5-Hydroxyindoleacetate

High levels of 5-hydroxyindoleacetate may occur if there are inherited high-activity enzyme variations on the breakdown pathway or if there are higher levels of its precursor serotonin. A higher rate of serotonin breakdown may decrease serotonin levels while 5-hydroxyindoleacetate levels remain high.

- Low levels of serotonin have been associated with obsessive-compulsive disorder (OCD), aggression, insomnia, fibromyalgia, rheumatoid arthritis and depression. Eating disorders and migraine headaches may also be related to low serotonin levels. If appropriate, consider slowing serotonin breakdown with selenium and antioxidant support. Antioxidant supports may include CoQ10, alpha-lipoic acid, vitamins C and E, curcumin, resveratrol, etc. Fresh fruits and vegetables are rich in antioxidant compounds. Increased levels of methylmalonate, quinolinate and pyroglutamate, with decreased levels of cis-aconitate and isocitrate, can indicate poor antioxidant status. If appropriate, consider supporting serotonin synthesis with vitamin B6, D, iron (if deficient) and tetrahydrobiopterin (BH4). Tryptophan or 5-hydroxytryptophan (5-HTP) may be used to supply substrate and tryptophan may be given on an empty stomach to increase absorption and decrease transporter competition by other amino acids.

- High levels of serotonin in the central nervous system may result in cognitive changes/confusion, restlessness, headaches, GI hypermotility, tachycardia, agitation, and may contribute to schizophrenia. Diets high in simple carbohydrates may increase serotonin levels. The use of tryptophan or 5-HTP supplements, insulin and certain medications may also increase serotonin levels. High serotonin levels may also occur if there is an enzymatic block in melatonin synthesis. If appropriate, consider supporting serotonin breakdown with vitamins B2, B3, iron (if deficient), and molybdenum. If insomnia or sleep disorders are present, consider melatonin supplementation.

Low levels of 5-hydroxyindolacetate may occur if there are nutritional enzyme inhibitions or inherited low-activity enzyme variants present in the breakdown pathway, or if there are low levels of its precursor serotonin. Serotonin is derived from the essential amino acid tryptophan and is essential for normal neurotransmission in the central nervous system and the gastrointestinal (enteric) nervous system. Serotonin also regulates the dilation and constriction of blood vessels and plays a role in immune system and bone health. The breakdown of peripheral serotonin occurs primarily in the liver; low levels of 5-hydroxyindolacetate and vanilmandelate may indicate the presence of a liver disorder. Support either serotonin synthesis or breakdown depending upon symptoms.

1. Low levels of serotonin have been associated with obsessive-compulsive disorder (OCD), aggression, insomnia, fibromyalgia, rheumatoid arthritis, and depression. Eating disorders and migraine headaches may also be related to low serotonin levels. If appropriate, consider supporting serotonin synthesis with vitamin B6, D, iron (if deficient) and tetrahydrobiopterin (BH4). Tryptophan or 5-hydroxytryptophan (5-HTP) may be used to supply substrate, and tryptophan may be given on an empty stomach to increase absorption and decrease transporter competition by other amino acids. Digestive disorders may decrease tryptophan absorption. Consider a US BIOTEK VITAMIN D PROFILE (serum or dried bloodspot).

2. High levels of serotonin in the central nervous system may result in cognitive changes/confusion, restlessness, headaches, GI hypermotility, tachycardia, agitation, and may contribute to schizophrenia. Diets high in simple carbohydrates may increase serotonin levels. The use of tryptophan or 5-HTP supplements, insulin and certain medications may also increase serotonin levels. High serotonin levels may occur if there is an enzymatic block in melatonin synthesis. If appropriate, consider supporting serotonin breakdown with vitamins B2, B3, iron (if deficient), and molybdenum. If insomnia or sleep disorders are present, consider melatonin supplementation.

5-Hydroxyindoleacetic acid (5HIAA) is a breakdown product of serotonin that is excreted in the urine. Serotonin is a hormone found at high levels in many body tissues. Serotonin and 5HIAA are produced in excess amounts by carcinoid tumors, and levels of these substances may be measured in the urine to test for carcinoid tumors.