Guest guest Posted July 9, 2004 Report Share Posted July 9, 2004 > " HSI - Jenny Thompson " > <HSIResearch > Let the Sun Shine > Thu, 08 Jul 2004 16:11:05 -0400 > > Let the Sun Shine > > Health Sciences Institute e-Alert > > Thursday July 08, 2004 > > ************************************************************** > Dear Reader, > > If you have type 2 diabetes, or if you've been > diagnosed with a > pre-diabetic condition, you may be deficient in one > vitamin that > could help make a big difference in your health. > > I'm not talking about vitamin C or vitamin E, > although both of > these vitamins have been shown to be essential in > helping prevent > kidney disease in diabetics (see the e-Alert " Take > 2 " 7/28/03). > > According to new research from the American Journal > of Clinical > Nutrition, vitamin D may play a key role in glucose > metabolism. > But how do you know if you're vitamin D deficient? > And what are > the best sources? > > -- > My " what " level? > -- > > Off hand, do you know what your 25-hydroxyvitamin D > level is? > > Neither do I. But the next time my doctor draws > blood I'm going to > ask him to make a note of the level of this marker > (also known as > 25(OH)D), because it's the best way to tell if > you're getting > enough vitamin D. > > Researchers at the University of California-Los > Angeles School of > Medicine (UCLA) recently examined the relation of > 25(OH)D to > insulin sensitivity in a group of 126 adults with > normal glucose- > tolerance. After determining the subjects' 25(OH)D > levels, the > UCLA team gauged the responsiveness of the pancreas > to glucose > using a technique called hyperglycemic clamp. > > Compared to subjects with the highest vitamin D > levels, those with > the lowest levels had symptoms of type 2 diabetes, > including > weaker pancreatic function and greater insulin > resistance. In > addition, 30 percent of the subjects with low > vitamin D levels had > one or more of the symptoms associated with > metabolic syndrome > x (MSX). Only 11 percent of those with normal > vitamin D levels > showed similar symptoms. > > In the e-Alert " X Marks the Spot " (4/15/04), I told > you about the > primary MSX indicators: > > * Excessive abdominal fat > * Elevated blood pressure (130/85 or higher) > * Low HDL cholesterol level (Less than 50 in women, > less than 40 > in men) > * Elevated Triglyceride level > * Elevated C-reactive protein level > * Fasting glucose level that indicates insulin > resistance/glucose > intolerance > > A combination of just three or more of these > symptoms creates an > elevated risk of heart disease and type 2 diabetes. > > -- > Light of day > -- > > 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. > > -- > Good values > -- > > As I mentioned above, the first step in determining > if your vitamin > D intake is sufficient is to assess blood serum > levels of 25(OH)D. > According to natural medical 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 and > prostate 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. So how can you make > sure you're > getting enough D? In addition to sun exposure and > dietary sources, > fish oil supplements provide a convenient way to > boost 25(OH)D. > > 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. > > But before you begin taking fish oil supplements, > there are two > important details to keep in mind: > > * 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 > * 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. > > ************************************************************** > To start receiving your own copy of the HSI e-Alert, > visit: > http://www.hsibaltimore.com/ealert/freecopy.html > Or forward this e-mail to a friend so they can > sign-up to > receive their own copy of the HSI e-Alert. > > ************************************************************** > > …and another thing > > If you bump up your fish intake to get more vitamin > D, there's one > potential drawback: mercury content. > > No doubt, this is a dilemma. And if you go looking > for information > that will help you avoid high-mercury fish, you > might come across > the July 2004 issue of Consumer Reports (CR), which > carries an > article titled " Is the Government too Lax in Advice > on Tuna > Consumption? " > > CR's assessment is that the government IS too lax – > as if we're all > waiting breathlessly to find out if the FDA might > lower their > recommendation about how much tuna pregnant women > should > eat. Do we really need the FDA's official ruling to > know that > pregnant women and young children should go easy on > tuna > intake? I don't think so. > > But I have another fish to fry here (and yes, that > pun was > completely intended – forgive me). > > The CR article notes that the government advises > young children > and women of childbearing age to avoid eating king > mackerel, > shark, swordfish, or tilefish. Meanwhile, as much as > 12 ounces of > lower-mercury fish each week is okay. > > Naturally this begs the question: What fish are > low-mercury? And > the answer: farm-raised catfish and trout, haddock, > salmon, and > flounder. THAT, however, is NOT the answer that CR > gives. > Here's CR's suggestion for low-mercury fish: fish > sticks. > > Fish sticks! > > Holy mackerel! That's CR's idea of sound nutrition? > They also > suggest that " fish sandwiches typically served in > restaurants " > contain low-mercury fish. So if I'm eating 12 ounces > of > McDonald's filet-o-fish each week, that's healthy? > > I have to say that the editors of Consumer Reports > are models of > consistency. When it comes to health and nutrition, > they miss by a > mile nearly every time. My advice to CR: It's > summertime, guys. > Give us some ratings on air conditioners and > barbeques. If we need > nutrition recommendations we'll rely on real > nutritionists. > > To Your Good Health, > > Jenny Thompson > Health Sciences Institute > > ************************************************************** > > Sources: > " Hypovitaminosis D is Associated with Insulin > Resistance and > Beta Cell Dysfunction " American Journal of Clinical > Nutrition, > Vol. 79, No. 5, May 2004, ncbi.nlm.nih.gov > " Low Vitamin D Linked to Insulin Resistance " David > Douglas, > Reuters Health, 6/29/04, reutershealth.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 > " Is the Government too Lax in Advice on Tuna > Consumption? " > Consumer Reports, July 2004, consumerreports.org > Quote Link to comment Share on other sites More sharing options...
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