Researchers studied over 3,800 people with heart disease to see if eating more omega-3 fatty acids (found in fish and certain oils) could help them live longer. They tracked these people for an average of 7.5 years and found that those who ate the most omega-3s had a lower risk of dying from any cause and specifically from heart disease. The study suggests that eating about 2 grams of omega-3s daily may be beneficial for people with existing heart conditions, though more research is still needed to confirm these findings.

The Quick Take

  • What they studied: Whether eating more omega-3 fatty acids (healthy fats from fish and plant sources) helps people with heart disease live longer and reduces their risk of dying from heart problems.
  • Who participated: 3,826 adults who already had heart disease, tracked for an average of 7.5 years using health records from a large U.S. national health survey.
  • Key finding: People who ate the most omega-3 fatty acids had a 23% lower risk of dying from any cause and a 37% lower risk of dying specifically from heart disease compared to those who ate the least.
  • What it means for you: If you have heart disease, eating more omega-3-rich foods may help you live longer, but this isn’t a replacement for medications or other treatments your doctor recommends. Talk to your healthcare provider about whether increasing omega-3 intake is right for your situation.

The Research Details

This was a prospective cohort study, which means researchers followed real people over time and tracked what happened to them. The scientists used data from the National Health and Nutrition Examination Survey, a large U.S. government health study that tracks thousands of Americans. They looked at people who had already been diagnosed with heart disease and measured how much omega-3 fatty acids they ate. Then they followed these people for several years (averaging 7.5 years) and recorded who died and what caused their deaths.

The researchers used a statistical method called Cox regression analysis to figure out if there was a connection between omega-3 intake and death risk. They adjusted their calculations to account for other factors that affect health, like age, smoking, exercise, and other medical conditions. This helps ensure that any differences they found were actually related to omega-3 intake and not just because some groups were healthier overall.

The study also used special statistical models to look at whether there was an ideal amount of omega-3 to eat—kind of like finding the “sweet spot” dose that provides the most benefit.

This type of study is valuable because it follows real people in their everyday lives rather than just testing something in a lab. