Originally Posted by caseymyhorserocks
Also, you may get people saying corn oil, or some other oil, but please do NOT use it! Although it is great for getting a shine on the coat and gaining weight on horses, the health risks out-lie the benefits. Corn oil contains almost all Omega 6 fatty acids, which are pro inflammatory. Then the oil and pro inflammatorys often affects the horses joints, skin, or lungs.
That's interesting as it is extremely common to feed vegetable oil to horses for weight gain over here and I have never heard of a problem. I think most owners I know whould suggest feeding oil and regard it as a healthy thing to do.
Personally for a shiny coat and great hooves I would feed linseed (micronised) and balanced vitamins / minerals.
If your horse is grey though it wont really shine like a dark horse.