A detergent is then added to extract the crude lanolin. This is then saponified: a process which converts the fatty component into chemicals that can be removed by centrifugation.
This is illuminated by ultraviolet light to form Vitamin D3, mimicking the reaction that occurs in our skin. Certain people, such as vegans, may feel uneasy about using a product that comes from sheep. Furthermore, lanolin can also cause allergic reactions and can be the basis for some apparent allergies to wool. The Vitamin D3 is extracted using methods similar to those in the pharmaceutical industry, using water and plant ethanol, and applying pressure.
If all this has made you think twice about where your vitamin supplements come from, the good news is that during the summer months at least you should be able to get enough Vitamin D simply by heading outside every day. Home Hormones Vitamin D. Vitamin D Vitamin D is a hormone produced by the kidneys that helps to control the concentration of calcium in the blood and is vital for the development of strong bones.
Alternative names for vitamin D Calcitriol or 1,dihydroxyvitamin D ; ergocalciferol vitamin D 2 ; cholecalciferol vitamin D 3 ; calcidiol hydroxyvitamin D What is vitamin D?
How is vitamin D controlled? What happens if I have too little vitamin D? What happens if I have too much vitamin D? Last reviewed: Feb Prev. Related Endocrine Conditions. Related Hormones. Clin Pediatr Phila ; 46 —4. High prevalence of vitamin D insufficiency in black and white pregnant women residing in the northern United States and their neonates. J Nutr. Addressing the health benefits and risks, involving vitamin D or skin cancer, of increased sun exposure. Hollis BW.
Circulating hydroxyvitaminDlevels indicative of vitamin D sufficiency: Implications for establishing a new effective dietary intake recommendation for vitamin D. The effect of sun exposure on hydroxyvitamin D concentrations in young healthy subjects living in the city of Sao Paulo, Brazil. Braz J Med Biol Res. Vitamin D status and its adequacy in healthy Danish peri-menopausal women: Relationships to dietary intake, sun exposure and serum parathyroid hormone.
Br J Nutr. Vitamin D deficiency: A worldwide problem with health consequences. Vitamin D and skin physiology: A D-lightful story. Serum hydroxyvitaminDstatus of the US population: — compared to — Sunscreens suppress cutaneous vitamin D3 synthesis. J Clin Endocrinol Metab. Increased skin pigment reduces the capacity of skin to synthesise vitamin D3.
Higher prevalence of vitamin D deficiency is associated with immigrant background among children and adolescents in Germany. Decreased bioavailability of vitamin D in obesity. Steroid and xenobiotic receptor and vitamin D receptor crosstalk mediates CYP24 expression and drug-induced osteomalacia.
J Clin Invest. Adams JS, Hewison M. Hypercalcemia caused by granuloma forming disorders. In: Favus MJ, editor. Primer on the metabolic bone diseases and disorders of mineral metabolism. Vitamin D repletion in patients with primary hyperparathyroidism and coexistent vitamin D insufficiency. Prevalence of vitamin D inadequacy among postmenopausal North American women receiving osteoporosis therapy. Frequency of osteomalacia and osteoporosis in fractures of the proximal femur.
High prevalence of vitamin D inadequacy and implications for health. Mayo Clin Proc. Treatment of hypovitaminosis D in infants and toddlers. Resurrection of vitamin D deficiency and rickets. Fracture prevention with vitamin D supplementation: A meta-analysis of randomized controlled trials. Fall prevention with supplemental and active forms of vitamin D: A meta-analysis of randomised controlled trials. Picciano MF. Nutrient composition of human milk.
Pediatr Clin North Am. Prevention of rickets and vitamin D deficiency in infants, children, and adolescents. Ultraviolet light: A hazard to children. Influence of season and latitude on the cutaneous synthesis of vitamin D3: Exposure to winter sunlight in Boston and Edmonton will not promote vitamin D3 synthesis in human skin. An evaluation of the relative contributions of exposure to sunlight and of diet to the circulating concentrations of hydroxyvitamin D in an elderly nursing home population in Boston.
