Vitamin E is an essential fat-soluble vitamin that plays a crucial role in keeping our body healthy.
While the vitamin has many functions within the body, its activity as an antioxidant is particularly notable.
This article examines the health benefits of vitamin E, the best food sources, and how natural food sources compare to supplements.
What Is Vitamin E?
Vitamin E is a collection of eight fat-soluble vitamins that act as antioxidants in the body.
Of these eight different forms of vitamin E, four belong to a group called tocopherols, and four are known as tocotrienols (1).
Firstly, the four tocopherols include;
Secondly, the four forms of tocotrienols are;
In humans, the most important of these compounds is alpha-Tocopherol because it has the best digestibility and absorption rate (2).
Despite this, it is gamma-tocopherol that is the most prevalent form of vitamin E in the American diet (3).
This fact is largely because soybean oil contains gamma-tocopherol, and this vegetable oil contributes a significant amount of calories to the average diet.
Scientifically, the vitamin E tocopherols are the most widely researched since they have a higher prevalence.
However, ongoing studies are examining the potential health benefits of tocotrienols (4).
Recommended Daily Allowance
The recommended daily allowance (RDA) for vitamin E depends on age.
As shown in the table below, the intake requirements rise with age and breastfeeding mothers have a greater need for the vitamin (1);
< 6 months
4 mg (6 IU)
7 - 12 months
5 mg (7.5 IU)
1 - 3 years
6 mg (9 IU)
4 - 8 years
7 mg (10.4 IU)
9 - 13 years
11 mg (16.4 IU)
> 14 years
15 mg (22.4 IU)
19 mg (28.4 IU)
Key Point: There are several different forms of vitamin E and alpha tocopherol is the most important. The RDA for adults is 15 mg per day.
What Is the Role of Vitamin E In the Body?
As previously mentioned, vitamin E works as an antioxidant.
For this reason, we can find vitamin E tocopherols as a food additive in various foods to preserve their freshness and reduce oxidation of fats.
For example, you can commonly see the following food additives on labels; E306 (tocopherols mix), E307 (alpha-Tocopherol), E308 (gamma-Tocopherol), E309 (delta-Tocopherol).
Similarly, vitamin E plays the same role within the human body; it protects our cells, tissues, and organs from oxidative damage (5).
Through its role in fighting free radical damage and boosting the immune system, vitamin E helps keep our body functioning optimally.
Vitamin E Health Benefits
Now that we know the role of vitamin E, we will look at the specific benefits it can have in the human body.
1) Strengthens the Immune System and Fights Disease
Vitamin E plays an essential role in immune response and helps to boost our entire immune system.
To understand the vitamin's importance, markers of immune health all decline in the presence of vitamin E deficiency.
On this note, human studies in this area demonstrate that low vitamin E levels impair cell immune functions (6).
Furthermore, a diet high in vitamin E helps to improve declining immunity levels that come as we age (7).
Since higher vitamin E levels increase immunity, there is a theory that the vitamin may help as a cancer prevention agent too.
Although this requires further human research, animal studies appear to show positive results.
Specifically, preclinical animal studies show that tocopherols can prevent the progression of several different cancers (8).
Key Point: Vitamin E boosts the immune system and helps to prevent illness.
2) May Help Protect Cardiovascular Health
Studies show an inconsistent link between vitamin E levels and cardiovascular health.
Firstly, there are the benefits that come from vitamin E functioning as an antioxidant as well as improving immune response.
A review of randomized clinical trials shows vitamin E to be cardioprotective in patients experiencing a significant amount of oxidative stress.
However, the potential benefits are not apparent in healthy individuals. This fact suggests optimal vitamin E levels may be more important for people suffering from more significant oxidative stress (9).
Secondly, evidence from in vitro (cell culture) studies demonstrates that vitamin E can inhibit the oxidation of LDL cholesterol. Oxidized LDL is believed to play a significant role in the development of atherosclerosis (hardening of the arteries) (10).
However, there is no way to prove this happens in the same way within the human body and this needs more research.
The type of vitamin E may be an important consideration too.
In one study, researchers followed 5,133 Finnish adults for a total of 14 years. Among this group, those who had the highest intake of vitamin E from food had significantly less mortality from cardiovascular disease (11).
In contrast, randomized controlled trials do not seem to find cardiovascular benefit from vitamin E supplementation (12).
Key Point: Higher vitamin E intake may reduce the risk of cardiovascular mortality. However, there is little evidence for supplementation.
3) May Help Prevent Cognitive Decline
Cognitive decline due to conditions like Alzheimer's and dementia is a rising problem in the modern world.
Sadly, 1 in 3 senior citizens now dies from Alzheimer's or a different form of dementia (13).
On the positive side, several studies suggest that higher vitamin E levels could help protect against cognitive decline.
