Gamma-tocopherol

also: Synthetic gamma-tocopherol · Vitamin E (gamma form)

A synthetic form of vitamin E added to oils, fats and processed foods to stop them going rancid by neutralising harmful free radicals.

Get NutraSafe on the App Store →

Scan a barcode to check a food for gamma-tocopherol. NutraSafe Pro · £6.99/month · iPhone and Android

E308Antioxidant · Synthetic

Gamma-tocopherol

Gamma-tocopherol is one of four tocopherol isomers (alpha, beta, gamma, delta) that together make up vitamin E.

VeganVegetarianHalalKosher

What gamma-tocopherol is, what it does and where you will see it

What is it?

Gamma-tocopherol is one of four tocopherol isomers (alpha, beta, gamma, delta) that together make up vitamin E. E308 is specifically the synthetic form, dl-gamma-tocopherol, produced from vegetable-oil distillation fractions or by chemical synthesis. Gamma-tocopherol is the predominant tocopherol in many vegetable oils such as soybean and corn oil, and occurs naturally in a wide range of plant foods. As a food additive it is chemically identical to the naturally occurring compound but may contain a mixture of stereoisomers (the dl- form) rather than the single d- form found in nature.

What does it do?

Gamma-tocopherol is a fat-soluble antioxidant. It works by donating a hydrogen atom to lipid peroxy radicals, breaking the chain reaction of lipid oxidation that turns fats rancid and produces off-flavours. Compared with alpha-tocopherol (E307), gamma-tocopherol is less potent as a vitamin E nutrient but is notably effective at trapping reactive nitrogen species such as peroxynitrite, giving it a slightly different antioxidant profile. In food, it protects unsaturated fatty acids in oils and fat-rich products from oxidative degradation during storage and processing.

Where you will see it

Most commonly added to vegetable oils, margarines, spreads, cooking fats, salad dressings, infant formula, dry breakfast cereals, snack foods, baked goods and ready meals containing added fat. It may also appear in nutritional supplements and fortified foods. On a UK ingredient label it appears as 'gamma-tocopherol', 'E308', or 'antioxidant (E308)'.

What the science says

EFSA re-evaluation: no concern at food-use levels

In 2015, the European Food Safety Authority's Panel on Food Additives and Nutrient Sources completed a full re-evaluation of synthetic gamma-tocopherol (E308) alongside the other tocopherol additives (E306-E309). The Panel concluded that tocopherols at the levels used in food are not of safety concern. No numerical acceptable daily intake was considered necessary because the compounds are normal dietary constituents and vitamin E metabolites.

EFSA concluded synthetic gamma-tocopherol (E308) is not of safety concern at levels used as a food additive; no numerical ADI was set for the tocopherol group.

2015Regulatory reviewEFSA Panel on Food Additives and Nutrient Sources (ANS), EFSA Journal 2015;13(6):4247

Gamma-tocopherol versus alpha-tocopherol: different roles

Gamma-tocopherol differs from alpha-tocopherol in its side chain, which gives it weaker classical vitamin E activity but stronger ability to neutralise reactive nitrogen species. Research has investigated whether gamma-tocopherol has distinct anti-inflammatory properties in the body, separate from its antioxidant function in food. This research is preliminary and does not alter the food-additive assessment.

Gamma-tocopherol can trap and detoxify reactive nitrogen species such as peroxynitrite more efficiently than alpha-tocopherol, a property linked to potential anti-inflammatory effects in cell and animal studies.

2001Lab + animalJiang Q et al., Proceedings of the National Academy of Sciences

Alpha-tocopherol supplementation can displace gamma-tocopherol from plasma, reducing circulating gamma-tocopherol concentrations; the clinical significance of this displacement at food-additive exposure levels is not established.

1994ObservationalHandelman GJ et al., American Journal of Clinical Nutrition

Synthetic (dl-) versus natural (d-) form

The E308 additive is the synthetic racemic mixture (dl-gamma-tocopherol), meaning it contains stereoisomers not found in nature alongside the natural form. Alpha-tocopherol research has established that synthetic dl-alpha-tocopherol has lower biological vitamin E activity than natural d-alpha-tocopherol. For gamma-tocopherol the practical difference in antioxidant food-protection function is not considered meaningful at additive use levels.

Synthetic dl-alpha-tocopherol has approximately 74% of the biological vitamin E activity of natural d-alpha-tocopherol; analogous stereoisomer differences exist for other tocopherol forms but are not considered safety-relevant at food additive levels.

2000RegulatoryInstitute of Medicine, Dietary Reference Intakes for Vitamin C, Vitamin E, Selenium, and Carotenoids

Where it stands with the regulators

Approved for use in the UK and EU

Legal basis: UK FSA approved-additives list and assimilated EU Regulation (EC) No. 1333/2008, Annex II. UK authorisation confirmed as of 31 December 2020, applying in England, Scotland and Wales.
Permitted foods: Vegetable oils and fats; Margarines and fat spreads; Infant formula and follow-on formula; Processed cereal-based baby foods; Breakfast cereals; Baked goods and pastries; Snack foods; Dried soups and seasonings; Ready meals containing added fat; Nutritional supplements (in combination with other tocopherols)
Maximum levels: Varies by food category under Annex II; quantum satis (as much as needed to achieve the technological function) applies in many oil and fat categories
Acceptable daily intake (ADI): No numerical ADI set (EFSA 2015: tocopherols not of safety concern at food-use levels; group ADI 'not specified')
History: Tocopherols as a group (E306-E309) have been permitted food additives in EU and UK for decades. EFSA completed a systematic re-evaluation in 2015, maintaining the approval without restriction. Following UK departure from the EU, the authorisation was carried over into UK law as of 31 December 2020. No bans, restrictions, or warning-label requirements have ever applied to E308.

Who should be careful

No specific population group is required to avoid E308 at food-additive levels. People taking high-dose alpha-tocopherol supplements should be aware that high supplemental alpha-tocopherol can reduce blood gamma-tocopherol levels, but this is a supplement interaction, not a food-label concern. Look for 'E308' or 'gamma-tocopherol' in the ingredients list.

The honest read

Gamma-tocopherol is a normal component of many vegetable oils and plant foods. As a food additive (E308) it is the synthetic version of that same compound. The EFSA re-evaluation in 2015 found no grounds for concern at the quantities used in food. Some researchers are interested in whether gamma-tocopherol's ability to neutralise nitrogen-based free radicals gives it health benefits beyond basic antioxidant function, but that research is preliminary and separate from the question of whether the additive is a problem. There is no active regulatory concern, no campaigning body has flagged it, and it carries no warning requirement anywhere in the UK or EU.

Common questions about gamma-tocopherol

Is E308 banned in the UK?

No. E308 gamma-tocopherol is approved for use in the UK under the assimilated EU Regulation 1333/2008, confirmed as of 31 December 2020 and applying in England, Scotland and Wales.

Is E308 the same as vitamin E?

Gamma-tocopherol is one of the eight compounds that collectively have vitamin E activity, but it is less potent than alpha-tocopherol (E307), which is the main form measured in vitamin E nutrition. As a food additive, E308 is present to protect the food from going rancid, not to provide a nutritional dose of vitamin E.

What foods contain E308?

E308 is most commonly added to vegetable oils, margarines, spreads, infant formula, breakfast cereals, baked goods, snacks and ready meals containing added fat. On the label it appears as 'gamma-tocopherol', 'E308', or 'antioxidant (E308)'.

Is E308 vegan?

Yes. Gamma-tocopherol (E308) is derived from vegetable-oil sources or produced synthetically, and contains no animal-derived ingredients. It is suitable for vegans and vegetarians.