Although no medical uses for MSM have been approved by any government, a variety of health benefits have been claimed and studied. Stanley W. Jacob reported having administered MSM to over 18,000 patients with a variety of ailments; he co-authored a book promoting MSM with a variety of claims, including a utility as a natural source of "biologically active sulfur," suggesting that people are deficient in such forms of sulfur in their dietary intake. There is no Dietary Reference Intake (DRI) or Daily Value established for sulfur but notable dietary sources include cruciferous vegetables, garlic, onions, asafoetida, legumes, nuts, seeds, plant milk, animal milk and eggs (whites and yolks).