In Parashas Vayishlach, we read about the famous battle between our forefather Ya'acov and the angel of Esav. This wrestling match lasted throughout the night with the two opponents locked in a head-to-head match for survival. As dawn approached, Jacob's nemesis took a cheap shot below the belt dislocating Yaacov's hip. As a result, we are told that Yaacov developed a limp, and to commemorate that incident, we Jews do not eat the sciatic nerve.
In this story, which is found in Braishis 32:32, we find after their battle that"... the sun shone for him." Rashi, the classical 10th century commentary, asks what do the words "for him" mean. When the sun shines is it not shining `for everyone'?! Rashi answers by telling us that the sun had a specific benefit "for him," for Yaakov avinu, and that was to heal his hip, that this musculoskeletal injury to Ya'akov avinu's sciatic nerve and hip was healed by the mechanisms that Ha-Shem implanted in the rays of the sun! And as the Prophet Malachi puts it "It is a sun of charity, with healing on its wings." (This is the source for the verse which serves as the inspiration for my friend Avrohom Greenbaum's book, "WIngs of the Sun", BTW).
What, though, are the sources from whence the sun received its incredible healing properties?
There are two answers to this: One is a medrash concerning Yaakov avinu's grandfather, Avraham. The medrash that tells us that our forefather Avraham used to wear a Kameah (either an amulet or a jewel) around his neck. Anyone who was sick would look at this kameah, and be healed. After he died, Ha-Shem took the kameah and hung it around the sun.
But going back to the beginning, our sages tell us that the light we see from the sun today, is only a fraction of the light it originally had, that its full light is hidden, our world being unworthy of it, but that in the future, in the messianic age, it will again be revealed in its full glory. During of the plague of darkness in Egypt, our forefathers were given the opportunity to experience this incredible ethereal light which allowed them to see all that the Egyptians had hidden from them. We are also told that if one peers into the Chanuka candles, one is able to get a glimpse of this original light as well. In any event, can you imagine what incredible healing powers that this original light must have?
Biochemically, Vitamin D is manufactured by the interaction between the skin and sunlight, plays a major role in the absorption of calcium in the digestive tract. In supplement form, it is important to know that there are two forms, one very useful, and the other potentially toxic. Always make sure that you take Vitamin D in the form of D3 (Cholcalciferol) and avoid Vitamin D2 (Ergocalciferol).
As I have implied, there are two ways to healthily get adequate Vitamin D3:
One is to try taking a 15 minute walk in the early morning, before 10 am. The morning sun is the best.
The other way is to take Vitamin D3 (Cholecalciferol) in supplement form. It is significant to emphasize that the majority of American are severely deficient in Vitamin D. Not only that, but the latest studies have shown that the outdated USDA RDA of 400 I.U.'s is grossly inadequate. Because, I unfortunately, don't get enough sun, I personally take 5000 I.U.'s of D3 in vegicap form. Though I would not necessarily recommend taking more than that (it is a fat soluable vitamin), from research I have done, I would feel comfortable recommending that dose to any adult who spends the majority of his time indoors.
Vitamin D plays a significant role in the absorption of Calcium in the digestive tract, and promotes immune function, having a major impact in the prevention of Cancer, strokes and auto-immune disorders such as MS and Alzheimers disease. Vitamin D3 deficiency can result in Obesity, Type 2 Diabetes, High Blood Pressure, Depression, Psoriasis, Fibromyalgia, Chronic Fatigue Syndrome, Kidney Stones, and Osteoporosis. As well as improving immune function, it also improves mood, reduces pain, and is neuroprotector against toxic chemicals. D3 is both a vitamin and a hormone. It acts as a vitamin to bind with calcium to promote proper absorption, for we cannot digest calcium without adequate amounts of Vitamin D3. Also it is important to note that Magnesium promotes proper Calcium utilization as well.
Again, make sure to only take D3, for D2 doesn't offer these benefits!
(Credit for major portions of this article go to my friend and colleague, Dr. Daniel Wasserman of Miami Beach)