|MadSci Network: General Biology|
Hello, from Idaho. They say the eyes are the window of the soul. Doctors can tell a lot when looking into the eyes of their patients. A whole pseudoscience has developed around this practice, called iridology, the study of the iris as associated with disease. Dr. Stephen Barret, who runs an excellent web site on www.quackwatch.com, has called iridology a dubious practice. Color changes in the iris begins after birth. For example, most Caucasian babies have blue eyes and begin to darken as they age, whereby their true color usually sets in by 6 months. Afro-Americans and some other darker skinned peoples are born with brown eyes and their eyes remain brown for life. The pigment in the eyes are due to cells known as melanocytes, and heredity determines one's eye color. The more melanin, the darker the color. When these cells are deeper in the eye, the color produced is blue or green, resulting from the way lightwaves are scattered by the melanocytes. When they are closer to the surface, the eye is brown. Albinos have eyes that appear pink, because the melanocytes which ordinarily masks blood vessels, are lacking. The reason you've never noted any contrary evidence to the claim that eating raw food causes the eyes to change color is because this doesn't happen. If there were such a link, scientists and the general population would have noticed this connection by now. There is no scientific evidence that eating any type of diet, raw or otherwise, will change one's eye color. A quick perusal of the web quickly elucidates where this claim is coming from. Practitioners of iridology, naturopathy and 'New Age', are just a few. There are many claims and anecdotes that's made by members of such groups, however, they are hard pressed to prove these claims when measured against rigorous scientific studies. Many foods are eaten raw, such as fruits, nuts and vegetables. The Japanese culture eats many raw foods, such as sushi. There are those who like steak tartare, or savor eating raw oysters, clams or other mollusks, while others prefer drinking 'raw' milk or downing raw eggs. The problem with eating raw foods, in general, is a significantly higher risk of food poisoning from bacteria, which otherwise would be killed by cooking. Cooking helps break down fiber, carbohydrates and protein, making for easier digestion and release. It increases the nutritive value of foods, making them more bioavailable, such as in carrots, spinach and tomatoes, by releasing greater amounts of carotenoids. It makes food edible that would otherwise be inedible or unpalatable. It brings out the aroma and flavor of food, enhancing appetite and contributes to the pleasure of eating. Although cooking, and especially overcooking, has its drawbacks, its benefits outweigh the risks. In short, cooking improves one's health. Indeed, the late Carleton Coon, an American anthropologist and leading authority on the peoples and cultures of North Africa and the Middle East wrote, that cooking was "the decisive factor in leading man from a primarily animal existence into one that was more fully human." Be careful when reading from the web, and try to search out scientifically based organizations for more accurate information. I strongly recommend, - www.quackwatch.com Hope that helps, Peter Bosani. References: The Family Health and Medical Guide - Publisher - Doubleday Food in History - Author - Tannahill Food and Nutrition- Life Science Library
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