Vitamin E in Breast Cancer Risk and Treatment

Can Vitamin E Lower Breast Cancer Risk or Improve Treatment?

Bottle of vitamin E soft gells, close-up
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Can vitamin E lower the risk of breast cancer or reduce the risk of recurrence? The answer isn't a simple yes or no.  And it totally matters what type of vitamin E compounds you are talking about, as they may have opposite effects - probably why so much of the evidence to date has been "equivocal."

Vitamin E Definition

Vitamin E is a fat-soluble vitamin which has antioxidant properties. There are 2 basic kinds of vitamins we see routinely.

Some are water-soluble, such as vitamin C. If you get too much of these vitamins you simply urinate them out - but they're hard to store as well. You need to get these in your diet on a routine basis.

Fat-soluble vitamins can be stored in the body, and if you get too much, you can store too much.  Storage can be good if you don't get enough in your diet for a period of time, but our bodies weren't designed to store massive amounts of these vitamins as our kidneys don't get rid of them as they do with water-soluble vitamins.

Being fat soluble can also tell you about how they are absorbed. Water-soluble vitamins are best absorbed in a watery diet and fat soluble vitamins are best absorbed in a fatty diet.  Vitamin E taken on an empty stomach doesn't tend to get absorbed.  Your best bet is to take vitamin E or eat foods with vitamin E at the same time as a meal that has at least some fat in it for best absorption.

  Or, instead, you could take it along with vitamin D or fish oil.  But first, it's important to decide if you want to take vitamin E or eat a diet high in this vitamin.  Let's review the uses of vitamin E as well as what we know about research on vitamin E and breast cancer.

Primary Use of Vitamin E

The only medical condition for which vitamin E is definitely indicated is vitamin E deficiency, a rare condition that results in impaired nerve function.

Vitamin E Deficiency

Vitamin E deficiency is most often seen in people with medical conditions causing problems with fat absorption, such as cystic fibrosis, Crohn's disease, and among people who eat extremely low-fat diets. Otherwise, there is really no such thing as dietary vitamin E deficiency.  A simple blood test can be done to check the blood level of vitamin E.

Tocopherols - Types of Vitamin E

There are several types of vitamin E and it is important to know the differences. These include:

  • Alpha-tocopherol
  • Gamma tocopherol
  • Tocotrienols

It's important to separate out these different types of tocopherols when discussing benefits, as some supplements contain only certain tocopherols, and different tocopherols can have different and even opposite effects in the body.

Food sources of vitamin E are mostly gamma tocopherol and tocotrienols.

How Vitamin E Works

Vitamin E's main function in the body is to enable the proper functioning of nerves and muscles. Part of the tocopherol molecule is well-suited to enable it to penetrate cell walls, and another part can give up a hydrogen atom to neutralize harmful free radicals inside of cells.

Sources of Vitamin E

Dietary sources of vitamin E include many types of vegetable oils such as wheat germ oil, sunflower, peanut and soybean oils. It is found in many seeds, grains, and meats. Generic vitamin supplements (gel caps), as an oil, and as a food additive.

Excess Vitamin E

High doses of vitamin E can reduce the ability of platelets to stick together, and therefore could in increase the risk of bleeding in people on blood thinners.  Symptom wise high doses can cause nausea and diarrhea. Some studies also suggest a risk of heart problems in people who take high doses of vitamin E.

Vitamin E Cautions in Breast Cancer

Before discussing any possible benefits of vitamin E - either dietary or in supplement form - in breast cancer, it's important to bring up a caution. Due to its effective as an antioxidant, vitamin E may actually cancel out the benefits of chemotherapy.  In other words, you don't want to protect your cancer cells from oxidative damage from chemotherapy or radiation therapy.  This is one of the ways in which these treatments work to kill cancer. This is a reason why several vitamin and mineral compounds may interfere with cancer treatment.

Vitamin E and Breast Cancer Prevention

Vitamin E has been studied quite extensively for its possible role in cancer prevention.  Some types of vitamin E are effective antioxidants, meaning that they can reduce the activity of harmful free radical activity in the body. Free radicals are charged compounds that are produced in a reaction including oxygen in the body, and you may hear it referred to as "oxidative stress" for that reason.  This is also where the term antioxidant is derived. Free radicals are thought to lead to cancer by directly damaging DNA.

Studies on women have found that a diet high in vitamin E is associated with a significantly lower risk of developing breast cancer. Studies with supplements, however, failed to find a very significant reduction in risk with the exception of people who seem to have a hereditary predisposition to breast cancer. It's thought that perhaps the alpha -tocopherols found in supplements does not have the effect of dietary vitamin E which contains gamma tocopherol and other forms of vitamin E.

What should you do? Since a diet rich in vitamin E during adolescence was associated with a significantly lower risk of breast cancer, and this included other nutrients as well, it appears that as a country we should be encouraging healthier choices for our children.

For those with a family history of breast cancer, especially premenopausal breast cancer, dietary vitamin E was also noted to pack an extra punch.

Since vitamin E supplements of alpha-tocopherol did not appear to be associated with much of a risk reduction at all, it's important to consider other reasons you may wish to take a supplement.

Vitamin E and Breast Cancer Treatment

It's important to again restate that it's important to talk to your oncologist before taking any supplement during cancer treatment.  If you wish, you can talk to your doctor and explore the links at the bottom of this article to the original studies which give much more information in order to make an informed decision.

As with breast cancer prevention, supplements of vitamin E containing alpha-tocopherol do not appear to have much effect on breast cancer.

Tocotrienols, however, a dietary vitamin E compound, do.  In lab studies, tocotrienols appeared to accentuate the effect of tamoxifen on estrogen receptor positive breast cancer cells and worked to induce programmed cell death (apoptosis) of breast cancer cells.

Summary of Vitamin E and Breast Cancer

With regards to breast cancer prevention, dietary sources of vitamin E are associated with a significant reduction in risk, while supplements are not.  This could be due to the type of compounds present, with gamma tocopherol being more common in dietary sources while alpha tocopherol is more common in supplements

For women with breast cancer, again supplements of vitamin E do not appear to provide any benefit.  Lab studies, however, suggest that dietary vitamin E may have a benefit at least for women with estrogen receptor-positive tumors.

To learn more, check out these cancer-preventing foods and these cancer-fighting foods which may make a difference both in the risk and treatment of cancer.


Frazier, A., Li, L., Cho, E., Willett, W., and G. Colditz. Adolescent diet and risk of breast cancer. Cancer Causes and Control. 2004. 15(1):73-82.

Khallouki, F., de Medina, P., Caze-Subra, S. Molecular and Biochemical Analysis of the Estrogenic and Proliferative Properties of Vitamin E Compounds. Frontiers in Oncology. 2016. 5:287.

Nesaretnam, K., Meganathan, P., Veerasenan, S., and K. Selvaduray. Tocotrienols and breast cancer: the evidence to date. Genes and Nutrition. 2012. 7(1):3-9.

Smolarek, A., and N. Suh. Chemopreventive activity of vitamin E in breast cancer: a focus on y- and d-tocopherol. Nutrients. 2011. 3(11):962-86.

Tamimi, R., Hankinson, S., Campos, H. et al. Plasma carotenoids, retinol, and tocopherols and risk of breast cancer. American Journal of Epidemiology. 2005. 161(2):153-60.

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