What does deficiency in fat cause?

A deficiency in fat can cause many problems. Having a fat deficiency can cause you to be deficient in the fat soluble vitamins (A, D, E and K) as fat is required for them to be absorbed by the intestines. So it can cause those vitamin deficiency symptoms as well as fat deficiency symptoms.

I wasn't able to quickly find general fat deficiency symptoms, only essential fatty acid deficiency symptoms. So you can read all about that on a google search.

If you're wanting to know if fats are really that important to your health, then absolutely. They serve many essential functions in the body. They're a major component of every cell membrane in the body.

If you're having health problems and you're wondering if it's due to a fat deficiency then you should consult with a doctor.