Cod Liver Oil Benefits: Why I Take It Daily at 71

At 70 years old, on my relentless mission to live to 200 with The 200 Year Life Project, I'm always hunting for nutrient-dense additions that pack a serious punch against aging. That's why cod liver oil is a daily staple—I take one teaspoon straight (or in capsules when traveling) for its unbeatable combo of omega-3 fatty acids (EPA and DHA), vitamin A, and vitamin D. This isn't trendy fish oil; it's the real deal from cod livers, delivering anti-inflammatory power, heart protection, bone support, and immune resilience in one spoonful.

What Sets Cod Liver Oil Apart

Unlike regular fish oil (from fish bodies), cod liver oil comes from the livers of Atlantic cod, naturally rich in pre-formed vitamin A (retinol) and vitamin D3—nutrients many of us are deficient in, especially as we age and spend less time in the sun. A typical teaspoon provides around 1,000-4,500 IU vitamin A, 400-1,000 IU vitamin D, and 1-2 grams of omega-3s, depending on the brand

Proven Health Benefits

1. Health and Reduced Inflammation

The EPA and DHA omega-3s lower triglycerides, reduce blood clotting, and calm chronic inflammation—a driver of aging and disease. Large studies link omega-3 intake to lower risks of heart events and sudden cardiac death. Cod liver oil's anti-inflammatory effects may even outperform plain fish oil in some markers.

2. Bone and Immune Support from Vitamin D

Vitamin D is crucial for calcium absorption and bone density. Historical use prevented rickets; modern evidence ties higher intake to stronger bones in older adults and fewer fractures. It also bolsters immunity—vital for longevity.

3. Eye Health and Vision Protection

Vitamin A maintains eye moisture and may slow age-related macular degeneration. Combined with omega-3s, it supports retinal health.

4. Joint Pain Relief and Arthritis

Studies show reduced pain and stiffness in rheumatoid arthritis patients, thanks to anti-inflammatory omega-3s.

5. Brain and Mood Benefits

Omega-3s support cognition and may ease depression/anxiety symptoms by boosting BDNF and serotonin. Emerging links to lower dementia risk.

6. Wound Healing and Skin Vitality

Topical and oral use accelerates healing; vitamins A and D promote skin repair.

The Research Behind This

Harris et al., Nature Communications, 2021 — pooled analysis of 17 prospective cohorts, 42,466 people followed for an average of 16 years. Those in the top 10 percent for blood EPA and DHA had roughly 13 percent lower all-cause mortality than those in the bottom 10 percent, with similar reductions for cardiovascular and cancer death.
UK Biobank analysis, Mayo Clinic Proceedings — circulating DHA was inversely associated with all-cause and cause-specific mortality in a much larger sample.

The important distinction. These studies measure omega-3 levels in your blood, not supplement taking. Your omega-3 index is a marker, and it is one of the few blood markers that tracks reliably with how long people live. That is why I test it rather than assume the capsules are working.

It also means these are observational findings. People with high omega-3 levels may differ in other ways. What is fair to say is that being low is a risk marker worth correcting, not that swallowing fish oil is proven to extend life.

How I Use Cod Liver Oil in My 200-Year Protocol

I take about 1 teaspoon daily (fermented or high-quality liquid for best absorption)—often in the morning with my other fats like Extra Virgin Olive OIL and MCT. It's listed in my public stack at garyleland.com/my-protocols/.

Choose third-party tested brands (low mercury, no rancidity) and flavored if the taste bothers you. Start low to avoid fishy burps.

Disclaimer: Potent stuff—high vitamin A can be toxic in excess; avoid if pregnant or on certain meds. Consult your doctor. This is my experience, not medical advice.

Cod liver oil is old-school wisdom meets modern science: A simple teaspoon fueling heart, bones, brain, and immunity for the long haul. Grandmas were onto something.

Do you take cod liver oil? What's your brand or dose? Share below—let's optimize together!

There is more on this in my full supplement stack.

If you want the rest of what I do, my full daily regimen is in my protocols, the training side is under fitness, every number I track is in test and stats, and the products I actually use are on my discount codes page.

Stay sovereign, stay healthy,
Gary

A note from Gary: I am not a doctor, and I am definitely not your doctor. I am a 71-year-old man running a 129-year experiment on himself in public. Nothing here is medical advice. Talk to your physician before changing anything.

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