Vitamin E: what it is, what it tells you and when it’s tested

Vitamin E protects your cell membranes from damage by oxygen. Your nerves, muscles and red blood cells need it most. It dissolves in fat, and the blood test measures its main form, alpha-tocopherol.

When it’s tested

Doctors order it when they suspect a shortage: with conditions that absorb fat poorly, such as cystic fibrosis, pancreas or bile duct disease, coeliac disease, or after weight-loss surgery. They also order it for balance problems and tingling with no clear cause.

It is not a routine test for people who feel well. A shortage is rare, and the value changes a lot with cholesterol and triglycerides, so on its own it says little.

That is why Rosa does not test it. Instead it looks at cholesterol and triglycerides, which you need to read vitamin E and which matter far more for your heart, and at vitamin D, another fat-soluble vitamin.

What it tells you, and what it does not

A low value is useful: it says your body is probably short of it.

A normal or high value says less. Vitamin E travels with the fats in your blood: if your cholesterol and triglycerides are high, it rises too, without your tissues having more. That is why some labs report it against cholesterol.

That is why it is read together with other tests:

• Total cholesterol: When it is high, vitamin E rises with it
• Triglycerides: They also carry vitamin E in your blood
• Vitamin A: Short with the same conditions that absorb fat poorly
• Vitamin K: Vitamin K helps your blood clot, and high-dose vitamin E favours bleeding

Normal vitamin E levels

The lab decides what is normal. Some lab reports give 5 to 18 mg/L in adults, the same for men and women. Others print a slightly higher upper limit. In children the limits are lower.

Some write µg/mL, which gives the same number. Others use µmol/L, with higher numbers. The range printed next to your result is what counts.

The blood test is done fasting, and the sample must be kept out of the light.

What your result means

Find the row for your result, in mg/L or µg/mL. If it is high, look at your cholesterol and triglycerides too.

• Below 5: Low. Your body may be short of it. This is rare, and usually a bowel, pancreas or liver problem that stops fat being absorbed well is behind it. Talk to your doctor: they look for the cause of the poor absorption.
• 5 to 18: Normal. Your body has enough. Nothing to do.
• Above 18: High. It often comes from a supplement. High cholesterol and triglycerides raise it too, because vitamin E travels with the fats in your blood. Talk to your doctor, especially if you take blood thinners. Look at your cholesterol and triglycerides too.

If your vitamin E is low or high

• Low vitamin E: Rare. Usually a condition that makes fat poorly absorbed is behind it.
• High vitamin E: Often from supplements or high cholesterol. At high doses it can favour bleeding.

Who is at risk of a vitamin E shortage

With a normal diet it is rare. It is more common in these cases:

• Conditions that absorb fat poorly: Cystic fibrosis, pancreas disease, coeliac disease, Crohn’s disease.
• Liver and bile duct disease: If bile does not reach the bowel, fats and their vitamins are poorly absorbed.
• Weight-loss surgery: After some operations less fat is absorbed.
• Rare inherited conditions: Some genetic forms stop the body from using it well.

Symptoms of a vitamin E shortage

A shortage develops slowly and mainly affects the nerves. It can cause:

• Loss of balance and coordination
• Tingling and less feeling in your hands and feet
• Muscle weakness
• Vision problems
• Anaemia, because red blood cells break more easily

If you have these symptoms, talk to your doctor.

Vitamin E supplements: what studies say

For years vitamin E was thought to protect the heart and prevent cancer. Studies in large numbers of people did not confirm it.

In fact, at high doses supplements were linked to higher mortality, and in healthy men to more prostate cancer. At high doses, or with blood thinners such as warfarin, they also raise the risk of bleeding.

If you are not short of it, taking it does not help. If you take blood thinners, do not start supplements without talking to your doctor.

Where it is found: what to eat

Vitamin E is found mostly in fatty plant foods. For example:

• Vegetable oils: wheat germ, sunflower and extra virgin olive oil
• Nuts: almonds and hazelnuts
• Seeds, such as sunflower seeds
• Avocado and leafy greens

A varied diet is usually enough. Ask your doctor before taking supplements.

What can skew the result

A few things change the value without changing your stores.

• High cholesterol and triglycerides: They raise vitamin E in your blood. That is why your doctor reads them together.
• A recent meal: Eating fat before the blood test can raise it. That is why it is done fasting.
• Supplements: Say so before the blood draw, even if you take them only now and then.
• A tube left in the light: Vitamin E breaks down in light. The lab protects the sample.

When to worry

Talk to your doctor if:

• Your vitamin E is below the range on your report.
• You have loss of balance, tingling or muscle weakness with no clear cause.
• You take vitamin E supplements as well as blood thinners or antiplatelet medicines.
• You bruise easily or often have nosebleeds or bleeding gums.
• You have blood in your urine or black stools, vomit blood or get a sudden severe headache: call 112 or go to the emergency department.

Frequently asked questions

What does vitamin E do? It protects your cell membranes from damage by oxygen. Your nerves, muscles and red blood cells need it most.

What are normal vitamin E levels? Some lab reports give 5 to 18 mg/L in adults; others print a slightly higher upper limit. The range printed on your own report is what counts.

Which foods contain vitamin E? Vegetable oils such as wheat germ, sunflower and extra virgin olive oil, almonds, hazelnuts, sunflower seeds, avocado and leafy greens.

What does high vitamin E mean? It often comes from a supplement, or from high cholesterol and triglycerides, which carry it. At high doses it can favour bleeding, especially with blood thinners. Talk to your doctor.

Do vitamin E supplements help? Only if you are short of it, which is rare. In studies they did not protect the heart or prevent cancer, and at high doses they can do harm. Decide with your doctor.

Does Rosa test vitamin E? No. Rosa measures cholesterol, triglycerides and vitamin D. If your doctor wants vitamin E, they order it separately.

Sources

• ASST Grande Ospedale Metropolitano Niguarda, laboratory test catalogue: vitamin E, reference values. Catalogo esami Niguarda
• Traber, vitamin E inadequacy in humans: causes and consequences. Advances in Nutrition, 2014. PMID 25469382
• Miller and colleagues, meta-analysis: high-dosage vitamin E supplementation may increase all-cause mortality. Annals of Internal Medicine, 2005. PMID 15537682
• Klein and colleagues, vitamin E and the risk of prostate cancer: the Selenium and Vitamin E Cancer Prevention Trial (SELECT). JAMA, 2011. PMID 21990298
• MSD Manual, professional edition (Italian): vitamin E toxicity. Manuale MSD