I have been taking vitamin A for a few years now. The first thing that I noticed was that after a few months my coarse, dry, sandpaper elbows that I wanted to hide from the world became normal except for a very small area. I also noticed that I do not need any BEANO for eating raw onion or garlic like I used to. My intestines can now tolerate my mother-in-law's heavy on the garlic cooking. This was unexpected but I now save money on not having to buy those tablets. I guess because the intestines have endothelial tissue and vitamin A helps endothelial tissue, this is why it helped. Also, my extremely oily hair can now go without having to wash it everyday. Vitamin A is supposed to help dry skin be less oily but at the same time dry up oily skin. It works for me. Finally, I am not sure but I highly suspect that vitamin A may have helped me to cut my thyroid drug dose in half. Bear in mind, that one should always take D3 and K2 along with vitamin A to lower the likelihood of toxicity. See Vitamin K2 and the Calcium Paradox to see how they work synergistically. I first started taking D3 which stopped me from developing Asthma. A year later I began the vitamin A. Later when I added K2 and upped my D3( because of still being deficient according to a blood test) I got even better results from the vitamin A. Doctors now are usually willing to test vitamin D status but may prescribe D2 not D3 which is not as good. There is also a test for vitamin A if you are concerned about toxicity. In most states you can order it from an online lab. I believe it is called the retinol test