Here is a summary of some research in this area;
Can Supplementation Prevent Dementia?
Given higher plasma levels of vitamin E can help lower the risk of dementia, can supplementation help prevent the progression of mild cognitive impairment?
Unfortunately, the data is unconvincing.
A Cochrane review of clinical trials found no evidence that vitamin E supplementation could prevent mild cognitive impairment progression to dementia (17).
Key Point: Higher plasma levels of vitamin E seem to provide benefits in dementia. However, dietary supplementation does not stop progression from cognitive impairment to dementia.
4. Has Protective Effects For Smokers
It is no secret that smoking is one of the worst things we can do for our health, and the best way to protect against smoking-related disease is to quit.
However, for those who choose to smoke, vitamin E levels are an essential consideration.
Since cigarette smoke contains numerous pro-oxidants and free radicals, it generates large amounts of oxidative stress. Optimal vitamin E levels may help to prevent some of the damage.
On the negative side, smoking depletes vitamin E levels, which increases dietary requirements (18).
Key Point: Vitamin E from natural food sources appears to help reduce the risk of lung cancer in smokers.
5. Regulates Gene Expression
Vitamin E may regulate gene expression.
Gene expression refers to the process by which information from DNA and genes is synthesized into a biological product, such as protein. It is also crucial for procedures such as DNA repair.
Unfortunately, gene expression often declines as we age (21).
Key Point: Vitamin E appears to play an important role in gene expression.
6. Exhibits Positive Effects on Osteoarthritis
Osteoarthritis is a chronic joint disease that can make movement difficult and it often leads to chronic pain.
This common condition has a severe impact on the elderly, and it is the most common cause of disability in older age groups (25).
In recent years, numerous trials have examined the potential health benefits of vitamin E on osteoarthritis.
Key Point: Higher vitamin E levels may help reduce the negative effects of osteoarthritis.
7) Vitamin E Is Important For Healthy Aging
Aging is a complicated biological process that affects everyone in a similar, yet very different way.
Factors such as oxidative stress and chronic inflammation can turn various "bad" genes on, damage our DNA and cause all kinds of degenerative, chronic disease.
However, vitamin E has the role of scavenging free radicals and protecting cells from oxidative stress.
Key Point: Maintaining adequate vitamin E levels may help to prevent the adverse effects of aging.
Best Food Sources of Vitamin E
To maintain a sufficient dietary intake of vitamin E, it is important to know the best food sources of the vitamin.
In the list below, you can find twelve healthy vitamin E-rich foods.
On the positive side, most of them taste good too.
1) Almonds (37% RDA per ounce)
Almonds are one of the best dietary sources of vitamin E, and just one ounce (28 grams) provides 37% of the recommended daily allowance (32).
Also, almonds have an impressive overall nutrition profile, and they are rich sources of several major vitamins and minerals.
Try a handful of salted almonds as a snack; they taste great on their own, and you can also coat them in dark chocolate for an easy-to-make treat.
2) Trout (17% RDA per fillet)
Trout is a delicious (and cheaper) alternative to salmon and matches up well nutritionally.
Per fillet of trout, we can obtain 17% of the RDA for vitamin E (33).
Trout works well in a wide range of recipes, and it combines well with creamy fish sauces.
If you want to try out a new recipe, here is a delicious trout in lemon parmesan sauce recipe.
3) Avocado (21% RDA per fruit)
Avocados are delicious and very nutrient-dense.
This fatty fruit is also a good source of vitamin E, with one California avocado providing around 21% of the RDA (34).
As well as their vitamin content, avocados are a rich source of healthy fat and several essential minerals, including potassium and magnesium.
4) Spinach (10% RDA per 100 g)
Spinach is an extremely nutritious leafy green vegetable.
Except for vitamin D, spinach provides just about every single vitamin and mineral.
Regarding its vitamin E content, spinach supplies about 10% of the RDA per 100 grams (35).
While spinach is not the highest source of this fat-soluble vitamin on a per-gram basis, it is the most significant source per calorie.
Although spinach can be a little bitter on its own, it tastes delicious sauteed in butter with a bit of salt.
5) Hazelnuts (21% RDA per ounce)
Hazelnuts do not provide as much vitamin E as almonds, but they are still a decent source of the vitamin.
Per ounce, hazelnuts supply 21% of the RDA (36).
Similar to almonds, they are a nice-tasting and nutritious nut that provide a wealth of essential nutrients.
6) Sunflower Seeds (47% RDA per ounce)
Sunflower seeds are the most concentrated food source of vitamin E and provide a substantial 47% of the RDA per ounce (37).
On the negative side, they are not the best-tasting food in the world.
However, a handful of sunflower seeds from time to time can fit into a healthy diet.
7) Extra Virgin Olive Oil (10% RDA per tbsp)
Olive oil is a rich source of vitamin E, and it provides 10% of the RDA per tablespoon (38).
