The evidence has been mounting for some time that sunlight exposure can halt osteoporosis in its tracks. For example, an investigation from Spain in 2008 concluded that women who actively participated in sun exposure had one-eleventh the chance of a hip fracture as those who stayed indoors. There is no bone drug that can create such dramatic results, and neither has vitamin D supplementation been able to create such results, although vitamin D was doubtlessly a major factor in the results of the Spanish research.
The beauty of sunlight exposure is the fact that it is irrefutably capable of reversing osteoporosis. A study from Japan furnishes the proof: Over twelve months, 129 elderly, hospitalized women were exposed to regular sunlight and another 129 stayed received no sunlight. The results were impressive. In these sedentary women, the sunlight group increased bone mass by an average 3.1%; in the non-sunlight-exposed group, it decreased by 3.3%. More importantly, the women who had the benefit of sunlight had only one bone fracture in their group. The sunlight-deprived group had six fractures! Sunlight reversed osteoporosis. Vitamin D produced by the skin in response to sunlight likely played a large role in the reversal; blood levels increased by nearly 400% during the year. Nevertheless, the women remained vitamin D deficient, reaching levels of about 19 ng/ml. This may mean that something beyond vitamin D production—perhaps another photoproduct produced by the skin in response to sunlight—made a difference. Certainly, no study using vitamin D supplements alone has produced such results.
The aforementioned studies conclusively demonstrate that sunlight is the key to strong, healthy bones; nevertheless, corroborating information continues to emerge. Recently published research from Sweden showed the results of an investigation regarding the correlations among fracture rates, latitude and UV radiation (the light spectrums of sunlight that stimulate the skin to produce vitamin D and other photoproducts such as nitric oxide, endorphins, etc.). The higher the latitude, the lower is the exposure to UV radiation. The investigators showed that there were statistically significant correlations between hip-fracture rates and latitude as well as UV radiation in Sweden. Obviously, this is another instance of sunlight exposure preventing osteoporosis and fracture.
Osteoporosis, like many other degenerative diseases, is an absolutely unnecessary malady. Plenty of sunshine and a healthful nutrition program can prevent and even reverse these illnesses.
 Larrosa, M. Vitamin D deficiency and related factors in patients with osteoporotic hip fracture. Med Clin (BARC) 2008;130:6-9.
 Sato, Y. Metoki N, Iwamoto J, Satoh K. Amelioration of osteoporosis and hypovitaminosis D by sunlight exposure in stroke patients. Neurology 2003;61:338-42.)
 Nilson F, Moniruzzaman S, Andersson R. A comparison of hip fracture incidence rates among elderly in Sweden by latitude and sunlight exposure. Scand J Public Health. 2013 Nov 21. [Epub ahead of print].