"I believe, first of all, that the distinction between vitamin D3 and vitamin D3 sulfate really matters, and also that the distinction between vitamin D2 and vitamin D3 really matters. Vitamin D2 is the plant form of the vitamin. It works similarly to D3 with respect to calcium transport, but it cannot be sulfated. Furthermore, apparently the body is unable to produce vitamin D3 sulfate directly from unsulfated vitamin D3 19 (which implies that it produces vitamin D3 sulfate directly from cholesterol sulfate). I am not aware of any other food source besides raw milk that contains vitamin D3 in the sulfated form. So, when studies monitor either vitamin D supplements or vitamin D serum levels, they’re not getting at the crucial aspect for heart protection, which I think is the serum level of vitamin D3 sulfate.
Furthermore, I believe it is extremely likely that vitamin D3 sulfate is not the only thing that’s affected by greater sun exposure, and maybe not even the most important thing. Given that cholesterol sulfate and vitamin D3 sulfate are very similar in molecular structure, I would imagine that both molecules are produced the same way. And since vitamin D3sulfate synthesis requires sun exposure, I suspect that cholesterol sulfate synthesis may also exploit the sun’s radiation energy."
"Sulfur is also VERY important for the digestion; sulfur deficiency may well be a contributor to poor utilization of supplements.
Just a little highlights, there is a lot of info in these two links;
"Sulfur is the eighth most common element by mass in the > human body, behind oxygen, carbon, hydrogen, nitrogen, calcium, phosphorus, and potassium. The two sulfur-containing amino acids, methionine and cysteine, play essential physiological roles throughout the body. However, sulfur has been consistently overlooked in addressing the issues of nutritional deficiencies. In fact, the American Food and Drug Administration has not even assigned a minimum daily requirement (MDR) for sulfur. One consequence of sulfur's limbo nutritional status is that it is omitted from the long list of supplements that are commonly artificially added to popular foods like cereal.
Sulfur is found in a large number of foods, and, as a consequence, it is assumed that almost any diet would meet the minimum daily requirements. Excellent sources are eggs, onions, garlic, and leafy dark green vegetables like kale and broccoli. Meats, nuts, and seafood also contain sulfur. Methionine, an essential amino acid, in that we are unable to synthesize it ourselves, is found mainly in egg whites and fish. A diet high in grains like bread and cereal is likely to be deficient in sulfur. Increasingly, whole foods such as corn and soybeans are disassembled into component parts with chemical names, and then reassembled into heavily processed foods. Sulfur is lost along the way, and there is a lack of awareness that this matters."
"Sulfur is known as a healing mineral, and a sulfur deficiency often leads to pain and inflammation associated with various muscle and skeletal disorders. Sulfur plays a role in many biological processes, one of which is metabolism. Sulfur is present in insulin, the essential hormone that promotes the utilization of Sugar derived from carbohydrates for fuel in muscle and fat cells. However, my extensive literature search has led me to two mysterious molecules found in the blood stream and in many other parts of the body: vitamin D3 sulfate and cholesterol sulfate [Strott2003]. Upon exposure to the sun, the skin synthesizes vitamin D3 sulfate, a form of vitamin D that, unlike unsulfated vitamin D3, is water soluble. As a consequence, it can travel freely in the blood stream rather than being packaged up inside LDL (the so-called "bad" cholesterol) for transport [Axelsona1985]. The form of vitamin D that is present in both human milk [Lakdawala1977] and raw cow's milk [Baulch1982] is vitamin D3 sulfate (pasteurization destroys it in cow's milk, and the milk is then artificially enriched with vitamin D2, an unsulfated plant-derived form of the vitamin).
Cholesterol sulfate is also synthesized in the skin, where it forms a crucial part of the barrier that keeps out harmful bacteria and other microorganisms such as fungi [Strott2003]. Cholesterol sulfate regulates the gene for a protein called profilaggrin, by interacting like a hormone with the nuclear receptor ROR-alpha. Profilaggrin is the precursor to filaggrin, which protects the skin from invasive organisms [Sandilands2009, McGrath2008]. A deficiency in filaggrin is associated with asthma and arthritis. Therefore, cholesterol sulfate plays an important role in protection from asthma and arthritis. This explains why sulfur is a healing agent.
Like vitamin D3 sulfate, cholesterol sulfate is also water-soluble, and it too, unlike cholesterol, does not have to be packaged up inside LDL for delivery to the tissues. By the way, vitamin D3 is synthesized through a couple of simple steps from cholesterol, and its chemical structure is, as a consequence, nearly identical to that of cholesterol."
"Homocysteine is a natural substance made by the body. Homocysteine functions at a metabolic crossroad that can affect all the methyl and sulfur group metabolism of key enzymes, hormones, and vital nutrients. Many people lack the ability to break it down completely, and high homocysteine levels usually occur due to the inability to clear homocysteine because of faulty methionine pathways (mercury and lead toxicity). The result is a buildup of homocysteine in the system. When it is not completely broken down, homocysteine becomes a very dangerous substance that can exert harmful effects and increase disease-causing oxidation. When it is broken down completely, it can furnish necessary substances for other beneficial reactions in the body (methyl and sulfur groups). These necessary substances provide the fuel for vital processes like liver detoxification, adrenal gland support, neurotransmitter synthesis, and joint cartilage and bone regeneration. Homocysteine is a very dangerous substance that is harmful to the arteries, which makes it a risk factor for heart disease if it is not broken down completely.
"Homocysteine is not toxic when the pathway is functioning properly. Synergistic nutrients facilitate the homocysteine pathway, preventing toxic levels of homocysteine from accumulating, and make it possible for a functioning pathway to provide necessary methyl groups and sulfur groups for a myriad of biochemical reactions, especially those needed for detoxification and joint and cartilage repair. Nutrients which facilitate the methionine pathway and reduce homocysteine include betaine, dimethylglycine, and vitamins B6, B12, folic acid, niacinamide, choline, betaine, dimethylglycine, magnesium, and molybdenum. Homocysteine is recycled to methionine in the presence of B12, folic acid, and methyl donors such as choline or betaine (trimethylglycine). B6 (pyridoxyl-5-phosphate is the active form) and magnesium help convert homocysteine to cysteine. Molybdenum is an essential trace mineral necessary to convert the toxic sulfite molecule to the important sulfate molecule needed for many biochemical reactions." http://www.tuberose.com/Sulphur_and_Mercury.html