Guest guest Posted March 9, 2005 Report Share Posted March 9, 2005 " HSI - Jenny Thompson " <HSIResearch HSI e-Alert - Pumping Sunshine Tue, 08 Mar 2005 11:56:40 -0500 HSI e-Alert - Pumping Sunshine Health Sciences Institute e-Alert **************************************************** March 08, 2005 **************************************************** Dear Reader, Men who develop prostate cancer are usually diagnosed with the disease after the age of 70. This is exactly the time in their lives when vitamin D levels tend to be lowest. In addition, the dark skin pigment called melanin blocks ultraviolet light, which the body uses to produce vitamin D. And black men (who tend to have high levels of melanin) have a higher risk of prostate cancer than men with lighter pigmented skin. So could there be a connection between vitamin D deficiency and prostate cancer risk? According to a new study from Brigham and Women's Hospital and Harvard University School of Public Health (BWHU), that association is significant and may provide an important tool in preventing this cancer and in treating cases in which the disease is aggressive. But what's the best way for men to maintain adequate levels of vitamin D? Ah, there's the rub. Because you'll find quite a bit of vitamin D advice out there that ranges from misguided to just plain wrong. ----------- Calming the aggressive ----------- The BWHU team used blood samples taken from 2,400 men who had participated in the Physician's Health Study. During a 13-year follow up period, a little more than 1,000 of the subjects developed prostate cancer after the samples were taken, while more than 1,300 remained free of the cancer. Researchers measured blood plasma levels of vitamin D, and also analyzed variations in the vitamin D receptor (VDR) gene and its possible link to prostate cancer risk. The VDR gene determines how well vitamin D is utilized by the body. Analysis of the data produced two striking results: 1) Subjects who had the highest vitamin D levels cut their prostate cancer risk by nearly half, compared to subjects with the lowest D levels 2) Subjects who had a specific genotype that facilitates the benefits of vitamin D, and who also had high levels of D, were estimated to have a 55 percent lower risk of developing prostate cancer, and more than 75 percent lower risk of developing an aggressive form of the cancer The researchers believe that their study is the first to confirm that vitamin D offers protection against prostate cancer, as well as a tendency to curb clinically aggressive forms of the disease. ----------- Where did those shoes go? ----------- A NutraIngredients.com report on the BWHU study featured comments from a UK nutritionist who stated that the best way to get vitamin D is by eating fortified cereals. Regular e-Alert readers won't be surprised that I nearly jumped out of my shoes when I read that one. As I've noted in previous e-Alerts, the best dietary sources of vitamin D are eggs, liver, fish liver oils, and oily fish such as salmon, sardines, trout, and tuna. But by far, the best source of vitamin D is through sun exposure. When your skin is exposed to ultraviolet light, your body responds by manufacturing vitamin D. Of course, the idea of sun exposure runs against the current popular " wisdom " that you should completely avoid sunlight unless covered scalp to ankles with sunblock. But as Dr. Jonathan V. Wright, M.D., has pointed out in his Nutrition & Healing newsletter, sun exposure is not only good, it's essential. The damage that can set the stage for skin cancer comes when exposure is extreme and results in sunburned skin. Unfortunately, the amount of sun needed to prompt the body to create vitamin D is only available in most of the U.S. during the summer months. For the remainder of the year - and for those who live in extreme northern and southern latitudes - the most accessible source of vitamin D is from fish oil supplements. ----------- Measuring up ----------- Older men and black men should ask their doctors to check their vitamin D levels by monitoring blood tests for 25-hydroxyvitamin D (also known as 25(OH)D). This is the best way to be certain that they're getting enough vitamin D. According to natural physician Dr. Joseph Mercola, the optimal 25(OH)D value is 115-128 millimicromolar (nmol/L). A value below 50 is considered a serious deficiency that increases the risk of chronic diseases, including breast cancer. By some estimates, as much as 40 percent of the population is vitamin D deficient, with a relatively small percentage qualifying in the optimal 25(OH)D range. In a 1999 issue of the American Journal of Clinical Nutrition, Reinhold