Vitamin E in a nutshell:
Vitamin E is a potent antioxidants that protects your body against free radicals which may be involved in degenerative diseases, cancer and aging.Best source of vitamin E for Juicers:
Spinach, watercress, asparagus, carrots & tomatoes.
Vitamin E is not just a single chemical compound that is vital to human health. It's actually a group of eight chemical compounds with very similar chemical structures.
Alternative Names:
Vitamin E; alpha-tocopherol; beta-tocopherol; gamma-tocopherol; delta-tocopherol; alpha-tocotrienol; beta-tocotrienol; gamma-tocotrienol; delta-tocotrienol.
What Is Vitamin E?
Plants make vitamin E to protect their seeds. They also use vitamin E to deal with the effects of drought and exposure to salt. Vitamin E is also abundant in eggs, in which it helps prevent decay before the egg can be hatched.
Four of the forms of vitamin E are chemicals known as tocopherols, and four of the forms of vitamin E are chemicals known as tocotrienols. The tocopherols and tocotrienols both exist in alpha-, beta-, gamma-, and delta- forms.
There are only slight chemical differences among the eight forms of vitamin E. Tocopherols are naturally more abundant in the body than tocotrienols. An alpha- form is always more potent for detoxifying free radicals than a beta- form, a beta- form is always more reactive than a gamma- form, and a gamma-form is always more potent than a delta- form. A tocopherol acts a little more like vitamin C and a tocotrienol acts a little more like unsaturated fat. The human body can't convert one form of vitamin E into another.
The main thing most of us need to know about the difference between tocopherols and tocotrienols is that tocopherols are essential for maintaining health, while tocotrienols seem to be more important for supporting recovery from diseases. The two forms of vitamin E that are best understood by science are alpha-tocopherol and gamma-tocopherol.
What Does Alpha-Tocopherol Do in the Human Body?
The two kinds of vitamin E with which scientists are most familiar are alpha-tocopherol and gamma-tocopherol. There is a lot more alpha-tocopherol than any other form of vitamin E in the body, and gamma-tocopherol comes in second place.
The function of alpha-tocopherol in the body is to prevent against free radical damage. Free radicals of oxygen form when the body is exposed to radiation (including UV rays of the sun falling on the skin) or toxins, or when the body uses a lot of oxygen to burn sugar. Both athletes and diabetics can experience free radical damage from excessive burning of glucose sugar as metabolic fuel.
Because alpha-tocopherol is soluble in fat and the linings of cells are made mostly of fatty acids, alpha-tocopherol is especially helpful for preventing the entry of free radicals into a cell. Alpha-tocopherol protects low-density lipoprotein (LDL) cholesterol from free radicals that change it into forms that are “sticky” in the linings of blood vessels. It helps cells send signals to each other. It also relaxes blood vessels so more blood can flow at lower pressure by preventing the activation of platelet-activating factor, which is essential for the formation of blood clots.
What Does Gamma-Tocopherol Do in the Human Body?
The form of vitamin E known as gamma-tocopherol seems to “hitch a ride” when the body absorbs alpha-tocopherol from food. It is not retained in the body as long as alpha-tocopherol, and increasing consumption of alpha-tocopherol reduces the amount of gamma-tocopherol the body can assimilate from digested food. The human body is never completely depleted of alpha-tocopherol (it will just stop using it before it destroys its entire supply), but it can become completely depleted of gamma-tocopherol.
Like alpha-tocopherol, gamma-tocopherol is a potent antioxidant, but with one important difference. Alpha-tocopherol neutralizes damaging free radicals of oxygen. Gamma-tocopherol neutralizes damaging free radicals of nitrogen. Scientists used to say that gamma-tocopherol was not as important as alpha-tocopherol because it only neutralizes 10% as many free radicals of oxygen. This was before scientists realized that free radicals of nitrogen also cause cell damage that can lead to atherosclerosis and cancer.
Both kinds of vitamin E can eliminate up to 99.99% of the free radicals formed when the body absorbs toxic substances. The difference is that the prevent the formation of different kinds of free radicals.
Are You at Risk of Vitamin E Deficiency?
The only kind of vitamin E for which the scientific community has established a recommended daily intake is alpha-tocopherol. It only takes 15 IU (a little under 7 mg) of alpha-tocopherol each day to prevent vitamin E deficiency diseases. That's just 15% of the amount of alpha-tocopherol in a 100 IU capsule or 7.5% of a 200 IU capsule. It's less than 1% of the alpha-tocopherol some people take to support recovery from diabetes or vascular disease. But it's more alpha-tocopherol than the average diet, even the average low-fat “healthy” diet, provides on a daily basis.
Moreover, most of the vitamin E in the food we eat is never absorbed into our bodies. It simply passes out of the body with fecal waste. People who have a condition known as short-bowel syndrome, or who have intestinal ulcers or other intestinal problems, or who cannot digest fat, are at special risk of not getting enough vitamin E.
