Benefits of Sunlight: A Bright Spot for Human Health 5
Part 5 of Benefits of Sunlight discusses many of the other health links tied to Vitamin D, UV light, and sunlight exposure. Multiple Sclerosis, diabetes, cardiovascular disease, hypertension, blood pressure, arthritis, immunity diseases, colon cancer, lupus are some of the health diseases improved by sunlight exposure.
Benefits of Sunlight: A Bright Spot for Human Health
M. Nathaniel Mead
Other Health Links
Various studies have linked low 25(OH)D levels to diseases other than cancer, raising the possibility that vitamin D insufficiency is contributing to many major illnesses. For example, there is substantial though not definitive evidence that high levels of vitamin D either from diet or from UVR exposure may decrease the risk of developing multiple sclerosis (MS). Populations at higher latitudes have a higher incidence and prevalence of MS; a review in the December 2002 issue of Toxicology by epidemiology professor Anne-Louise Ponsonby and colleagues from The Australian National University revealed that living at a latitude above 37° increased the risk of developing MS throughout life by greater than 100%.
Still to be resolved, however, is the question of what levels of vitamin D are optimal for preventing the disease—and whether the statistical associations reflect different gene pools rather than different levels of 25(OH)D. (Interestingly, Holick reported in the August 1988 issue of The Journal of Clinical Endocrinology & Metabolism that no previtamin D3 formed when human skin was exposed to sunlight on cloudless days in Boston, at 42.2°N, from November through February or in Edmonton, at 52°N, from October through March.)
“Scientific evidence on specific effects of vitamin D in preventing multiple sclerosis (MS) or slowing its progression is not sufficient,” says Alberto Ascherio, a nutritional epidemiologist at the Harvard School of Public Health. “Nevertheless, considering the safety of vitamin D even in high doses, there is no clear contraindication, and because vitamin D deficiency is very prevalent, especially among MS patients, taking vitamin D supplements and getting moderate sun exposure is more likely to be beneficial than not.”
As with MS, there appears to be a latitudinal gradient for type 1 diabetes, with a higher incidence at higher latitudes. A Swedish epidemiologic study published in the December 2006 issue of Diabetologia found that sufficient vitamin D status in early life was associated with a lower risk of developing type 1 diabetes. Nonobese mice of a strain predisposed to develop type 1 diabetes showed an 80% reduced risk of developing the disease when they received a daily dietary dose of 1,25(OH)D, according to research published in the June 1994 issue of the same journal. And a Finnish study published 3 November 2001 inThe Lancet showed that children who received 2,000 IU vitamin D per day from 1 year of age on had an 80% decreased risk of developing type 1 diabetes later in life, whereas children who were vitamin D deficient had a fourfold increased risk. Researchers are now seeking to understand how much UVR/vitamin D is needed to lower the risk of diabetes and whether this is a factor only in high-risk groups.
There is also a connection with metabolic syndrome, a cluster of conditions that increases one’s risk for type 2 diabetes and cardiovascular disease. A study in the September 2006 issue of Progress in Biophysics and Molecular Biology demonstrated that in young and elderly adults, serum 25(OH)D was inversely correlated with blood glucose concentrations and insulin resistance. Some studies have demonstrated high prevalence of low vitamin D levels in people with type 2 diabetes, although it is not clear whether this is a cause of the disease or an effect of another causative factor—for example, lower levels of physical activity (in this case, outdoor activity in particular).
People living at higher latitudes throughout the world are at higher risk of hypertension, and patients with cardiovascular disease are often found to be deficient in vitamin D, according to research by Harvard Medical School professor Thomas J. Wang and colleagues in the 29 January 2008 issue of Circulation. “Although the exact mechanisms are poorly understood, it is known that 1,25(OH)D is among the most potent hormones for down-regulating the blood pressure hormone renin in the kidneys,” says Holick. “Moreover, there is an inflammatory component to atherosclerosis, and vascular smooth muscle cells have a vitamin D receptor and relax in the presence of 1,25(OH)D, suggesting a multitude of mechanisms by which vitamin D may be cardioprotective.”
To determine the potential link betwen sun exposure and the protective effect in preventing hypertension, Rolfdieter Krause of the Free University of Berlin Department of Natural Medicine and colleagues exposed a group of hypertensive adults to a tanning bed that emitted full-spectrum UVR similar to summer sunlight. Another group of hypertensive adults was exposed to a tanning bed that emitted UVA-only radiation similar to winter sunlight. After three months, those who used the full-spectrum tanning bed had an average 180% increase in their 25(OH)D levels and an average 6 mm Hg decrease in their systolic and diastolic blood pressures, bringing them into the normal range. In constrast, the group that used the UVA-only tanning bed showed no change in either 25(OH)D or blood pressure. These results were published in the 29 August 1998 issue of The Lancet. According to Krause, who currently heads the Heliotherapy Research Group at the Medical University of Berlin, a serum 25(OH)D level of at least 40 ng/mL should be adequate to protect against hypertension and other forms of cardiovascular disease (as well as cancers of the prostate and colon).
William Grant, who directs the Sunlight, Nutrition, and Health Research Center, a research and education organization based in San Francisco, suspects that sun exposure and higher 25(OH)D levels may confer protection against other illnesses such as rheumatoid arthritis (RA), asthma, and infectious diseases. “Vitamin D induces cathelicidin, a polypeptide that effectively combats both bacterial and viral infections,” Grant says. “This mechanism explains much of the seasonality of such viral infections as influenza, bronchitis, and gastroenteritis, and bacterial infections such as tuberculosis and septicemia.” For example, RA is more severe in winter, when 25(OH)D levels tend to be lower, and is also more prevalent in the higher latitudes. In addition, 25(OH)D levels are inversely associated with the clinical status of RA patients, and greater intake of vitamin D has been linked with lower RA risk, as reported in January 2004 in Arthritis & Rheumatism.
Some reports, including an article in the October–December 2007 issue of Acta Medica Indonesiana, indicate that sufficient 1,25(OH)D inhibits induction of disease in RA, collagen-induced arthritis, Lyme arthritis, autoimmune encephalomyelitis, thyroiditis, inflammatory bowel disease, and systemic lupus erythematosus. Nonetheless, interventional data are lacking for most autoimmune disorders and infectious diseases, with the exception of TB.
Source: http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=2290997 , http://www.scribd.com/doc/6480898/Benefits-of-Sunlight-A-Bright-Spot-for-Human-Health
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Tags: arthritis, blood pressure, cardiovascular disease, colon cancer, diabetes, Dr. William Grant, hypertension, immunity, lupus, multiple sclerosis
This entry was posted on Sunday, September 15th, 2024 at 9:36 am and is filed under Articles.
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tltandr said:
on October 12th, 2009It is SUNBIOPHOTON that entering our eyes and triggering the production of vitD by way of retina-pineal route to the PINEALGLAND.
NOT BY UV ON HUMAN SKIN TISSUE that is JUST PRODUCING CANCER OF THE SKIN.
By SUNZAING during sunrising and NOT EXCEEDING 7 a.m. or during daytime by INDIRECT SUNLIGHT Sunbiophoton triggering the activation the DNA of the PINEALGLAND in SECREETING vitD.
DR TAN tjiauw liat
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