Here are some great reasons for taking Vitamin D--I take 5000 IU/day myself, Dr. Z:
One of the most replicated findings in vitamin D research is that the higher a person’s vitamin D level, the less one weighs; the lower the vitamin D, the more one weighs. We report on a study published last month where researchers found that in just 12 weeks, the vitamin D group lost 5 more pounds than the control group, suggesting vitamin D3 as a potential addition to a weight loss program. Researchers also found improved scores in lipoprotein/cholesterol ratios for better heart health in the vitamin D group versus the placebo group.
What about the possibility of vitamin D playing a causative role, not just an associative role, in obesity and body mass? That is, to a limited extent, does vitamin D act like a diet pill? Published last month, Dr. Selehpour of the Tehran University of Medical Sciences described some interesting results in her randomized controlled trial.1
In this RCT of 77 overweight and obese women with an average age of 38, researchers randomly assigned them to receive either a small daily dose of vitamin D3 (1,000 IU/day) or placebo for 12 weeks. At the end of 12 weeks, the vitamin D3 group lost five more pounds than the control group. They also found improved scores in lipoprotein/cholesterol ratios for better heart health in the vitamin D group verses placebo.1 Which brings some readers to the question: “If I want to diet, how much vitamin D should I take?”
In a study published in 2009, researchers at the University of Minnesota showed that higher vitamin D levels at the start of a low-calorie diet predict weight loss success. On average, overweight subjects had pre-diet baseline vitamin D levels considered in the insufficient range. However, the researchers found that pre-diet vitamin D levels predicted weight loss in a linear relationship. For every increase of 1 ng/mL in 25(OH)D level, subjects lost almost a half pound more on their 11-week calorie-restricted diet.2
Cardiovascular Risk
Dr. Selehpour reported that HDL cholesterol levels increased in the vitamin D group, but decreased in the placebo group. LDL cholesterol levels displayed the same trend in the groups, with increases observed in the vitamin D group.1
However, an increase was observed in the ratio of LDL to ApoB, the main apolipoprotein of LDL cholesterol that is responsible for the transport of cholesterol to tissues.1
This result “indicates less atherogenic properties of LDL cholesterol particles, whereas this ratio declined in the placebo group indicating that LDL cholesterol particles were smaller and higher density,” explained the researchers.
This study has shown that a daily supplementation of 1,000 IU of vitamin D3 has a beneficial effect on HDL cholesterol, apoA-1 concentrations, apoA-1:apoB-100 and LDL cholesterol:apoB-100 ratios in overweight and obese women.1
Is Vitamin D Absorbed in Fat?
In a 2012 published study of 686 adults, researchers at Creighton University found that circulating vitamin D (25(OH)D) levels were inversely correlated with total body weight, but not correlated with the amount of a patient’s fat or muscle. There was no evidence for sequestration of supplemental or endogenous vitamin D3. Researchers concluded that vitamin D replacement therapy needs to be adjusted for body size to achieve desired 25(OH)D plasma concentrations.3
These researchers calculate that if you want the average patient to have a 25(OH)D level of 40 ng/ml, that person needs 70-80 IU/kg/day. A 250 pound man would need 7-8,000 IU/day from all sources, while a 125 pound woman would need 3,500-4,000 IU/day from all sources. Because it is difficult to adjust for daily variations in un-sunscreen protected whole-body sun exposure, a typical (non-dieting) adult recommendation is simply 5,000 IU/day.
Recommendation
John Cannell, MD, founder of the Vitamin D Council, recommends 5,000 IU/day oral vitamin D3 for healthy, average weight adults (125-200 pounds). If the patient is above this weight, 32 IU per pound per day is a good rule of thumb. This means that a 300 pound person would need 10,000 IU/day, though it wouldn’t surprise him if they needed more (because overweight people tend to spend less active time in the sun). The only way to know is to test blood levels (25(OH)D). As the dieting patients’ weight decreases, it is appropriate to reduce the dose.
