Ultraviolet radiation suppresses obesity and symptoms of metabolic syndrome independently of vitamin D in mice fed a high-fat diet.
Diabetes. 2014 Nov;63(11):3759-69. doi: 10.2337/db13-1675.
Geldenhuys S 1, Hart PH 1, Endersby R 1, Jacoby P 1, Feelisch M 2, Weller RB 3, Matthews V 4, Gorman S 5.
1 Telethon Kids Institute, The University of Western Australia, Perth, Western Australia, Australia.
2 Clinical and Experimental Sciences, Faculty of Medicine, University of Southampton, Southampton General Hospital, Southampton, U.K.
3 University of Edinburgh, MRC Centre for Inflammation Research, Edinburgh, Scotland.
4 Laboratory for Metabolic Dysfunction, Harry Perkins Institute of Medical Research, Centre for Medical Research, The University of Western Australia, Perth, Western Australia, Australia.
5 Telethon Kids Institute, The University of Western Australia, Perth, Western Australia, Australia shelley.gorman at telethonkids.org.au.
The role of vitamin D in curtailing the development of obesity and comorbidities such as the metabolic syndrome (MetS) and type 2 diabetes has received much attention recently. However, clinical trials have failed to conclusively demonstrate the benefits of vitamin D supplementation. In most studies, serum 25-hydroxyvitamin D [25(OH)D] decreases with increasing BMI above normal weight. These low 25(OH)D levels may also be a proxy for reduced exposure to sunlight-derived ultraviolet radiation (UVR).
Here we investigate whether UVR and/or vitamin D supplementation modifies the development of obesity and type 2 diabetes in a murine model of obesity.
Long-term suberythemal and erythemal UVR significantly suppressed
- weight gain,
- glucose intolerance,
- insulin resistance,
- nonalcoholic fatty liver disease measures; and
- serum levels of fasting insulin,
- glucose, and
in C57BL/6 male mice fed a high-fat diet.
However, many of the benefits of UVR were not reproduced by vitamin D supplementation. In further mechanistic studies, skin induction of the UVR-induced mediator nitric oxide (NO) reproduced many of the effects of UVR.
These studies suggest that UVR (sunlight exposure) may be an effective means of suppressing the development of obesity and MetS, through mechanisms that are independent of vitamin D but dependent on other UVR-induced mediators such as NO.
Vitamin D supplementation = 2,280 IU/kg of feed = an OK amount
- Less weight gain in mice getting lots of vitamin D – June 2014
They used 15,000 IU/kg of feed which might be 24,000 IU/day for a human
- Hypothesis: Sun-produced nitric oxide reduces cardiovascular problems also by Dr. Richard Weller
- Metabolic Syndrome reduced 2X after one year of more sunlight - Nov 2011
- Metabolic Syndrome 3X less likely in college students with enough vitamin D – June 2014
- Daily Magnesium improved all aspects of metabolic profile – RCT July 2014 Magnesium helps too
- 40 percent less likely to gain weight if live at high altitude (no mention of UVB nor vitamin D) – April 2014
- Search VitaminDWiki for " nitric oxide" 197 items as of Jan 2015
- Hypothesis: Sun-produced nitric oxide reduces cardiovascular problems
- Beneficial effects of UV radiation other than via vitamin D production – June 2012
- 5 Amazing Properties of Sunlight You've Never Heard About
Sunlight Burns Fat: (subcutaneous, not visceral fat is used up while making vitamin D)
- UV better than vitamin D in reducing metabolic syndrome in mice – Thesis Aug 2013