By Mila McManus MD
Global markets for collagen supplements have grown by double digits for the last three years. Collagen supplementation is all the rage for bones and joints, skin, hair, nails, and gut health. But are there any drawbacks to collagen supplementation?
Multiple studies are suggesting that those who experience symptoms such as anxiety, irritability, low self-esteem, poor sleep, and depression may want to avoid or limit collagen supplementation. Why? Collagen is an incomplete protein and requires another amino acid called tryptophan, in order to be properly utilized in the body. When the supplement is taken, the body has to give tryptophan to the absorption process of collagen, thus robbing the body of tryptophan stores. Thus, taking a collagen supplement can induce tryptophan depletion. This is problematic because tryptophan is a precursor to a neurotransmitter called serotonin. Many who struggle with anxiety or depression, for example, already lack adequate levels of serotonin. If there is not adequate tryptophan available in the body to make serotonin, moods will likely suffer. Serotonin is important and helps us to be calm, contend with stress, sleep well, feel optimistic and hopeful. Low levels of serotonin are associated with anxiety, irritability, eating disorders, OCD, PTSD, poor sleep quality, and insomnia. If you have any of these symptoms and are taking a collagen supplement, consider stopping it for a couple of months to see if your symptoms improve. If collagen supplementation is important to you, consider adding a supplement called 5-htp (5-hydroxy-tryptophan) which provides the body with more of the building block to make serotonin. (5-htp is over-the-counter and should be taken under medical supervision)
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