What is E309?
Complete guide to understanding E309 (Delta-Tocopherol) — the rarest and weakest vitamin E form, almost never used as a food additive
The Quick Answer
E309 (Delta-Tocopherol) is a form of vitamin E — an essential nutrient and antioxidant that’s theoretically used to prevent fats and oils from becoming rancid.
However, E309 is almost never actually used as a food additive in practice due to its extremely low vitamin E potency (~3% of alpha-tocopherol E307) and a strong flavor that makes it unsuitable for food applications.
It’s approved globally and safe, but so rarely used that most consumers will never encounter it listed on a food label. When tocopherols are used, E307 or the mixed extract E306 are the standard choices.
📌 Quick Facts
- Chemical Name: Delta-Tocopherol (δ-tocopherol); a form of vitamin E
- Type: Natural antioxidant and essential nutrient; one of four tocopherols comprising vitamin E
- Found in: Almost nowhere in food (virtually never used as additive)
- 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
- Food-Info ADI guidance: Up to 2 mg/kg body weight/day (most restrictive of tocopherols)
- Vitamin E activity: ~3% of alpha-tocopherol (E307) — EXTREMELY LOW
- Real-world use: Virtually non-existent; never encountered in typical food shopping
What Exactly Is It?
E309 is delta-tocopherol, the least potent of the four tocopherol forms of vitamin E — either extracted from plant oils or synthetically produced.
Chemical formula: C₂₉H₅₀O₂ (identical to alpha-tocopherol E307, but with different 3D molecular arrangement)
Key properties:
– One of the eight forms of vitamin E
– Antioxidant in theory; rarely used in practice
– Fat-soluble; integrates into cell membranes
– Naturally present in vegetable oils (soybean, corn)
– Can be extracted from plants OR synthesized chemically
– LOWEST potency of the four tocopherols (~3% vitamin E activity)
– STRONG flavor — major limitation for food use
– Almost never encountered as standalone additive
Important distinction within vitamin E:
Vitamin E is a family of eight compounds (four tocopherols, four tocotrienols), ranked by potency:
– Alpha-tocopherol (E307): 100% activity; most common
– Beta-tocopherol: ~40% activity
– Gamma-tocopherol (E308): ~30% activity
– Delta-tocopherol (E309): ~3% activity; LOWEST; almost never used
Where You’ll Find It (Spoiler: Nowhere)
E309 is virtually never used as a food additive.
| Category | Use in Food | Why Not E309? |
|---|---|---|
| Cooking Oils & Fats | E307 or E306 used instead | E309 too weak; strong flavor imparts off-taste |
| Margarine | E307 or E306 used instead | E309 would require high concentration; prohibitive flavor |
| Processed Foods | E307 or E306 used instead | E309 ineffective; would need massive quantities |
| Snacks & Baked Goods | E307 or E306 used instead | E309 not practical; inferior performance |
| Any food product | E309 essentially never encountered | Multiple better alternatives available |
Reality check: If you’re reading food labels looking for antioxidant vitamin E additives, you might see E307 (alpha-tocopherol) or E306 (tocopherol-rich extract). You will virtually never see E309 listed.
Why E309 Is Almost Never Used
E309 suffers from multiple practical limitations that make it unsuitable for food:
1. Extremely Low Potency:
– Only ~3% of alpha-tocopherol (E307) vitamin E activity
– Would require 30-40x higher concentration than E307
– Economically infeasible
– Makes E307 vastly superior choice
2. Strong, Unpleasant Flavor:
– Imparts strong taste at food-relevant concentrations
– Makes products unpalatable
– Major barrier to food use
– Both E307 and E308 have minimal flavor impact
3. Inferior Performance:
– Lower antioxidant effectiveness
– Cannot match E307 or E306 results
– Requires higher concentrations for same effect
– Still doesn’t work as well even at higher concentrations
4. Cost-Ineffective:
– More expensive per unit of vitamin E activity
– E307 or E306 mixtures are more economical
– No cost advantage
– Multiple disadvantages combined with no benefits
5. Better Alternatives Exist:
– E307 (alpha-tocopherol): More potent; minimal flavor
– E306 (tocopherol-rich extract): Mixed natural forms; already widely used
– E308 (gamma-tocopherol): More potent; useful for specialized applications
– All superior to E309 in every practical respect
Result: E309 is theoretically approved but practically never used. Food manufacturers have no reason to choose E309 over E307 or E306.
