What we eat, drink affects our brain chemistry

During stressful times, some people report a marked increase in appetite, giving way to cravings and bingeing. This can be due, in part, to hormone fluctuations and tied into what is known as the “fight or flight” response.

Having information on how what we eat and drink affects our brain chemistry can help us make more rational and healthy decisions. Interestingly, factors such as meal size and circadian rhythms can also affect eating patterns, alertness and performance. For example, consuming a lunch meal of 1,000 calories has been associated with a decrease in performance during the afternoon. Meals that are high in calories tend to be higher in fat, and fat slows down the absorption of food. The result is an increase of blood flow to the stomach for a longer period of time, while blood flow to the brain decreases, resulting in a sleepy or sluggish feeling.

Circadian rhythms occur throughout the day, and influence our energy levels. “Morning people” feel more energetic and focused earlier in the day. Because their energy levels begin to drop during the afternoon and evening, they do well with protein-rich foods during this time. Doing so boosts levels of dopamine and norepinephrine, brain chemicals that produce increased concentration and reaction times. For “night owls” it is important to include a protein-rich food as part of breakfast and midmorning snack. Protein provides the brain with tyrosine, a precursor of the chemicals that promote alertness. High quality protein can be found in both animal and plant sources.

What about those pesky cravings? Between 3 and 4 o’clock in the afternoon many people experience carbohydrate cravings due to serotonin levels dropping. Research shows that women have less brain serotonin than men, and that a serotonin-depleting diet such as a high protein/low carb eating plan is more likely to make them feel irritable. Carb cravers may notice they don’t feel their best in the late afternoon or mid-evening and often find that eating carbohydrates helps keep their moods steady. This isn’t just a matter of willpower or mind over matter, rather, the brain sends out signals to eat carbohydrates. Clinical studies have shown that if the carbohydrate craver eats protein instead, he or she is more likely to feel grumpy, irritable or restless, while filling up on fatty foods like bacon or cheese contributes to tired, lethargic and apathetic moods.

Along with a calming affect, the brain chemical serotonin is also an appetite suppressant. The brain makes serotonin after a person consumes sweet or starchy carbohydrates. To have this effect, research has determined that these carbohydrates must be eaten with very little or no protein.

The more we know about our habits around food, the more empowered we can be to choose wisely.

The bulk of any diet should be healthy, but an occasional treat can also have a place in your eating plan.