What are the side effects of E306 food additive?

January 10, 2026 •

3 min read

The European Food Safety Authority (EFSA) and the FDA generally consider the E306 food additive, a tocopherol-rich extract, safe in the small concentrations typically used in food products. However, consumers should understand that potential side effects are associated with excessive consumption from supplements, and certain individuals may experience sensitivities.

Quick Summary

E306, a vitamin E-based antioxidant, is safe at normal food levels but can cause gastrointestinal issues or other effects in high doses. Allergic reactions are also a potential risk for those sensitive to its source ingredients.

Key Points

Dose Matters: Side effects of tocopherols (E306) are primarily linked to high-dose vitamin E supplements, not the small amounts used in food additives.
Minimal Food Risk: Regulatory bodies consider E306 safe in food products, with concentrations too low to cause typical vitamin E toxicity.
High-Dose Symptoms: Excessive supplemental vitamin E can cause side effects like nausea, diarrhea, headaches, and fatigue.
Increased Bleeding Risk: Very high doses of vitamin E can increase the risk of bleeding, a significant concern for those on anticoagulant medication.
Allergy Caution: E306 is often derived from soy or corn, so individuals with allergies to these ingredients should be vigilant for potential reactions.
Preservative Function: The main purpose of E306 in food is to act as an antioxidant, preventing fats from becoming rancid and extending product shelf life.

E306: A Tocopherol-Rich Antioxidant

E306 is a food additive also known as a tocopherol-rich extract, which functions as a fat-soluble antioxidant. It is essentially a concentrated form of vitamin E, naturally extracted from vegetable oils such as soybean, corn, and sunflower oil. The primary purpose of E306 in food manufacturing is to prevent fats and oils from oxidizing, which causes them to go rancid and spoil. By protecting these ingredients, E306 extends the shelf life of various products without affecting their taste, color, or smell when used at approved levels. Its use is widespread in fatty products like margarine, vegetable oils, breakfast cereals, snacks, and sauces.

Side Effects from High-Dose Supplementation

Most reported adverse effects linked to tocopherols are associated with high-dose vitamin E supplements, not the minimal amounts added to food. Regulatory bodies worldwide, including the FDA and EFSA, have concluded that E306 is not a safety concern at the levels approved for use in food. Side effects from very high supplemental intake include:

Gastrointestinal issues: Nausea, diarrhea, and stomach cramps.
Neurological symptoms: Headaches, dizziness, and blurred vision.
Fatigue and weakness: A general feeling of tiredness and muscle weakness.

The Most Serious Side Effect: Increased Bleeding Risk

The most significant and dangerous side effect of excessive vitamin E is an increased risk of bleeding. This risk is especially elevated in adults also taking blood-thinning medications, such as warfarin. High doses of vitamin E can affect blood coagulation, and in very serious cases, this can lead to a brain hemorrhage. It is critical to differentiate this risk, associated with supplements, from the safety of E306 in food products, which is used in very small quantities.

Allergy Risks Associated with E306

For the vast majority of people, E306 does not pose an allergy risk. However, since the additive is extracted from common allergens like soy and corn, individuals with known allergies to these substances should be cautious. Allergic reactions are a rare but possible side effect and can manifest as:

Skin rashes and itching.
Hives.
Severe allergic reactions, though rare, can also occur. If you have a severe allergy to soy or corn, always check the label of products that might contain E306 and, when in doubt, consult a healthcare provider.

E306 Food Additive vs. Vitamin E Supplements: A Comparison

To understand the safety profile, it is crucial to recognize the significant difference in concentration and purpose between E306 in foods and high-dose vitamin E supplements. The following table outlines the key differences:


Feature	E306 in Food	High-Dose Vitamin E Supplements
Concentration	Very low levels, just enough to preserve the product.	High, concentrated doses, often exceeding daily needs.
Purpose	To act as an antioxidant and preservative to extend shelf life.	To provide a therapeutic dose of vitamin E for health purposes.
Health Risks	Generally considered safe, with minimal risk of adverse effects.	Increased risk of side effects, including bleeding, with overuse.
Regulation	Subject to strict usage level regulations by bodies like EFSA.	Often available over-the-counter with less stringent regulation on dosage.
Source	Commonly derived from natural vegetable oils like soy or corn.	Can be derived from natural sources (d-α-tocopherol) or produced synthetically (dl-α-tocopherol).

Who Should Be Cautious with Vitamin E?

While E306 in food is generally safe, certain groups should be mindful of their total vitamin E intake, especially from supplemental sources. It is advisable to consult a healthcare provider before taking any vitamin E supplements.

Key populations who should exercise caution include:

Individuals taking blood-thinning medication (anticoagulants).
Pregnant and breastfeeding women.
Individuals with pre-existing medical conditions, including bleeding disorders, cardiovascular problems, or certain intestinal diseases.

Conclusion: E306 is Safe, but Overconsumption is Not

In summary, the E306 food additive, a form of vitamin E used as an antioxidant, is considered safe for consumption at the low levels present in food products. The adverse effects associated with tocopherols, such as gastrointestinal upset and an increased risk of bleeding, occur primarily from the overconsumption of high-dose dietary supplements. The main risk related to food containing E306 is for individuals with allergies to its source ingredients, such as soy or corn. Consumers should practice moderation, maintain a balanced diet, and consult a healthcare professional regarding supplementation to ensure optimal health and safety. For more information on vitamin E and health, consult reputable organizations like the World Health Organization (WHO).

Frequently Asked Questions

E306 is a food additive that refers to a tocopherol-rich extract, which is a form of vitamin E derived from vegetable oils like soybean and corn.

No, E306 is generally considered safe when used at standard levels in food products. Adverse effects are extremely unlikely from the low concentrations used for preservation.

Gastrointestinal issues like nausea and diarrhea can occur from consuming high doses of vitamin E supplements, but not typically from the small amount of E306 found in food additives.

No, they are not the same. E306 in food is a minimal, regulated amount for preservation, while vitamin E supplements contain much higher, concentrated doses for therapeutic purposes.

Yes, it is possible to have an allergic reaction if E306 is derived from an ingredient you are allergic to, such as soy or corn. Always check the product's origin if you have severe allergies.

The risk of increased bleeding is associated with high-dose vitamin E supplements and does not apply to the minimal, safe amounts of E306 used in food.

Individuals with bleeding disorders, those on anticoagulant medications, pregnant or breastfeeding women, and those with certain medical conditions should consult a healthcare provider about their vitamin E intake, especially from supplements.