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Review Article: L-Tryptophan and 5-Hydroxytryptophan (5-HTP)

Initial Posting: 9/12/10  Updated: 8/2/2013 Review Article on L-Tryptophan and 5-HTP

Choosing the Best L-Tryptophan and 5-Hydroxytryptophan Supplements

L-Tryptophan Supplements Are Back -- But Are They Safe?  And Do They Work?

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 L-Tryptophan and 5-HTP

L-Tryptophan hurt many people in the 1980s.  It's available once again.  Should you use L-tryptophan? Find out the pros and cons.  Isn't your health worth it?
L-Tryptophan was a popular sleep aid in the 1980s until over 1,500 people became ill, several dozen died, and L-tryptophan was removed from the market as an over-the-counter product.

L-Tryptophan has made a comeback in recent years and is widely available again. Why? Are the supplements safer than before? Do risks for L-tryptophan remain? provides answers to these and other important questions about L-tryptophan, its effects, and potential side-effects. 

5-HTP, a related supplement with different uses, including a role in treating depression, is also reviewed -- along with potential risks. Due to the difficulty of testing these products for potential impurities (as discussed in the report) did not analyze specific brands of L-tryptophan or 5-HTP.

You must be a member to get the report on L-tryptophan and 5-HTP. In this comprehensive review article, you'll discover:
    • The evidence for and against L-tryptophan and/or 5-HTP for sleep, depression, anxiety, smoking cessation, migraine headache, and weight loss.
    • Dosage for specific uses.
    • Problems caused by L-tryptophan supplements in the past and more recently, what may have caused them, and concerns that remain.
    • Who should be particularly cautious about using L-tryptophan or 5-HTP supplements. 
    • Side-effects and potential drug interactions of L-tryptophan and 5-HTP supplements.
    • Good food sources of L-tryptophan.

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Learn More About L-Tryptophan and 5-Hydroxytryptophan Supplements Answers -- for L-Tryptophan and 5-Hydroxytryptophan (5-HTP)
I take fluoxetine (Prozac), a SSRI drug to treat depression. Are there supplements I should avoid, or be taking, due to this drug? Get the answer >>

Do any supplements help with migraines? Get the answer >>

Which supplements can cause diarrhea? Get the answer >>
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