The most controversial certification is the K, a plain letter K found on products asserted to be kosher. A letter of the alphabet cannot be trademarked, so any manufacturer can put a K on a product, even without any supervision at all. For example, Jell-O brand gelatin puts a K on its product, even though every reliable Orthodox authority agrees that Jell-O is not kosher. On the other hand, some very reliable rabbis will certify products without having a trademark to offer, and their certifications will also have only a "K." Most other kosher certification marks are trademarked and cannot legally be used without the permission of the certifying organization. The certifying organization assures you that the product is kosher according to their standards, but standards vary.
The location of the tissue determines its metabolic profile: visceral fat is located within the abdominal wall (., beneath the wall of abdominal muscle) whereas " subcutaneous fat " is located beneath the skin (and includes fat that is located in the abdominal area beneath the skin but above the abdominal muscle wall). Visceral fat was recently discovered to be a significant producer of signaling chemicals (., hormones ), among which several are involved in inflammatory tissue responses. One of these is resistin which has been linked to obesity, insulin resistance , and Type 2 diabetes. This latter result is currently controversial, and there have been reputable studies supporting all sides on the issue.