, insulin is released," notes Dr. Wurtman.

Insulin works to push all protein amino acids except tryptophan into the muscles and away from the brain. The result? Tryptophan finally gains access to brain tissue.

So, by itself, gorging on Thanksgiving turkey (or any other protein-rich food) should not make a person sleepy.

"But when you eat the stuffing, the pecan pie, the butter, gravy and wine - then you get sleepy," explains Dr. Wurtman.

Overdoing Fats Linked to Self Esteem

And fats? So far, science has not proven they affect short-term mood. However, high-fat diets may have longer-term consequences on mental state.

"If you're obese and your health isn't so great, your mood isn't so great, either," she says. And she notes that, in her work with the very obese, she has often noticed that many say they eat "to 'get drunk' on food - that's what I've been told.

"Sometimes people will eat high-fat foods and fall into a kind of mental stupor, almost an emotional coma," she says.

Food can have much more constructive emotional effects, however. Dr. Wurtman believes most people unconsciously know this, anyway.

"When people are upset, they tend to reach for foods to make them feel better," she says. The key, according to Dr. Wurtman, is choosing those foods wisely.

Always consult your physician for more information.