Most oxygen enters the starfish via diffusion into the tube feet (with the water vascular system), or the papulae (small sacs covering the upper body surface). Reproduce alone, or with a mate: Sea stars are capable of both sexual and asexual reproduction. Individual sea stars are male or female.
Specifically for keratosis pilaris, I would make extra certain that you are not eating foods with new-fangled vegetable oils such as corn, sunflower, vegetable a.k.a. soybean, grape seed, cottonseed AND canola oils. These non-traditional vegetable oils are packed with super unstable PUFAs (poly-unsaturated fatty acids).
Vitamins containing nickel. Various food items and drinks can aggravate nickel dermatitis even though the nickel content of these foods may be low. These include beer, wine (in particular, red wine), herring, mackerel, tuna, tomato, onion, carrot, and certain fruits, in particular, apples and citrus fruits (juice).