Summary

Although L-tryptophan and 5-HTP are both known as building blocks of serotonin, there are important differences between the two nutrients. biochemically, 5-HTP is only a stepping-stone between L-tryptophan and serotonin. It has no other function in the body but to produce serotonin.

The value of 5-HTP stems from the fact that it is the last step before serotonin. When you take 5-HTP, it converts more efficiently and produces more serotonin, pound-for-pound, than L-tryptophan.

There are two reasons for this. Between L-tryptophan and 5-HTP is an enzyme that controls how much L-tryptophan passes through to serotonin. This enzyme acts like a faucet, adjusting your serotonin levels moment to moment.

5-HTP, on the other hand, bypasses this “rate-limiting” step, boosting your serotonin levels without much control. Some people need this because the enzymatic faucet that allows L-tryptophan to change into 5-HTP is too limiting. People with this condition are lucky that 5-HTP is available.

The second difference is that L-tryptophan plays an extraordinary number of roles in your body. After all, it is an essential amino acid, and 5-HTP is not. Only a small percent of L-tryptophan turns into serotonin, while most of the rest goes into a vast array of proteins, including enzymes that are crucial for life.

Research confirms the fact that L-tryptophan is our most limiting, essential amino acid, so a deficiency in our country may be commonplace. Given the avalanche of serotonergic drugs being sold every day, this may not be far-fetched. The fact is, if you have an L-tryptophan deficiency, there really is no other option than to increase your L-tryptophan intake, either through your diet or through supplements.