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Tryptophan & Niacin

author image Joseph Pritchard
Joseph Pritchard graduated from Our Lady of Fatima Medical School with a medical degree. He has spent almost a decade studying humanity. Dr. Pritchard writes as a San Francisco biology expert for a prominent website and thoroughly enjoys sharing the knowledge he has accumulated.
Tryptophan & Niacin
Grilled chicken with grilled vegetables Photo Credit: ALLEKO/iStock/Getty Images

Your body needs essential nutrients in regular amounts in order to continue to function properly. Of these, the amino acid tryptophan and the vitamin niacin share a special link. These two nutrients have different properties and fulfill very specific roles in your body’s biochemical processes. In addition, a deficiency in either one of these chemicals can lead to negative health effects.

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Tryptophan Defined

Tryptophan is an essential amino acid, meaning that your body cannot produce it, and it must be obtained from food sources, the University of Maryland Medical Center explains. It is important for ensuring the proper growth of infants and maintaining nitrogen balance in adults. Your body also uses tryptophan to manufacture niacin, a B vitamin, and serotonin, a neurotransmitter. Serotonin plays a role in regulating sleep and moods, and in controlling impulses in the brain. A severe deficiency in tryptophan can lead to insomnia, depression, anxiety, irritability and unexpected weight loss or gain.

Niacin Defined

Niacin is an organic compound and one of the eight B vitamins. Also known as vitamin B-3, it is water-soluble, meaning that it dissolves in water and excess amounts leave your body through your urine. This means that you need a regular supply of niacin in your diet, MedlinePlus notes. Your body uses niacin as a critical component of its digestive process, as it breaks down carbohydrates, fats, proteins and alcohol and converts them into usable energy.

The Link Between Tryptophan and Niacin

Your liver uses tryptophan, in conjunction with enzymes containing vitamin B-6 and iron, to produce niacin. On average, 60 mg of tryptophan yields around 1 mg of niacin, the Linus Pauling Institute explains. In addition, insufficient dietary intake of either niacin or tryptophan can result in pellagra. Symptoms of this disease include delusions, diarrhea, vomiting, mental confusion, depression, memory loss, scaly skin sores, and inflamed mucus membranes. If left untreated, pellagra can result in death.

Recommended Dosage

The optimal dosages for niacin are based on the recommendations of the Institute of Medicine and vary depending on your age and gender, MedlinePlus Medical Encyclopedia notes. Males above 14 years of age should get 16 mg per day, while females of the same age should get 14 mg daily. Pregnant or lactating women need larger amounts.

You do not need to take tryptophan supplements unless you have health issues that require it, such as insomnia. Eating a balanced and healthy diet is usually enough to meet your body’s daily requirements for this amino acid. In addition, not all uses of tryptophan supplements have been approved by the Food and Drug Administration, reports. Therefore, you should never take any supplements without consulting your doctor first.

Food Sources

Tryptophan can be found in cheese, chicken, turkey, eggs, fish, milk, nuts, peanuts, pumpkin seeds, sesame seeds, soy products and tofu. Meanwhile, niacin is found in poultry, fish, lean meats, nuts, eggs and dairy products. Many legumes, enriched breads and cereals also provide a smaller amount of niacin.

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