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Berkeley Wellness Alerts
February 23, 2010 | Comments: 12
How to Choose a Vitamin D Supplement
Because of growing evidence about the benefits of vitamin D—for bone health, muscle function, and possibly even prevention of some cancers and other illnesses—many people are rushing out to buy vitamin D pills. Here’s what to look for.
There are two main forms of vitamin D:
Vitamin D3 (cholecalciferol) is typically derived from lanolin from sheep’s wool. Less commonly, D3 comes from fish liver oil, a concern because of mercury, PCBs, and other possible contaminants—though reputable manufacturers can remove harmful compounds in processing. D3 is also the form our skin produces when exposed to sunlight and is the natural form found in food.
Vitamin D2 (ergocalciferol) comes from non-animal sources, such as fungi, that are exposed to ultraviolet light to convert their cholesterol-like substances, called sterols, into vitamin D.
Once consumed, both vitamin D2 and vitamin D3 are converted in the body to the active form. But some research strongly suggests that D3 is preferable to D2. One study, for example, found that D2 was less than one-third as potent as D3 and that it was shorter-acting.
Reading labels: The type of vitamin D is listed on supplement bottles in the ingredients (and sometimes in the “Supplement Facts” panel). Look for D3 or cholecalciferol, preferably not from fish liver oil. The same company may use D3 in some of its products but D2 in others. If you’ve been taking a supplement with D2 (ergocalciferol), you are still getting benefits, but consider switching to a product with D3 when you are done with that bottle. Some strict vegetarians may prefer D2 since it’s not derived from animals, but because it’s less potent, higher doses are needed to get the same effect as D3.
Many vitamin D pills, multivitamins, and bone formulas—especially those from major brands like One-A-Day and Centrum—contain D3, as does most milk and other fortified foods. Quite a few health-food store brands, however, may still contain D2.
Your D needs: A growing number of experts believe that the current recommended daily intake levels for vitamin D (which range from 200 to 600 IU, based on age) are too low, and that a better goal for everyone is 800 to 1,000 IU a day—especially if you are over 60 (the ability to manufacture vitamin D from sunlight and utilize it declines with age), have darker skin (which makes less vitamin D), live at northern latitudes, or are housebound. You can get some vitamin D from foods—such as milk, fatty fish, and foods fortified with vitamin D—but it’s nearly impossible to get 800 to 1,000 IU without also taking a supplement.
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i enjoy this site i just signed up for it,im 41 yrs.old and i started taking vitamind 400iu is that safe r do i need more...jeep up the good work..
Posted by: Unknown | February 24, 2010 10:31 PM
HI, JUST SIGNED UP FOR THE SITE. i'M 80 YRS. OLD HAVE BEEN TAKING 1000 IU OF VIT. D3 FOR THE PAST YEAR. MY HEALTH IS GOOD; MY BIGGEST COMPLAINT IS KNEE ARTHRITIS.
Posted by: Unknown | February 25, 2010 3:40 PM
New to this site and find it very informative. Question about Vitamin D requirements. Are the requirements the same for men and women over the age of 65?
Posted by: Unknown | February 27, 2010 10:02 AM
It's the same for men and women. The Wellness Letter recommends 800 to 1,000 IU for most people, especially those over 65. For more info see: http://www.wellnessletter.com/html/wl/2008/wlFeatured0208.html The Editors
Posted by: Michael Goldman | February 27, 2010 10:36 AM
As a supplement I take 400 iu daily as a tablet (D3). Some foods that I eat are also fortified with moderate doses. As it is winter I have a few minutes in front of a sunlamp (ultra-violet) alternate days, and in the summer will sunbathe regularly. A short time in the sun (not winter time) will give me many thousands of units of vitamin D. The great advantage of sunbathing is the 'feel good' factor which all humans, and probably animals, find.
Posted by: Mike M | March 3, 2010 2:56 PM
Question about vitamin D. I am 70 years old, living north where we don't get enough vitamin D during winter from the sun.
