Vitamin E (Tocopherol) Test

A vitamin E test measures the amount of vitamin E in your blood. Vitamin E (also known as tocopherol or alpha-tocopherol) is a nutrient that is found in every cell of your body. It helps your nerves and muscles work well, prevents blood clots, and boosts your immune system so it can fight off infections from germs.

Vitamin E is a type of antioxidant, which means that it protects cells from damage. But if you have too little or too much vitamin E in your body, it can cause serious health problems. Most people get the right amount of vitamin E from foods, including vegetable oils, nuts, seeds, avocados, and green, leafy vegetables.

Vitamin E is also added to foods such as certain cereals, fruit juices, and margarine. The amount of vitamin E you get from foods doesn't cause harmfully high levels of vitamin E in your body. High levels usually happen from taking too many vitamin E supplements.

Low levels are often caused by digestive diseases, including malabsorption disorders that make it difficult for your body to digest fat. Your body needs fat to absorb vitamin E.

Why this test is done

You may need a vitamin E test if you have symptoms of vitamin E deficiency (low levels of vitamin E) or vitamin E excess (high levels of vitamin E).

Symptoms of a vitamin E deficiency often involve damage to the nerves and muscles. They include:

• Muscle weakness
• Loss of feeling in your arms and legs
• Problems walking and controlling your body movements
• Vision problems

Vitamin E deficiency is very uncommon in healthy people. Most of the time, it's caused by conditions that prevent your body from properly absorbing vitamin E, including:

• Crohn's disease, a chronic (long-lasting) disease that causes inflammation in your digestive tract
• Liver disease
• Cystic fibrosis, a disease of the mucus and sweat glands that's inherited (passed down through families)
• Celiac disease, a chronic digestive and immune disorder that damages your small intestine
• Pancreatitis, inflammation of the pancreas
• Certain genetic disorders, including ataxia with vitamin E deficiency and abetalipoproteinemia (a very uncommon inherited disorder)

Eating an extremely low-fat diet can also lead to a vitamin E deficiency.

Symptoms of too much vitamin E include:

• Diarrhea
• Nausea
• Fatigue
• Muscle weakness

Vitamin E excess is uncommon. It usually happens from taking too many vitamin E supplements. Without treatment, too much vitamin E can increase your risk of bleeding, including bleeding in the brain, called a hemorrhagic stroke.

How to prepare

You will probably need to fast (not eat or drink) for 12-14 hours before the test.

Sample type

Blood

Other names for this test

tocopherol test, alpha-tocopherol test, vitamin E serum test