|MadSci Network: General Biology|
Aloha, Autumn, My apologies for taking so long in answering this question. During summer, I'm not always in my office. Also, I needed some help in answering this question, since it has several pieces to it, as you will see. Dr. Alan Titchenal, who also teaches introductory nutrition with me, helped me think through some of the answer. First off, I'm not sure if you meant to ask about 'melanin' or 'melatonin'...so I will discuss both. According to my medical dictionary, melanin is the dark pigment of the hair, skin, the covering of the eye, and a part of the brain (substantia nigra..'nigra' meaning 'black'). Melanin can also be found in some tumors (like dark moles on the skin). It is made in the body from a portion of protein (the amino acid tyrosine)...so for your body to make the correct amount of melanin, you simply need to have adequate protein in your diet. Fruits contain very little protein. Good sources of protein include meat, fish, milk/milk products, eggs. Protein is also found in varying amounts in grain food(bread, pasta, rice, noodles, etc.). Your body is programmed via your genes (your inheritance from your biologic parents) to produce a certain amount of melanin...that is why we all have different colors to our skin. People who have darker skin simply have more melanin produced in their skins that do people with lighter skins...and melanin does offer some protection from the damage that certain UV-wave lenghts in sunlight can cause. Thus a darker-skinned person has more sun-protection than a fairer-skinned person. As an aside, I don't think you can regulate the amount of melanin that your body produces...unless you modify your genetic make-up somehow...and scientifically we aren't there yet. The reason that I think you might have meant 'melatonin' is that it sounds like 'melanin'..and melatonin is in the news a bit, related to its use as a sleep-aid supplement. Melatonin is also made in your body from a piece of protein (the amino acid tryptophan). Most of the melatonin in your body is found in the pineal gland, which is in the upper part of the brain, just under the skull. Melatonin is a hormone that plays a role in sleep regulation...and people have used melatonin supplements to modify their sleep-wake cycles, with varying degrees of success/failure. There is an excellent website about sleep/melatonin (www.sleepfoundation.org)if you're interested. There is only one direct food source of melatonin that I've been able to find: tart cherries. I have no idea why it is found in cherries?! The melatonin in supplements is extracted from BEEF pineal glands. With all the current discussion about mad cow disease, I'm not sure if taking these supplements is a wise choice, since the prion (disease- causing particle) that seems to be the cause of a mad-cow-like disease in humans (varient Creutzfeld-Jakob disease, vCJD) is found in the brain/spinal cord of infected cattle. I don't think that eating beef grown/raised in the US is a danger (yes, I eat beef, myself), since we have had no cases of vCJD caused by any beef eaten here...and I don't think we will. However, it has been a problem in England over the last decade. Anyway, if you were interested in melatonin, rather than melanin...there are a number of things to consider: the source of the supplement, the reason for taking it, and the amoung that you would be taking. Melanin? Melatonin? Either one: they are made from portions of the protein in your food. If you are getting enough of a variety of protein foods, you are able to make plenty of either. Also, unless you take large amounts (like melatonin) as supplements, you probably can't change the amount of either in your body. Especially for melanin, since the amount of that is tightly controlled by your genes.
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