What is E308?
Complete guide to understanding E308 (Gamma-Tocopherol) — a lesser-known vitamin E form with unique antioxidant properties
The Quick Answer
E308 (Gamma-Tocopherol) is a form of vitamin E — an essential nutrient and powerful antioxidant used to prevent fats and oils in foods from becoming rancid.
E308 is less commonly used than E307 (alpha-tocopherol), but it has unique antioxidant properties, particularly effectiveness against certain inflammatory free radicals.
It’s one of the safest food additives, approved globally, with no documented safety concerns at food use levels — though regulators acknowledge needing more comprehensive safety data compared to the more widely-used E307.
📌 Quick Facts
- Chemical Name: Gamma-Tocopherol (γ-tocopherol); a form of vitamin E
- Type: Natural antioxidant and essential nutrient; one of four tocopherols comprising vitamin E
- Found in: Some oils and fats, snacks, baked goods, prepared foods, margarine, salad dressings (less common than E307)
- Safety Status: Safe and approved; “not of safety concern” at food use levels (EFSA 2015)
- Approved by: EFSA, FDA, JECFA, Australia, New Zealand, Canada, all major jurisdictions
- Tolerable Upper Intake Level: 300 mg/day for ALL vitamin E forms combined (from all sources)
- Regulatory note: EFSA noted dataset “limited” compared to E307; called for more data (2018)
- Vitamin E activity: ~30% of alpha-tocopherol (E307); lower potency but unique properties
- Main benefit: Prevents food rancidity + provides vitamin E with anti-inflammatory potential
What Exactly Is It?
E308 is gamma-tocopherol, one of eight forms of vitamin E — either extracted from plant oils or synthetically produced. Either way, the antioxidant activity is identical.
Chemical formula: C₂₉H₅₀O₂ (identical to alpha-tocopherol E307, but with different 3D molecular arrangement)
Key properties:
– Antioxidant in fats and oils
– One of the essential vitamin E forms
– Fat-soluble; integrates into cell membranes
– Neutralizes certain types of free radicals (especially inflammatory radicals)
– Naturally present in vegetable oils, nuts, seeds
– Can be extracted from plants (wheat germ, rice, corn, soy) OR synthesized chemically
– Lower potency than alpha-tocopherol (E307) but unique antioxidant profile
– Less preferentially absorbed by liver than alpha-tocopherol
Important distinction within vitamin E:
Vitamin E is NOT a single compound. It’s a family of eight related compounds (four tocopherols, four tocotrienols). Of these eight:
– Alpha-tocopherol (E307): Most biologically active; strongest vitamin E activity
– Gamma-tocopherol (E308): ~30% potency of alpha; unique anti-inflammatory properties
– Delta-tocopherol (E309): Very low vitamin E activity; ~3% of alpha
– Tocopherol-rich extract (E306): Natural mixture of multiple forms
Where You’ll Find It
E308 is found in various foods, though less commonly than E307:
| Category | Specific Examples | Function |
|---|---|---|
| Oils & Fats | Margarine, salad dressings, oils | Prevents oxidation and rancidity |
| Snacks & Pastries | Crackers, baked goods, pastries | In fat-containing products |
| Prepared Foods | Sauces, soups, sandwich cheeses | Antioxidant preservation |
| Dairy Products | Cheese, yogurt, fermented dairy | Preservation and nutrition |
| Meat Products | Some processed meats | Fat protection |
| Cocoa Products | Some chocolate and cocoa products | Fat preservation |
| Animal Feed | Approved for all animal species | Preservation and nutrition |
Permitted levels: Much lower concentration levels and fewer uses reported than E307; regulated as part of vitamin E limits.
Why Use E308? Unique Antioxidant Profile
E308 isn’t just a cheaper or weaker version of E307—it has unique properties:
1. Different Free Radical Neutralization:
– Gamma-tocopherol particularly effective against lipid peroxyl radicals
– Superior antioxidant capacity against certain inflammatory free radicals
– May be more effective than alpha-tocopherol in specific oxidative environments
2. Anti-inflammatory Potential:
– Research suggests gamma-tocopherol may have stronger anti-inflammatory effects
– Particularly interesting for inflammatory diseases and chronic conditions
– Less studied than alpha-tocopherol but preliminary evidence encouraging
3. Synergistic Use:
– Often combined with alpha-tocopherol (E307) for broader antioxidant coverage
– Different forms protect against different types of oxidative stress
– Together: broader spectrum preservation than either alone
Why E308 instead of only E307?
