Eat some foods that contain tryptophan. Tryptophan helps your brain produce chemicals that improve mood and have a relaxing effect. Milk, bananas, oats, soy, poultry, cheese, nuts, peanut butter and sesame seeds are good sources of tryptophan.

Eat frequent small meals. This will help stabilize your blood sugar throughout the day.

Increase your intake of carbohydrates (starches). Carbohydrate-rich meals and snacks are thought to increase the amount of serotonin in your brain, which has a calming effect. Eat foods rich in complex carbohydrates (such as whole grains), and eat fewer simple carbohydrates (sugars).

Drink plenty of water. Even mild dehydration can affect your mood.

Limit or avoid alcohol. The immediate effect of alcohol may be calming for most people. But as alcohol is metabolized by your body, it can cause anxiety-like symptoms.

Limit or avoid caffeine. Caffeine is a stimulant that can make you feel jittery and nervous and interfere with sleep.

Pay attention to food sensitivities. In some people, certain foods or food additives can cause adverse reactions, including moodiness — which can lead to irritability or anxiety. Foods that commonly cause reactions include wheat, corn, soy, dairy, eggs, nuts and shellfish.