Vitamin D absorption in healthy subjects and in patients with intestinal malabsorption syndromes. Modern Nutrition in Health and Disease. Philadelphia: Lippincott Williams and Wilkins; Malone M. Recommended nutritional supplements for bariatric surgery patients. Ann Pharmacother. Vitamin D and the bariatric surgical patient: A review. Obes Surg. Vitamin D: A D-lightful health perspective. Nutr Rev. Human plasma transport of vitamin D after its endogenous synthesis. The role of the pharmacist in the identification and management of secondary hyperparathyroidism.
US Pharm. Hypovitaminosis D in medical inpatients. Am J Physiol Renal Physiol. Peterlik M, Cross HS. Vitamin D and calcium deficits predispose for multiple chronic diseases. Eur J Clin Invest. Vitamin D and human health: Lessons from vitamin D receptor null mice. Endocr Rev. FGFKlotho signaling stimulates proliferation and prevents vitamin D-induced apoptosis. J Cell Biol. Toll-like receptor triggering of a vitamin D-mediated human antimicrobial response. Injury enhances TLR2 function and antimicrobial peptide expression through a vitamin D-dependent mechanism.
Cod liver oil, vitamin A toxicity, frequent respiratory infections, and the vitamin D deficiency epidemic. Ann Otol Rhinol Laryngol. Serum vitamin D concentration and prostate cancer risk: A nested case-control study. Vitamin D and calcium intakes and breast cancer risk in pre- and postmenopausal women. Plasma hydroxyvitamin D levels and risk of incident hypertension. Serum hydroxyvitamin D, ethnicity, and blood pressure in the third National Health and Nutrition Examination Survey.
Am J Hypertens. Optimal vitamin D status attenuates the age-associated increase in systolic blood pressure in white Americans: Results from the third National Health and Nutrition Examination Survey. Vitamin D status and health correlates among German adults. Eur J Clin Nutr. That's where a sunscreen comes in. Look for a product with an SPF of 30 or higher. Apply your sunscreen early, often, and liberally.
These many factors explain why vitamin D deficiencies are shockingly common in the United States. And low levels of vitamin D are common even in apparently healthy young adults; in one study, more than a third of people between the ages of 18 and 29 were deficient. Numbers can never tell the whole story, but in this case, "D-ficiencies" add up to a wide range of health concerns. It's a paradox: Skeletal health is the best-known contribution of vitamin D, but it has also become the most controversial.
Although doctors agree that vitamin D deficiency increases the risk of osteoporosis and fractures, they disagree about the benefits and optimal dosage of supplements. Without enough vitamin D, the intestines cannot efficiently absorb calcium. But because blood calcium is critical for neuromuscular and cardiac function, the body does not allow levels to fall. Instead, it pours out parathyroid hormone, which mobilizes calcium from bone. Blood calcium levels remain normal, so your heart and nerves keep working nicely.
But your bones bear the brunt: As bone calcium density falls, bones become weak and fracture-prone. Most studies show that a lack of vitamin D increases the risk of osteoporosis and the likelihood of hip and other non-spinal fractures.
But there is considerable disagreement about how much supplements reduce the risk of fractures. Some studies include only women, others both men and women; some include only frail, elderly, or institutionalized subjects, others physically active people; some use vitamin D alone, others a combination of D and varying doses of calcium; and some administer international units IU of vitamin D a day, others up to IU a day.
Some men mistakenly dismiss osteoporosis as a women's worry, but none fail to recognize the importance of prostate cancer. Vitamin D has an important role in regulating cell growth.
Laboratory experiments suggest that it helps prevent the unrestrained cell multiplication that characterizes cancer by reducing cell division, restricting tumor blood supply angiogenesis , increasing the death of cancer cells apoptosis , and limiting the spread of cancer cells metastasis. Like many human tissues, the prostate has an abundant supply of vitamin D receptors. And, like some other tissues, it also contains enzymes that convert biologically inactive 25 OH D into the active form of the vitamin, 1,25 OH 2D.
These enzymes are much more active in normal prostate cells than in prostate cancer cells. In , Harvard's Health Professionals Follow-up Study of 47, men reported that a high consumption of calcium supplements was associated with an increased risk of advanced prostate cancer. The risk was greatest in men getting more than 2, mg of calcium a day from a combination of supplements and food. Since then, other studies have confirmed a link between very high levels of calcium intake and increased risk, but they have exonerated dietary calcium consumption.
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