I am thinking to buy a Vitamin D Fluorescent lamp like Sperti lamps. Are these lamps safe? Are they worth for the money? Comparing with Vitamin D pills, which do you recommend? I am active year around, and I think I get enough vitamin D during summer, but not enough in winter. Thanks in advance.
Posted by: Unknown | March 6, 2010 8:27 AM
Re sun lamps vs supplements: See the second Q & A here: http://www.wellnessletter.com/html/wl/2009/wlAskExperts0509.html We don't know if any of the lamps are safer, but will look into it. You might get your blood levels of D measured. D supplements are a lot cheaper than special lamps. -- The Editors
Posted by: Michael Goldman | March 6, 2010 8:34 AM
Sun kills skin. Melanoma is not a good thing to get. It is very important for darker skinned individuals to take vit D as they do not make it very well in the skin.
Posted by: petersenrj | March 6, 2010 10:59 AM
When taking Vit D supplements, is it important to take it with food containing fats, given it's a fat soluable vitamin, or is it just as effective to take it with any liquid, and not worry about what accompanies it when using it as a supplement. Thank you!
Posted by: Mambojazz | July 25, 2010 7:50 PM
I have been told that Vitamin D increases the risk of kidney stone formation in those who are stone-formers. Although I am not a researcher or a physician, I can't find any studies that isolate Vitamin D as a specific variable in stone formation. Is this a supposition, or has it been confirmed by appropriate, peer-reviewed research? Is there information about this that I, as a lay person, can access?
Posted by: bonniebal | February 25, 2011 12:12 PM
We can find no evidence linking vitamin D to kidney stones, just a few studies linking calcium (sometimes given with D) to certain types of stones. Here is what the noted vitamin D researcher Dr. Robert Heaney says: "Kidney Stones are NOT caused by vitamin D". See http://www.grassrootshealth.net/blog/kidney-stones-not-caused-by-vitamin-d/118 -- The Editors
Posted by: Michael Goldman | February 25, 2011 2:36 PM
Here's the fact on vitamin d3.Everyone should be taking vitamin d3.D3 is much easier absorbed then vitamin d2.How much is enough ?Average or rule of thumb is 35 IU's per every pound of weight,example 100 lbs.=3500 iu's daily..best way to track your levels is to take a vitamin d blood test called 25 oh d test and make sure its not 1,25 ohd.Your levels should be between 55ng/ml -- 70 ng/ml..Anyone with arthritis I can assure you will definitely have low levels of vitamin d in the body ,probably around 25 to 40 ng/ml.Vitamin d is needed to help calcium absorb in the body.We as a nation are being told that the sun and to much vitamin d can be very dangerous to your health and that since it is a fat soluble vitamin can become very toxic in the ,and although that is very possible it would take major amounts of vitamin d for that to occur ..the fear is being placed in us by the powers that be in order to keep us sick and to keep us going back to the doctors for ,arthritis meds,as well as many others.The reason why we are so deficient in vitamin d is that they are placing fear into us by telling us that we should not go into the sun without using some type of sunscreen or block.Thats the problem.You see the sun has uvb rays {which by the way are the rays that the body needs to convert to vitamin d withing the body which also are an extremely powerful antioxidant}, and uva rays which are the bad rays.when exposed to the sun both the rays are helpful to eachother ,but when we place sunscreen or block on we are actually blocking the uvb rays and allowing the uva rays to enter the body.This is what sunscreens do.Allowing the uva rays inside the body acts as as an oxidant which as we all know is bad and thats why we need antioxidants.With all of this said I want to say that just 20 to 30 minutes in the sun can create 10,000 to 20,000 ius which is very safe but extended periods ,hours sunbathing is not healthy.If going to the beach sunbathe for a little while ,then sit in shade under an umbrella for a while,and use coconut oil and rub it on the skin all over to help protect the skin. www.ginos-passion.com
Posted by: gacfratelli | February 25, 2011 6:37 PM