Is It Safe? Definitely Yes (But Not Relevant)
The Official Position
E309 is safe and approved globally — but so rarely used that approval is almost theoretical.
| 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 δ-tocopherol was too limited” | Not a safety concern; just need more data |
| Food-Info.net | Approved with guidance | Up to 2 mg/kg body weight/day | Most restrictive of tocopherols |
| JECFA (WHO) | Approved | ADI 0.15-2 mg/kg | Ongoing approval |
| FDA (US) | GRAS (Generally Recognized As Safe) | No safety concerns | Approved |
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 | 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 | ~3% of alpha-tocopherol; extremely low | Very weak as vitamin but safe |
| Overall Assessment | EFSA: “Not of safety concern”; Approval maintained | Safe but impractical for food use |
Why “Too Limited Dataset”?
EFSA’s statement that E309 has “too limited dataset” reflects reality:
– NOT unsafe: All available data show NO adverse effects
– Limited use: So rarely used that less food safety data exists
– Fewer studies: Much less research than E307
– No safety concern: But more data would strengthen confidence
– Approval maintained: Doesn’t mean unsafe; just less documented
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. For E309 specifically:
– Food-Info.net guidance: Up to 2 mg/kg bw/day
– Typical consumption from E309: Essentially zero (never used)
– This limit is theoretical due to minimal real-world use
E309 vs. E307: Understanding the Vast Difference
| Property | E307 (Alpha-Tocopherol) | E309 (Delta-Tocopherol) |
|---|---|---|
| Vitamin E Activity | 100% (reference) | ~3% (EXTREMELY LOW) |
| Regulatory History | Extensive; well-studied | Too limited; minimal use |
| Food Use | Very common; widespread | Virtually never used |
| Antioxidant Potency | High; effective | Very low; ineffective |
| Flavor Impact | Minimal; food-safe | STRONG; prohibitive |
| Cost Efficiency | Cost-effective | Very expensive per unit activity |
| Practical Use | Standard choice | No practical reason to use |
| Safety | Extensively documented as safe | Safe but underdocumented |
Bottom line: E309 is so inferior to E307 in every practical respect that it’s essentially never used. Food manufacturers have zero reason to choose it.
Health Benefits (Theoretical)
In theory, E309 provides vitamin E benefits, but the reality is limited:
– Antioxidant protection: Theoretically yes, but so weak it’s negligible at food levels
– Immune function: Theoretically yes, but insufficient concentration in food
– Cardiovascular health: Theoretically yes, but potency too low to matter
– Practical nutrition contribution: Essentially zero (never used in food)
Key insight: E309’s theoretical health benefits are irrelevant because it’s never used in food. You will never consume E309 as a food additive.
The Bottom Line
E309 (Delta-Tocopherol) is an approved, safe vitamin E form that is virtually never used in food.
What you should know:
- It’s safe: EFSA found it “not of safety concern”; no documented health risks
- It’s almost never used: You will almost certainly never encounter E309 on a food label
- It’s the weakest tocopherol: Only ~3% vitamin E activity of alpha-tocopherol
- It has a strong flavor: Major barrier to food use; makes products taste bad
- It’s economically impractical: Inferior to E307 in every cost-benefit analysis
- Better alternatives exist: E307 and E306 are preferred in all practical applications
- It’s theoretical approval: Approved but almost never invoked due to minimal advantages
- Don’t worry about it: This is one food additive you can safely ignore