– Specialized antioxidant function
– Research into unique health benefits
– Broader vitamin E profile in food
– Cost considerations (less expensive than E307)
– Natural variant found in plant sources
Is It Safe? Definitely Yes
The Official Position
E308 is safe and approved globally. The only caveat is that regulatory data is less extensive than for E307.
| Authority | Position | Safety Finding | Status |
|---|---|---|---|
| EFSA (2015) | Approved; part of vitamin E group | “Not of safety concern at food use levels” | Stable approval |
| EFSA (2018 call) | Requested more data | “Dataset on γ-tocopherol was limited” | Not a safety concern; just need more data |
| JECFA (WHO) | Approved | ADI 0.15-2 mg/kg (tocopherols generally) | Ongoing approval |
| FDA (US) | GRAS (Generally Recognized As Safe) | No safety concerns | Approved |
| All major jurisdictions | Approved globally | Safe; limited data doesn’t mean unsafe | Global approval |
Important Clarification: “Limited Dataset” ≠ Unsafe
EFSA’s statement that E308 has a “limited dataset” is important to understand correctly:
– NOT unsafe: All available data show NO adverse effects
– Limited comparison: Means less comprehensive data than for E307
– Research volume: Fewer studies than the widely-used alpha-tocopherol
– Usage levels: Much lower concentration levels in foods
– Safety conclusion: “Not of safety concern at the levels used in food”
– EFSA request: Called for more comprehensive data to fill gaps
– Approval status: Maintained; approval conditional on future data submission
Safety Assessment
| Safety Criterion | Finding | Conclusion |
|---|---|---|
| Acute Toxicity | Very low at food use levels | Safe to consume |
| Chronic Toxicity | No observed adverse effects; NOAEL 125 mg/kg bw/day (animal studies) | Safe for long-term exposure |
| Genotoxicity | No concern; not genotoxic | Does not damage DNA |
| Carcinogenicity | No concern; not carcinogenic | Does not cause cancer |
| Vitamin E Activity | ~30% of alpha-tocopherol; but unique properties | Lower potency but different antioxidant profile |
| Overall Assessment | EFSA: “Not of safety concern”; Approval maintained | Among safest additives available |
Tolerable Upper Intake Level (UL)
Tolerable Upper Intake Level (UL): 300 mg/day for ALL vitamin E forms combined (from all sources)
This is a combined limit for all eight forms of vitamin E (E306, E307, E308, E309, plus their tocotrienol equivalents, plus natural dietary intake).
For perspective:
– Typical diet: 5-15 mg/day vitamin E naturally
– Food additives: Usually 10-100 mg per serving
– Combined daily exposure: Well below 300 mg/day UL
– E308 alone: Much lower than E307 at equivalent product use
E308 vs. E307: Understanding the Difference
| Property | E307 (Alpha-Tocopherol) | E308 (Gamma-Tocopherol) |
|---|---|---|
| Vitamin E Activity | 100% (reference standard) | ~30% of alpha |
| Regulatory History | Extensive; well-studied | Limited; EFSA called for more data |
| Common Use | Very common | Less common; specialized use |
| Antioxidant Potency | High; versatile | High; particularly good for inflammatory radicals |
| Anti-inflammatory Effects | Some | Potentially stronger |
| Body Absorption | Preferentially absorbed; liver selectively retains | Lower preferential absorption; less selective retention |
| Unique Properties | High overall vitamin E activity | Unique inflammatory response pattern |
| Safety | No concern at food levels | No concern at food levels |
Key insight: E307 is more commonly used because it has higher vitamin E activity and more extensive regulatory history. E308 is used where its unique anti-inflammatory properties are desired. Both are equally safe.
Health Benefits (Beyond Food Preservation)
E308, like all vitamin E forms, provides health benefits:
– Antioxidant protection: Neutralizes free radicals damaging cells
– Anti-inflammatory potential: May be particularly effective against inflammatory radicals
– Immune function: Supports healthy immune response
– Cardiovascular health: Protects blood vessels and cardiovascular function
– Neurological protection: May help prevent neurodegenerative diseases
– Skin health: Protects against UV damage and aging
– Essential nutrient: Deficiency causes serious neurological disorders
Special interest in E308: Gamma-tocopherol’s particular effectiveness against inflammatory free radicals makes it of special research interest for chronic inflammatory diseases.
The Bottom Line
E308 (Gamma-Tocopherol) is a safe and approved vitamin E form with unique antioxidant properties.
What you should know:
- It’s safe: EFSA found it “not of safety concern” at food use levels
- Limited data doesn’t mean unsafe: Means less comprehensive regulatory history than E307; all available data show safety
- It’s nutritious: Provides essential vitamin E alongside preservative function
- It’s unique: Different antioxidant profile than alpha-tocopherol (E307)
- It’s globally approved: No regulatory controversy or restrictions
- It’s less common: Much lower use levels than E307; specialized applications
- It’s a form of vitamin E: Essential for human health; deficiency causes disease
- Safe for children: Approved for use in children’s foods