Fish oil for high cholesterol
Pro Research Analysisby 
Searched over 200M research papers
Fish Oil for High Cholesterol: A Comprehensive Review
Introduction to Fish Oil and Cholesterol Management
Fish oil, rich in omega-3 fatty acids, has been widely studied for its potential benefits in managing cholesterol levels and overall cardiovascular health. This article synthesizes findings from multiple research studies to provide a clear understanding of how fish oil supplementation affects cholesterol and other lipid parameters in individuals with hyperlipidemia.
Effects of Fish Oil on Triglycerides
Significant Reduction in Triglycerides
Several studies have consistently shown that fish oil supplementation leads to a significant reduction in fasting blood triglyceride (TG) levels. A meta-analysis of 47 studies found that an average daily intake of 3.25 grams of EPA and DHA resulted in a clinically significant reduction in TG levels by 0.34 mmol/L1. Similarly, a placebo-controlled trial demonstrated that fish oil lowered plasma triglyceride levels from 4.0 to 2.5 mmol/L in hypertriglyceridemic patients2. These findings suggest that fish oil is effective in reducing triglycerides, which is beneficial for cardiovascular health.
Effects on LDL and HDL Cholesterol
Increase in LDL Cholesterol
While fish oil is effective in lowering triglycerides, its impact on LDL cholesterol (LDL-C) is more complex. Multiple studies have reported an increase in LDL-C levels following fish oil supplementation. For instance, a study involving hypertriglyceridemic patients found that fish oil raised LDL-C levels from 3.7 to 4.25 mmol/L2. Another study in middle-aged men with hypercholesterolemia reported a 9.1% increase in LDL-C after fish oil supplementation5. This increase in LDL-C necessitates careful monitoring when using fish oil for lipid management.
Minimal Impact on HDL Cholesterol
The effect of fish oil on HDL cholesterol (HDL-C) appears to be minimal. The meta-analysis mentioned earlier found only a slight increase in HDL-C levels (0.01 mmol/L)1. Similarly, other studies have shown no significant changes in HDL-C levels with fish oil supplementation2 5. Therefore, while fish oil may not significantly boost HDL-C, it does not adversely affect it either.
Combined Effects with Other Supplements
Garlic and Fish Oil Combination
Combining fish oil with other supplements like garlic can mitigate some of the adverse effects on LDL-C. A study found that while fish oil alone increased LDL-C, the combination of garlic and fish oil significantly reduced both total cholesterol and LDL-C levels10. This combination also led to a substantial decrease in triglycerides, suggesting a synergistic effect that enhances the lipid-lowering benefits of fish oil.
Soy and Fish Oil Combination
Another study explored the combination of soy (kinako) and fish oil, finding that soy could attenuate the increase in LDL-C and total cholesterol induced by fish oil8. This combination also improved glucose metabolism, making it a potentially beneficial strategy for individuals with metabolic syndrome.
Special Considerations
Effects in Different Populations
The impact of fish oil can vary based on the population studied. For example, a study on rodents found that cetoleic acid-rich fish oils significantly lowered circulating total cholesterol3. In humans, a trial with saury oil, rich in omega-11 fatty acids, showed beneficial effects on LDL particle counts and HDL particle size4. These findings highlight the importance of considering specific types of fish oil and the population being treated.
Long-Term Benefits and Risks
While fish oil supplementation offers clear benefits in reducing triglycerides, the increase in LDL-C and the need for careful monitoring cannot be overlooked. Long-term studies are required to fully understand the cardiovascular outcomes associated with fish oil supplementation, especially in individuals with varying lipid profiles.
Conclusion
Fish oil supplementation is effective in significantly reducing triglyceride levels, which is beneficial for cardiovascular health. However, it tends to increase LDL cholesterol, necessitating careful monitoring and potentially combining it with other supplements like garlic or soy to mitigate this effect. Overall, fish oil remains a valuable tool in lipid management, but its use should be tailored to individual patient profiles and monitored for long-term benefits and risks.
Sources and full results
Most relevant research papers on this topic
Benefits of fish oil supplementation in hyperlipidemia: a systematic review and meta-analysis.
Fish oil supplementation significantly reduces fasting blood triglyceride levels in hyperlipidemic individuals, but does not significantly affect total, HDL, or LDL cholesterol levels.
Meta-Analysis
Highly CitedEffects of a low saturated fat, low cholesterol fish oil supplement in hypertriglyceridemic patients. A placebo-controlled trial.
Fish oil supplements can lower plasma triglyceride levels in hypertriglyceridemic patients, but monitoring of lipoprotein changes is necessary due to potential long-term benefits.
RCTHighly CitedEffects of diets containing fish oils or fish oil concentrates with high cetoleic acid content on the circulating cholesterol concentration in rodents. A systematic review and meta-analysis
Intake of cetoleic acid-rich fish oils and concentrates significantly lowers circulating total cholesterol concentration in rodents, suggesting potential as functional dietary ingredients or supplements to reduce the risk of developing cardiovascular disease in humans.
Meta-AnalysisSupplementation with saury oil, a fish oil high in omega-11 monounsaturated fatty acids, improves plasma lipids in healthy subjects.
Saury oil supplementation is well-tolerated and improves cardiovascular parameters like LDL particle counts, HDL particle size, and plasma TG levels in healthy individuals.
RCTFish oil supplementation does not lower plasma cholesterol in men with hypercholesterolemia. Results of a randomized, placebo-controlled crossover study.
Fish oil supplements do not lower plasma cholesterol levels in middle-aged men with hypercholesterolemia without elevated triglycerides, and should not be recommended as a method to lower cholesterol in these patients.
RCTEffects of varying dietary fat, fish, and fish oils on blood lipids in a randomized controlled trial in men at risk of heart disease.
Fish or fish oil with a 40%-fat diet improves blood lipids, while a 30%-fat diet reverses negative effects of omega-3 fats on cholesterol.
RCTHighly CitedFish Oil Supplementation Alleviates the Altered Lipid Homeostasis in Blood, Liver, and Adipose Tissues in High-Fat Diet-Fed Rats.
Fish oil supplementation improves lipid metabolism in blood, liver, and adipose tissues in high-fat diet-fed rats, reducing cholesterol and triglyceride levels.
Effect of soy product kinako and fish oil on serum lipids and glucose metabolism in women with metabolic syndrome.
Kinako, a soy product, can moderate the adverse effects of high doses of fish oil on LDL cholesterol, total cholesterol, and glucose metabolism levels in women with metabolic syndrome.
RCTFish Oil Supplements Lower Serum Lipids and Glucose in Correlation with a Reduction in Plasma Fibroblast Growth Factor 21 and Prostaglandin E2 in Nonalcoholic Fatty Liver Disease Associated with Hyperlipidemia: A Randomized Clinical Trial
Fish oil supplements can improve metabolic abnormalities in nonalcoholic fatty liver disease associated with hyperlipidemia by reducing fibroblast growth factor 21 and prostaglandin E2.
RCT
Rigorous JournalHighly CitedEffect of garlic and fish-oil supplementation on serum lipid and lipoprotein concentrations in hypercholesterolemic men.
Garlic and fish-oil supplementation effectively lowers total cholesterol and LDL-C levels in hypercholesterolemic men, with the combination providing a more beneficial effect on serum lipid and lipoprotein concentrations.
RCTHighly Cited