N-Acetyl-L-tyrosine is showing up in spam emails and on twitter so I had to take a look to find out what claims are being made for it. I suspected that marketers might be calling it a panacea, and I was right. At least one website (which mentions, hilariously, FDA censorship on this) lists several diseases, disorders and conditions, that the compound (a metabolic precursor of tyrosine) might help with. Although they don’t say specifically that it’s the N-acetyl-L-tyrosine functioning medically but allude to its putative activity on the basis that tyrosine itself supposedly has these activities.

They claim that the compound is a precursor for the neurotransmitters dopamine and norepinephrine, a precursor for the pigment compounds melanins, and for the thyroid hormones (e.g. thyroxin). Lifelink, for instance, makes the bold statement:

Most of the medical research relating to tyrosine supplementation has been conducted using L-tyrosine itself, not acetyl-L-tyrosine. It is logical to assume, however, that the conclusions reached will apply to acetyl-L-tyrosine as well, since the latter is converted to L-tyrosine in the body. The following discussion therefore draws from studies of L-tyrosine.

By implication then N-acetyl-L-tyrosine can purportedly be used in treating mood problems and depression, hair and skin colour, blood pressure, and Parkinson’s disease!

If you were offered a drug by your physician to improve your hair colour but the doc then pointed out that it might affect your brain and your blood pressure, wouldn’t you be worried? Indeed, the pharmaceutical industry spends billions of dollars trying to eliminate side effects and focus the specificity of its products to avoid such issues as multiple activities of any given drug.

Several of the references given to support the use of N-acetyl-L-tyrosine are nothing more than Wikipedia entries. I don’t want wiki entries when I’m assessing a medical effect, it’s not that Wiki is not credible, but how can the lay reader be sure that what they’re reading on there is valid, it may have been edited to promote the compound by someone with a vested interest or a conflict of interest.

Give me large-scale, randomized, double-blind, placebo-controlled, clinical trials every time and you’ll convince me. Spurious musings on possible benefits are not medical evidence.

Also of note are the physical properties of N-acetyl-L-tyrosine listed by ChemSpider:

CAUTION: May irritate eyes, skin, and respiratory tract

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  1. F the FDA

    this article on the FDA and Gov’t suppressing information on helpful natural products is true….the FDA does not want americans to know that there are natural substances that work and in most cases better then the drugs!!!!!!!!!!! not to state the drug companies spend millions of dollars to limit side effects is staight up BULLSH*T!!! 90% of the medication do not work !!! and if you do any research N-acetyl-tryrosine boosts mood, regulates blood pressure etc etc etc do not beleive the FDA is out to help you…they are only concerned with their own pockets and the pockets of their shair holders THATs IT!! infact if they where at all concened about our health they would have released the cure for cancer and many other diseases…do some research got god sakes …the best Doctor in the world is you..you know your body the best!!!! do your homework you would be shocked to see what you find….

  2. David Bradley

    Such a well reasoned and beautifully written argument…not.

  3. Bob Macklin

    @David, your arguments are weak! The pharmaceuticals spend millions of dollars trying to eliminate the side-effects of their drugs? NOT! They spend the majority of their money on sales and marketing, otherwise known as drug pushing. Comparatively, a much smaller amount of money goes into actual research. Most of their block-buster drugs are just patentable, chemical alterations of natural medicinal compounds discovered and used by “primitive” societies. Other drugs are just old ones with new uses. Guanfacine is a new ADHD drug that is actually an old hypertensive medication. In addition, they also receive tons of money directly and indirectly from government to research new drugs.

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