Vieth, M.D., of the University of Toronto laid out some guidelines for supplementing above the vitamin D recommended dietary allowance of 200 IU per day. Dr. Vieth wrote that in order for 25(OH)D to exceed 100 nmol/L, a daily vitamin D intake of 4,000 IU is necessary. And Dr. Vieth notes that, except for people who have a hypersensitivity to vitamin D, there are no adverse effects with 25(OH)D levels under 140 nmol/L. But to reach that upper level you'd need to take 10,000 IU per day. Before you begin taking fish oil supplements, there are two important details to keep in mind: 1) If you get regular, daily sun exposure during the summer, chances are you don't need a D supplement during those three months of the year 2) Choose a fish oil supplement that's " molecularly distilled " to insure that toxins are kept to a minimum And, as always, talk to your doctor or health care provider before starting any new dietary supplement regimen. **************************************************** ....and another thing An HSI member who goes by the intriguing name of Xielolixii sent an e-mail with this question: " It would be nice to know how to determine organic soy vs. genetically altered soy. Any info on that? " I completely agree; it WOULD be nice if there were a way to determine organic from genetically altered soy. The problem is that different forms of soy show up as ingredients in thousands of products, and by and large you can assume that organic soy isn't being used. If you're buying a product that's primarily soy - like soy milk, for instance - you can look for a " certified organic " label. If that label isn't there you can assume it's not organic. And in many cases, soy that's not raised organically may be genetically altered. It's estimated that 20 percent or more of the U.S. soy crop is genetically engineered to survive regular spraying with a powerful chemical used to kill weeds. But while organic soy is arguably a better choice than non-organic, there's no reason to assume that it's necessarily healthy. If a product is highly processed from organically grown soy, it still has dubious nutritional value. But the problems with soy run even deeper than that. Here's how HSI Panelist Allan Spreen, M.D., addressed the soy topic in the e-alert " Adult Swim " (4/16/03): " I am not a fan of today's soy for a large list of reasons (even though the stuff is commonly labeled a 'health food'). The phytates on board block absorption of more than just minerals (proteins are also involved), and are only deactivated with soy that's been fermented. Tofu, textured soy protein and most other forms are anything but. Tempeh, miso, soy sauce made by the traditional method (most in the U.S. is not), and a few other forms are the only ones that qualify, and we don't see them much around here. " Today's commercial soybeans are not the same as in centuries past - they've been modified, which alone bothers me. However, the current hype about the phytoestrogens in soy is, to me, further cause for worry. Daidzein and genistein are named as reasons to procure soy, especially for women with menopausal difficulties. The jury may still be out on that one, assuming you have a form of soy with no phytates. However, there's little doubt that some significant estrogenic influence is involved, and that should be of concern. " For a much broader overview of the health hazards of soy, Dr. Spreen recommends what he calls a " somewhat scary " article titled " The Ploy of Soy " by Sally Fallon and Mary G. Enig, Ph.D., published online at westonaprice.org. It's important to note that this is a pro-dairy group. Still, this article and others that appear in the " Soy Alert! " section of that web site clearly demonstrate that soy is a far cry from health food. To Your Good Health, Jenny Thompson Health Sciences Institute **************************************************** Sources: " Vitamin D May Protect Against Prostate Cancer " NutraIngredients.com, 2/21/05, nutraingredients.com " Vitamin D May Lower Prostate Cancer Risk " Jeanie Lerche Davis, WebMD Medical News, 2/18/05, my.webmd.com " Test Values and Treatment for Vitamin D Deficiency " Dr. Joseph Mercola, 2/23/02, mercola.com " Vitamin D supplementation, 25-Hydroxyvitamin D Concentrations, and Safety " Reinhold Vieth, M.D., American Journal of Clinical Nutrition, Vol. 69, No. 5, May 1999, ncbi.nlm.nih.gov **************************************************** Copyright ©1997-2005 by www.hsibaltimore.com, L.L.C. The e-Alert may not be posted on commercial sites without written permission. ******* Quote Link to comment Share on other sites More sharing options...
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