Cod Liver Oil
Top food source of vitamin D (1,360 IU per 1 tablespoon, 340% DV). Recommended serving: 1 tablespoon.
Why It Matters for Longevity
Top food source of vitamin D (1,360 IU per 1 tablespoon, 340% DV). Recommended serving: 1 tablespoon. Most concentrated single dietary source of vitamin D; critical for calcium absorption, immune regulation, and the cardiovascular and neurological health outcomes central to the Longevity Diet.. Meta-analysis of 25 RCTs (11,321 participants) showed vitamin D supplementation significantly reduced risk of acute respiratory infections, with the greatest benefit in individuals with baseline deficiency — immune protection directly relevant to longevity. (Martineau et al., BMJ (2017) — PMID 28202713) Cod liver oil provides both vitamin D3 and preformed vitamin A (retinol) in a naturally co-occurring ratio, with EPA and DHA omega-3s; this multi-nutrient combination supports anti-inflammatory, bone-protective, and neuroprotective longevity mechanisms simultaneously. (Traber et al., Advances in Nutrition (2019) — PMID 30715266)
How to Use It
Pairs well with lemon juice, orange juice. Use as a oil in your daily meals according to the Longevity Diet guidelines.
What to Pair It With
| Ingredient | Why | Tradition |
|---|---|---|
| lemon juice | See synergies | General culinary |
| orange juice | See synergies | General culinary |
Synergies
- Calcium-Rich-Foods (synergy): Vitamin D from cod liver oil is essential for intestinal calcium absorption and bone mineralization; consuming alongside calcium-rich foods (fortified plant milks, leafy greens) maximizes bone-protective effects. - Magnesium (synergy): Magnesium is required for the enzymatic conversion of vitamin D to its active form (1,25-dihydroxyvitamin D); cod liver oil's vitamin D efficacy is impaired without adequate magnesium status.
Flavor Profile
Taste: fishy, rich, slightly bitter. Aroma: strong fish oil, oceanic. Texture: liquid oil, viscous. Category: supplement / functional oil.
The Science
- Martineau et al., BMJ (2017) — PMID 28202713: Meta-analysis of 25 RCTs (11,321 participants) showed vitamin D supplementation significantly reduced risk of acute respiratory infections, with the greatest benefit in individuals with baseline deficiency — immune protection directly relevant to longevity. - Traber et al., Advances in Nutrition (2019) — PMID 30715266: Cod liver oil provides both vitamin D3 and preformed vitamin A (retinol) in a naturally co-occurring ratio, with EPA and DHA omega-3s; this multi-nutrient combination supports anti-inflammatory, bone-protective, and neuroprotective longevity mechanisms simultaneously. - Løvik et al., European Journal of Clinical Nutrition (2003) — PMID 12734543: Daily cod liver oil supplementation in a Norwegian cohort significantly improved 25-hydroxyvitamin D status and reduced inflammatory markers (CRP, IL-6) over 6 months, supporting its use as an anti-inflammatory longevity supplement. - Book claim (high confidence): Top food source of vitamin D (1,360 IU per 1 tablespoon, 340% DV). Recommended serving: 1 tablespoon.
Key Nutrients
| Nutrient | Per 100g | Notes |
|---|---|---|
| Vitamin D3 (cholecalciferol) | ~250 mcg (10,000 IU) | Highly bioavailable fat-soluble vitamin D3; absorbed with the oil's lipid matrix; raises serum 25(OH)D more effectively than D2; stored in adipose tissue. |
| Vitamin A (retinol) | ~30,000 IU | Preformed retinol; extremely bioavailable; caution: 1 tbsp provides ~4,500 IU — well below the 10,000 IU/day tolerable upper limit but warrants monitoring in high-dose supplement users. |
| EPA + DHA (omega-3 fatty acids) | Triglyceride form omega-3s are better absorbed than ethyl ester supplements; peak plasma levels 3–4 hours post-ingestion; anti-inflammatory, cardioprotective, neuroprotective. |