Shark Liver Oil Boosts Brain Health & Lowers Inflammation? (Study)

observational-study PMID: 34146594

Quick Summary: A small study found that taking shark liver oil increased levels of important fats called plasmalogens in the blood. This also helped lower levels of unhealthy cholesterol, fats, and inflammation markers in overweight men.

What Are Plasmalogens & Why Do They Matter?

Plasmalogens are fats found in your body's cells, especially in the brain, heart, and immune cells. They play a key role in cell health and function. Think of them as protectors for your cells. Lower levels of plasmalogens have been linked to problems like heart disease, Alzheimer's, and other health issues.

What The Research Found

Researchers looked at how shark liver oil affected plasmalogen levels and other health markers. They found:

Increased Plasmalogens: Taking shark liver oil significantly boosted plasmalogen levels in the blood.

Lowered Unhealthy Fats: Shark liver oil helped reduce levels of:

Triglycerides (a type of fat in the blood) by about 16%.
Total free cholesterol by about 8%.

Reduced Inflammation: The study also showed a decrease in C-reactive protein (CRP), a marker of inflammation, by about 25%.

Study Details

Who was studied: 10 overweight or obese men.

How long: Each participant took either shark liver oil or a placebo (dummy pill) for 3 weeks, then switched to the other for another 3 weeks.

What they took: Participants took 4 grams per day of a purified shark liver oil supplement called Alkyrol®.

What This Means For You

This study suggests that shark liver oil might help improve your health by:

Boosting Brain Health: Increasing plasmalogen levels could support brain function.

Improving Heart Health: Lowering unhealthy fats and inflammation is good for your heart.

Reducing Inflammation: Less inflammation can help protect against many diseases.

Important Note: This was a small study. More research is needed to confirm these findings and see if they apply to everyone.

Study Limitations

Small Study Size: Only 10 men were involved, so the results might not apply to everyone.

Limited Group: The study only included overweight or obese men.

Short Duration: The study lasted only a few weeks.

Specific Supplement: The study used a specific brand of shark liver oil (Alkyrol®). Other brands might have different effects.

No Clinical Outcomes: The study did not assess clinical endpoints (e.g., cardiovascular events).

Bottom Line: While this study is promising, more research is needed before we can say for sure that shark liver oil is a reliable way to boost plasmalogens and improve health. Talk to your doctor before taking any new supplements.

Key Findings

Shark liver oil (SLO) supplementation significantly increased endogenous plasmalogen levels in plasma and white blood cells while reducing key metabolic and inflammatory markers. Specifically, SLO (as Alkyrol®) elevated plasmalogen concentrations (p<0.05), decreased plasma triglycerides by 15.8% (p=0.008), total free cholesterol by 8.3% (p=0.019), and C-reactive protein (CRP) by 24.7% (p=0.031). The study concluded that SLO-derived alkylglycerols enhance plasmalogen synthesis, potentially mitigating dyslipidemia and inflammation in overweight/obese individuals.

Study Design

This was a randomized, double-blind, placebo-controlled crossover trial. Ten overweight or obese adult males (mean BMI: 31.2 kg/m²) completed the study. Participants received either 4 g/day of purified SLO (Alkyrol®) or methylcellulose placebo for 3 weeks, followed by a 3-week washout period, then crossed over to the alternate treatment for another 3 weeks. Primary outcomes measured changes in plasma/cellular lipidomes and metabolic/inflammatory biomarkers.

Dosage & Administration

Participants ingested 4 grams per day of Alkyrol® (a purified shark liver oil supplement standardized for alkylglycerols) or an identical-appearing methylcellulose placebo capsule. Supplementation occurred daily for two separate 3-week intervention periods, separated by a 3-week washout phase.

Results & Efficacy

SLO significantly increased plasmalogen levels in plasma and circulating white blood cells (p<0.05 for multiple species). Statistically significant reductions were observed in:
- Triglycerides: -15.8% (p=0.008)
- Total free cholesterol: -8.3% (p=0.019)
- C-reactive protein (CRP): -24.7% (p=0.031)
No significant changes occurred in the placebo phase. All p-values indicate statistical significance at the conventional α=0.05 level, though exact confidence intervals were not provided in the summary.

Limitations

Major limitations include the very small sample size (n=10), exclusive focus on males, short intervention duration (3 weeks per phase), and inclusion of only overweight/obese participants without diagnosed metabolic disease. The study did not assess clinical endpoints (e.g., cardiovascular events), and results may not generalize to females, healthy-weight individuals, or other populations. Alkyrol® is a specific branded product, limiting applicability to other SLO sources. Lack of dietary/activity monitoring introduces potential confounding.

Clinical Relevance

This study provides preliminary biochemical evidence that SLO supplementation may increase plasmalogen levels and improve lipid/inflammatory markers in overweight/obese men. However, the small scale and short duration mean these findings do not support clinical recommendations for SLO use. Users should note this demonstrates mechanistic potential only—not proven therapeutic benefit for metabolic disease. Future larger, longer trials in diverse populations with clinical endpoints are needed before considering SLO for metabolic health applications. Current evidence remains insufficient for supplement guidance.

Shark Liver Oil Boosts Brain Health & Lowers Inflammation? (Study)