Extra virgin olive oil is one of (if not THE) healthiest fats in the world whether used as a salad dressing or cooking oil.
In fact, a recent study demonstrated that genuine extra virgin olive oil performs better at high-heat than any other cooking oil (39).
8) Shrimp (9% RDA per 100 grams)
Shrimp are a nutrient-dense small crustacean species.
Per 100 grams of shrimp, it supplies 9% of the RDA for vitamin E (40).
However, there are many other reasons to include this nutritious shellfish in the diet.
For example, shrimp provides high-quality protein, a range of vitamins and minerals, and a decent source of omega-3 fatty acids.
9) Swiss Chard (9% RDA per 100 grams)
Alongside spinach, swiss chard is one of the most nutrient-dense vegetable options.
Per 100 grams (and per 19 calories,) swiss chard contains a reasonable 9% of vitamin E's RDA (41).
Similar to spinach, swiss chard works best when sauteed; this gives it the best taste and increases the absorption of its fat-soluble vitamins.
10) Atlantic Salmon (35% RDA per 1/2 fillet)
Salmon is one of the healthiest choices of fish on the planet, and it has an impressive vitamin E content too.
Half a fillet commonly provides 35% of the fat-soluble vitamin's RDA (42).
In addition to the impressive range of nutrients salmon provides, it is also one of the most significant dietary sources of omega-3.
It tastes delicious too.
11) Abalone (20% RDA per 100 grams)
Abalone is a nutrient-dense shellfish species that provides large amounts of protein and an impressive range of nutrients.
This healthy mollusk offers a decent serving of vitamin E too, and it provides 20% of the recommended allowance per 100 grams (43).
12) Pine Nuts (13% RDA per ounce)
Pine nuts are one of the least known nut varieties, but they are relatively nutrient-dense.
In addition to their substantial amount of the mineral manganese, pine nuts provide 13% of the RDA for vitamin E per ounce (44).
Pine nuts work well in baking, sprinkled on top of salads, roasted, or just eaten raw.
Key Point: There are numerous dietary sources of vitamin E; nuts and seeds, marine foods and plant fats are notably high in the nutrient.
Vitamin E Deficiency Symptoms
As with any essential nutrient, there will be a variety of deficiency symptoms that show up if there is a prolonged inadequate intake.
Although many people fall short of the RDA for vitamin E, most people still consume enough to avoid these deficiency symptoms.
However, one potential issue is the groups of people who suffer from fat-malabsorption.
Since vitamin E is a fat-soluble vitamin, the risk for deficiency is much more significant for these individuals.
Anyone with any concerns regarding this issue should discuss with a doctor/medical professional.
Key Point: Aside from people with fat malabsorption disorders, problems from vitamin E deficiency are rare.
Dietary Supplements and Health Risks
Care should be taken with vitamin E supplements.
As mentioned throughout this article, various studies demonstrate benefits from food sources of vitamin E.
However, many studies also show potential harm from dietary supplementation with vitamin E.
1) Vitamin E Supplements May Increase the Risk of Cancer
Significantly, studies have found an association between supplementation and lung and prostate cancers;
The question here is why supplementation would have such an effect when dietary sources of vitamin E do not appear to?
At present, there is no conclusive answer to that question.
However, researchers theorize that large, pure doses of antioxidants may kill too many free radicals.
For example, vitamin E supplements contain much higher doses than the RDA (49).
While excessive amounts of free radicals can cause oxidative damage, they also do have some beneficial effects. For one thing, they can kill cancer cells.
In other words; not only might high-dose vitamin E protect our healthy cells from damage, but also cancer cells.
A review of randomized clinical trials backs this point up too; cancer patients using antioxidant supplements have worse outcomes (50).
Key Point: Vitamin E supplementation appears to increase the risk of certain cancers.
2) Vitamin E Supplements Can Interfere With Medications
Supplementing with vitamin E while taking medication can potentially inhibit the effect of various medications.
For instance, large vitamin E doses can reduce blood clotting and increase the risk of bleeding.
Taking the vitamin alongside anticoagulant (blood thinning) medications like warfarin could, therefore, increase the risk of bleeding (51).
There are various other potential interactions between drugs and vitamin E, and anyone using medication should always discuss with their doctor.
Key Point: Large doses of vitamin E can cause bleeding, particularly in combination with anticoagulant medicines.
Best Source: Diet vs Dietary Supplements
Overall, the evidence is clear that natural food sources of vitamin E are more ideal than supplementation.
Studies are supportive of a protective effect from higher vitamin E intake from food sources.
On the other hand, high-dose supplementation appears to increase the risk of various health problems.
All in all, getting vitamin E from food seems to be a lot safer, and it saves money too.
Lastly, eating delicious food is much more enjoyable than popping a pill.