Foods that may increase serotonin levels naturally include eggs, salmon, cheese, tofu and turkey, says Healthline. These foods have high tryptophan levels, and eating them with carbohydrate-rich foods, such as bread, pasta or rice, may assist the absorption of tryptophan into the brain, which increases serotonin levels.
Tryptophan is an amino acid that is responsible for the synthesis of serotonin in the brain, explains Healthline. Tryptophan from food does not cross the blood-brain barrier easily due to competition from other amino acids in the blood, preventing its beneficial effect on serotonin levels. However, with the addition of carbohydrates to a tryptophan-rich meal, the resultant increase in insulin causes higher absorption of these other amino acids into the heart, muscle tissues and body organs.This leaves fewer competing amino acids in the blood and increases the likelihood of successful tryptophan absorption into the brain.
Other natural ways to increase serotonin levels include regular exercise, which research shows has antidepressant effects; and increased exposure to sunshine or other bright light, which causes serotonin levels to rise and is especially helpful for seasonal depression, suggests Healthline. Research also shows that having a positive attitude towards life during daily activities and engaging in frequent social interaction can lead to a significant increase in serotonin levels.