Dr. Cannell comments that he “doubts that vitamin D is a classic diet pill. It may work by increasing your activity as your “get up and go” is back. Just lying on the sofa popping vitamin D pills will get you nowhere, however. Dieters are encouraged to follow that urge to take a walk, clean out the garage, and take that weekend trip.”
Vitamin D3 is 10x as Effective as D2
Vitamin D3 is the form of vitamin D that occurs naturally in the human body, whereas vitamin D2 is produced by irradiating yeast with ultraviolet light. Since the 1930's, it has been generally assumed that vitamin D3 and D2 are equally effective in humans. Researchers in 2004 found that while initial 25(OH)D plasma response was similar for D2 and D3 in human volunteers, the calculated area under the curve from day 0 to infinity indicated the potency of vitamin D2 is only 10.6% that of vitamin D3.4
Professor Goran Bjelakovic evaluated 50 randomized controlled trials (RCTs) that included a total of 92,000 participants who took some form of vitamin D. Mortality rates were reported as either primary or secondary outcomes. While 74,000 participants in 32 trials used D3, the remaining 18,000 participants in the other 12 trials took D2. He discovered that the relative risk increased by 2% for participants in the vitamin D2-group, while those in the D3-group had a relative riskreduction of 6%.5
Thus Rejuvenation Science® Vitamin D3 is significantly more effective than prescription Drisdol (D2). Fortified foods (milk, cheese, bread, etc. which use the cheaper vitamin D2 without specifying the form of vitamin D on the label) are generally poor sources of vitamin D.
Safety and Toxicity
Recommended doses of Vitamin D are increasing with the increase in published studies describing vitamin D benefits. I thought our friend, Dr. Cannell’s discussion on Vitamin D safety and toxicity published in August 2010 to be timely information for you to ensure safety in your recommendations. After reading, I expect that you will feel more comfortable recommending moderate (5,000 – 10,000 IU) daily doses of Vitamin D3 in conjunction with 25(OH)D testing. Please request a copy, by responding to this email, of my 3-page Vitamin D Safety and Toxicity review.
Conclusion
These studies suggest that Vitamin D3 may be part of a weight loss or weight maintenance program. Rejuvenation Science® provides Vitamin D3 in 1000, 2000, 5000, and 10000 IU doses. There are 1,000 IU of vitamin D3 in Maximum Vitality® multivitamin and we have a special Pediatric liquid Vitamin D3 formula. Here is a link to our Vitamin D product options: Vitamin D Products. You may review a number of new Vitamin D studies, as well as an article: Compelling Research Supports Increased Vitamin D Intake.
1. Salehpour A, Shidfar F, Hosseinpanah F, Vafa M, Razaghi M, Hoshiarrad A, Gohari M. Vitamin D3 and the risk of CVD in overweight and obese women: a randomised controlled trial. Br J Nutr. 2012 Feb 9:1-8. [Epub ahead of print]
2. Sibley S. Successful Weight Loss with Dieting is Linked to Vitamin D Levels. Presentation at The Endocrine Society’s 91stAnnual Meeting in Washington, D.C. 2009.
3. Drincic AT, Armas LA, Van Diest EE, Heaney RP. Volumetric Dilution, Rather Than Sequestration Best Explains the Low Vitamin D Status of Obesity. Obesity (Silver Spring). 2012 Jan 19. doi: 10.1038/oby.2011.404.
4. Armas LAG, et al. Vitamin D2 is much less effective than vitamin D3 in humans. J Clin Endocrinol Metab 2004;89:5387-5391.
5. Bjelakovic G, Gluud LL, Nikolova D, Whitfield K, Wetterslev J, Simonetti RG, Bjelakovic M, Gluud C. Vitamin D supplementation for prevention of mortality in adults. Cochrane Database Syst Rev. 2011 Jul 6;(7):CD007470.