People whose bodies cannot absorb vitamin E (such as people who have cystic fibrosis or who have gallstones) or people whose bodies cannot use vitamin E or who simply don't get any vitamin E at all in their diets usually develop diseases of the central nervous system. One symptom of vitamin E deficiency is ataxia, a condition of poor balance and coordination. There may also be loss of hearing or the sense of touch or slurred speech.
Another symptom of milder vitamin E deficiency is hardening of the arteries—but that symptom may not be noticed until it is too late to anything to correct it.
How You Can Be Sure You Get Enough Vitamin E?
Sometimes the best way to make sure you are getting enough vitamin E isn't to take more vitamin E. It's to take more vitamin C!
Vitamin C recharges vitamin E after it has neutralized free radicals. It is not necessary to take a megadose of vitamin C to protect your vitamin E. Five servings of fruits and vegetables a day or a 100 mg vitamin C supplement every day is enough to recharge your vitamin E.
On the other hand, it may help to lower your consumption of fat. One of the most important tasks of vitamin E is to prevent the oxidation (sometimes called rancidity) of the polyunsaturated, relatively healthy fats we are told to eat instead of trans- fat and saturated fat. If you eat lots of fat, you need more vitamin E, possibly a lot more.
In setting the recommended daily intake of vitamin E, scientists actually did not make an in-depth investigation of how much vitamin E the body needs. They just assumed that the average person was not deficient and set average daily intake as the recommended daily intake. The recommended dietary intake is a minimum for good health. These figures are averages—you don't have to get exactly this amount of alpha-tocopherol each and every day.
- Infants need 4 mg or 10 IU of alpha-tocopherol daily.
- Children aged 1 to 3 need 5 mg or 12 IU of alpha-tocopherol daily.
- Children aged 4 to 8 need 6 mg or 13 IU of alpha-tocopherol daily.
- Children aged 9 to 13 need 7 mg or 15 IU of alpha-tocopherol daily.
- Older teens and adults up to the age of 50 also need 7 mg or 15 IU of alpha-tocopherol daily, but adults 50 and over may need as much as 15 mg or 32 IU per day.
Where to get vitamin e
Can you get all the vitamin E you need from food? Here are examples of the alpha-tocopherol content of common foods.
- A 3-1/2 oz or 100 g serving of Kashi Heart-to-Heart, General Mills Multi-Grain Cheerios, Kellogg's All-Bran, and General Mills Total all contain about 45 mg or 100 IU of alpha-tocopherol. These cereals add synthetic vitamin E.
- A 3-1/2 oz or 100 g serving of sunflower seeds, almonds, or almond butter contain about 36 mg or 80 IU of alpha-tocopherol.
- A tablespoon (15 ml) of wheatgerm oil, almond oil, or grapeseed oil (assuming it's fresh) contains about 15 mg or 33 IU of alpha-tocopherol.
- A small package of potato chips (crisps) typically contains about 11 mg or 24 IU of vitamin E, all of it synthetic, used as preservative. If the chips are stale, the vitamin E has already been used up fighting decay.
- A 3-1/2 oz or 100 g serving of either raw or roasted peanuts contains about 8 mg or 15 IU of vitamin E. Roasting the nuts actually concentrates the vitamin E.
- A 3-1/2 oz or 100 g serving of either dried apricots or pitted green olives contains about 4 mg or 8 IU of vitamin E.
There is also significant vitamin E, usually 2 to 5 mg or 3 to 7 IU of vitamin E in servings of avocados, most kinds of fresh berries, spirulina, kelp, nori, sweet peppers and tomatoes (especially dried sweet peppers and tomatoes), turnip greens, dandelion greens, and broccoli.
There is no recommended daily intake of gamma-tocopherol, but it is most abundant in pecans, pistachios, flaxseed, buckwheat, edamame, blue corn, quinoa, and tuna (even canned tuna). Because North American food manufacturers use gamma-tocopherol as a food preservative, especially in snack foods and pie crusts, most Americans and Canadians actually get more gamma-tocopherol in their diets than alpha-tocopherol. If you don't eat prepared foods, then be sure to eat consume some of the natural sources of gamma-tocopherol several times a week.
Do You Need to Take a Vitamin E Supplement?
If you make a point of eating nuts and seeds and vegetables, if you don't eat too much fat, and if you have a healthy digestive tract, then you can plan on getting all of your vitamin E from food. The reality is, however, that most of us don't eat the healthy food we need and we don't get enough vitamin E for optimum health. But that doesn't mean it's necessary or wise to take huge amounts of supplemental vitamin E.
Most vitamin E supplements contain only synthetic alpha-tocopherol. A single 100 IU (45 mg) vitamin E capsule every day will provide considerably more alpha-tocopherol than your body needs to fight deficiency. It's probably even enough if you have one of the diseases discussed above that interferes with your body's ability to absorb vitamin E. And it's not so much that it interferes with your body's ability to absorb gamma-tocopherol and the other forms of vitamin E.
