Serotonin & Weight Loss

Serotonin is a hormone made in the body from the amino acid tryptophan. It is used by the nervous system to help regulate appetite, bowel and bladder function, sleep cycles and moods. Lower levels of serotonin are associated with depression, insomnia and weight gain. Certain medications and supplements can increase serotonin levels, and have been used to control appetite and aid in weight loss. Always consult your physician before using such supplements to lose weight.

The Weight-Gain Problem

While poor diet and a sedentary lifestyle are obvious contributors to weight gain, other factors such as hormone imbalance, depression and irregular sleep patterns can also compound the problem. Serotonin is such a widely used chemical in the body that a lack of it can lead to a number of other problems associated with weight gain, such as weakness or fatigue, depression and difficulty sleeping. Weight gain is also a common side effect reported by those taking SSRIs, or selective serotonin reuptake inhibitors, for depression. Talk with your doctor if you have experienced sudden weight gain or weight gain while taking prescription medication.

The Serotonin Solution

Because low serotonin levels appear to be a common denominator in several issues connected to weight gain, many experts now focus on treating the root of the problem chemically. OB/GYN nurse practitioner Marcelle Pick explains that when serotonin levels are down, we tend to crave more carbohydrates or sweets. Those sweet cravings can not only indicate a problem, but over indulging in sweets can also lead to more weight gain. The key may be to help the body increase serotonin levels naturally, which in turn will help control appetite, improve mood and lead to weight loss.

Sources of Serotonin

Serotonin must be made by the body. However, there are ways to help the body increase production of serotonin. 5-HTP, a popular supplement derived from the African plant Griffonia simplicifolia, promotes serotonin production. It is used by herbalists to treat depression, insomnia, migraines and weight gain. As 5-HTP is still being investigated, check with your doctor before trying this supplement.

Serotonin production is also increased by certain nutrients in the diet. B vitamins found in whole grains and legumes help the body convert the hormone tryptophan into serotonin. Tryptophan-rich foods include turkey, salmon, tuna and dairy products. Outside of diet, regular exposure to direct sunlight also stimulates serotonin production.


Although serotonin is essential in maintaining a healthy weight, it is not the only factor. Any weight loss plan should include following a healthy diet and exercise program. Rather than sticking to a fad diet with a limited menu or harsh restrictions, try simply following the dietary recommendations outlined in the USDA Food Pyramid. Eat a variety of foods, including whole grains, fresh fruits and vegetables as well as lean meats. Additionally, the National Institutes of Health points out that regular exercise may also increase levels of serotonin in the brain. The USDA suggests at least a half hour of moderate to vigorous exercise each day.