Long-term vitamin D3 supplementation may have adverse effects on serum lipids during postmenopausal hormone replacement therapy.
Heikkinen AM, Tuppurainen MT, Niskanen L, Komulainen M, Penttilä I, Saarikoski S.
Eur J Endocrinol. 1997 Nov;137(5):495-502.
PMID: 9405029
CONCLUSIONS: Our results confirm the positive long-term effect of HRT with sequential estradiol valerate and cyproterone acetate on serum lipid concentrations. In addition, the results suggest that vitamin D3 supplementation may have unfavorable effects on lipids in postmenopausal women. Pure vitamin D3 treatment was associated with increased serum LDL cholesterol. Furthermore, the beneficial effects of HRT on serum LDL cholesterol content were reduced when estradiol valerate was combined with vitamin D3. However, the relevance of these associations to cardiovascular morbidity remains to be established.
This DRI report presents calcium, phosphorus, magnesium, vitamin D, and fluoride, all of which have key roles in developing and maintaining bone and other calcified tissues in the body. View or download the entire 454 page document or just selected sections below, or find information for obtaining the book version.
Dietary Reference Intakes for Calcium, Phosphorus, Magnesium, Vitamin D, and Fluoride (1997)
National Academy of Sciences. Institute of Medicine. Food and Nutrition Board.
Plasma calcidiol, season, and serum parathyroid hormone concentrations in healthy elderly men and women.
Dawson-Hughes B, Harris SS, Dallal GE.
Am J Clin Nutr. 1997 Jan;65(1):67-71.
PMID: 8988915
Plasma calcidiol and serum PTH concentrations were inversely related, with PTH rising slowly as calcidiol concentrations declined below 110 nmol/L (95 CI: 60, 168 nmol/L). More than 90% of the men and women had calcidiol concentrations below this value in the wintertime. The high prevalence of lower wintertime calcidiol values may increase risk of bone loss in elderly men and women.
Vitamin D deficiency: a worldwide problem with health consequences.
Holick MF, Chen TC.
Am J Clin Nutr. 2008 Apr;87(4):1080S-6S. Review.
PMID: 18400738
A reevaluation needs to take place of what the adequate intakes of vitamin D should be for children and adults. The literature over the past decade suggests that the Institute of Medicine recommendations in 1997 (83) are inadequate, and some experts including us suggest that both children and adults should take ≥800-1000 IU vitamin D/d from dietary and supplemental sources (4, 9, 77) when sunlight is unable to provide it. This recommendation, however, has not yet been embraced either by official government or pediatric organizations in the United States, Canada, or Europe for either children or adults.
Upper levels of vitamin D intake were set at 50 microg/d (2000 IU/d) for all ages. Some individuals would require higher levels than these to achieve serum 25-hydroxyvitamin D concentrations for optimal calcium absorption. So much new information on vitamin D and health has been collected since the requirements were set in 1997 that this nutrient is likely the most in need of revised requirements.
Vitamin D requirements: current and future.
Weaver CM, Fleet JC.
Am J Clin Nutr. 2004 Dec;80(6 Suppl):1735S-9S. Review. Erratum in: Am J Clin Nutr. 2005 Mar;81(3):729.
PMID: 15585797
Prevalence of vitamin D insufficiency in an adult normal population.
Chapuy MC, Preziosi P, Maamer M, Arnaud S, Galan P, Hercberg S, Meunier PJ.
Osteoporos Int. 1997;7(5):439-43.
PMID: 9425501
Vieth R, Fraser D.
Vitamin D insufficiency: no recommended dietary allowance exists for this nutrient.
CMAJ. 2002 Jun 11;166(12):1541-2.
PMID: 12074121
In fact, current recommendations for vitamin D are not designed to ensure anything. They are simply based on the old, default strategy for setting a nutritional guideline, which is to recommend an amount of nutrient similar to what healthy people are eating. This approach underlies the circular logic behind a familiar refrain about nutrition: "If you eat a good diet, you won't need supplements." By this logic, the answer to the question, "How much nutrient do you need?" is, "Whatever healthy people happen to be eating." The essential point, lost in the confusing terminology of modern nutrient recommendations, is that a recommended daily allowance (RDA) does not yet exist for vitamin D. Instead, the recommendations for it are referred to as "adequate intake" (AI).12,13 The AI for young adults (5 µg or 200 IU) was chosen to approximate twice the average vitamin D intake reported by 52 young women in a questionnaire-based study reported from Omaha, Neb., in 1997.13,14 Because the available evidence was acknowledged as weak, the Food and Nutrition Board of the US Institute of Medicine called its recommendation an AI.
Table of Contents
Ch. I Is calcidiol an active hormone? 1
Ch. II Vitamin D as a neurosteroid hormone : from neurobiological effects to behavior 29
Ch. III Inhibitors of vitamin D hydroxylases : mechanistic tools and therapeutic aspects 67
Ch. IV Vitamin D analogues as anti-cancer therapies 145
Ch. V Paricalcitol : a vitamin D2 analog with anticancer effects with low calcemic activity 169
Ch. VI Vitamin D use among older adults in U.S. : results form national surveys 1997 to 2002 181
Ch VII Vitamin D deficiency in migrants 199
Vitamin D is a fat-soluble steroid hormone precursor that contributes to the maintenance of normal levels of calcium and phosphorus in the bloodstream. Strictly speaking, it is not a vitamin since human skin can manufacture it, but it is referred to as one for historical reasons. It is often known as calciferol. The major biologic function of vitamin D is to maintain normal blood levels of calcium and phosphorus. Vitamin D aids in the absorption of calcium, helping to form and maintain strong bones. It promotes bone mineralisation in concert with a number of other vitamins, minerals and hormones. Without vitamin D, bones can become thin, brittle, soft or misshapen. Vitamin D prevents rickets in children and osteomalacia in adults -- skeletal diseases that result in defects that weaken bones. This book gathers international research on the leading-edge of the scientific front.