Taking much more than 100 mg of vitamin E a day, however, tends to get mixed results. One study will find that taking 300 mg of vitamin E (as alpha-tocopherol) a day reduces the risk of heart disease and another will find that it increases it. One study will find that taking 450 mg (again, as alpha-tocopherol) of vitamin E a day reduces the risk of cancer and another will find that it increases it.
The problem with taking a lot of alpha-tocopherol is that it interferes with your body's ability to absorb other forms of vitamin E. Alpha-tocopherol is needed to fight the production of free radicals of oxygen, but gamma-tocopherol is needed to fight the production of free radicals of nitrogen. It will not be until May of 2012 that there will be major scientific announcements on the uses of the other six forms of vitamin E, but it's safe to assume that they are important.
The best way to take supplemental vitamin E is to find a supplement that provides all eight forms of vitamin E—and no more than 450 IU or 225 mg of alpha-tocopherol. Taking a higher dosage of just one form of vitamin E may cause as many health problems as it relieves.
Frequently Asked Questions About Vitamin E Supplements
Q. Do vitamin E supplements cause bleeding?
A. Yes. They can if taken in excessive doses. Taking too much vitamin E can cause bleeding and bruising. Adults should not take more than 1,000 IU of vitamin E a day, teens and children over 6 more than 600 IU a day, and children between ages 1 and 6 more than 200 IU day except under a doctor's supervision for a medical condition.
Q. Is there a difference in the ways natural vitamin E and synthetic vitamin E work in the body?
A. Yes. Natural vitamin E is involved in more processes than synthetic vitamin E, but synthetic vitamin E is more potent than natural vitamin E. Nutritionists count 450 mg of synthetic vitamin E as 1,000 IU but count 670 mg of natural vitamin E as 1,000 IU.
Q. Does alpha-tocopherol kill cancer cells?
A. No. It's alpha-tocopheryl succinate that kills cancer cells in the test tube. The problem with using alpha-tocopheryl succinate to prevent cancer is that the body does not absorb it.
Q. Does Ester-E ™ deliver more vitamin E to the body than regular vitamin E?
A. Ester-E ™, which is also known as alpha-tocopheryl phosphate, does not deliver more vitamin E to tissues than any other vitamin E supplement.
Q. Does taking vitamin E extend life?
A. No. Experiments in which volunteers took up to 5,500 IU of vitamin E a day did not find that people lived longer if they took vitamin E. Taking just 100 IU of vitamin E every day, however, may prevent painful nerve problems that are caused by vitamin E deficiency. Avoiding those problems is the main reason to take vitamin E.
Q. If the body only needs 15 IU a day, why do you recommend taking 100 IU in supplements?
A. Not all the vitamin E in the diet or in supplements is actually absorbed by the body.
Q. Do any medications increase the need for vitamin E?
A. Yes. Many medications for lowering cholesterol and treating rheumatoid arthritis interfere with the body's ability to absorb vitamin E. Seizure medications generate free radicals that are neutralized by vitamin E, causing vitamin E concentrations in the bloodstream to fall. People who take these kinds of medications may need supplemental vitamin E.
On the other hand, too much vitamin E can cause thinning of the blood. Ask your doctor or pharmacist about possible drug interactions before taking supplemental vitamin E if you take warfarin (Coumadin) or clopidrogel (Plavix).
Q. What's the kind of vitamin E that may prevent cancer?
A. The tocotrienols may play a role in cancer prevention and treatment. Here is an overview of what is known and not yet known about using them for cancer.
- Researchers at the Moffitt Cancer Center are studying the safety of using delta-tocotrienol as a treatment for pancreatic cancer.
- Researchers at Texas Woman's University have found that a combination of Lipitor and gamma-tocotrienol slows the rate at which aggressive strains of estrogen-sensitive breast cancer grow in the test tube. It's not yet known whether gamma-tocotrienol will have the same effect in a woman's body.
- One study found that gamma-tocotrienol slowed the growth of prostate cancer cells in the lab. However, another study found that alpha-tocopherol (in high doses) increased the growth of prostate cancer.
Q. What about vitamin E for diabetes?
A. It is specifically the tocotrienols that seem to slow the progression of cardiovascular complications of diabetes. Safety testing is still underway.
Q. Can vitamin E protect against the effects of radiation exposure, like radioactive iodine?
A. Actually, vitamin E offers better protection against radiation exposure than radioactive iodine, because vitamin E acts in every tissue in the body, not just the thyroid. However, it is gamma-tocotrienol and delta-tocotrienol that are protective against gamma radiation. Other forms of vitamin E are not.
Q. Are tocotrienols potentially toxic?
A. The Japanese National Institutes of Health have found that doses of tocotrienols in the range of 5000 to 6000 mg a day (5 to 6 grams a day) had no adverse effects. This is probably much more than the body needs for any health purpose, so tocotrienols, unlike alpha-tocopherol, are probably essentially non-toxic at all levels of consumption that produce other health benefits.