Vitamin E is a fat-soluble vitamin found in corn, soy, sunflower, safflower and wheat germ oils, as well as nuts and fortified grain products. It acts as an anti-oxidant, preventing cell damage caused by oxidation. It can help reduce scarring from injuries and plays and important role in the growth of smooth muscles. Most people maintain acceptable levels of vitamin E via the food they eat. This means that low vitamin E serum levels usually indicate a serious underlying health problem that is preventing the vitamin from being used properly.

A deficiency in this vitamin is relatively rare and is almost never caused by a poor diet, since almost all plant oils, vegetables and meats contain at least a little bit of vitamin E. People with cystic fibrosis, liver disease, pancreatic insufficiency, Chron disease or other problems that prevent them from absorbing fats correctly are often unable to absorb vitamin E as well. Low serum levels are also present in some people with fat metabolism problems.

Vitamin E serum testing can help detect these types of diseases and is recommended for people who show signs of poor motor control or loss of sensation in the skin. In adults, the test should ideally show levels of 5.5 to 17 milligrams per liter. Levels below 3 milligrams indicate a serious deficiency, while levels above 40 milligrams indicate possible overdose.

To get an accurate result, patients should FAST for 10 hours before the test, avoiding all food and any beverages other than water.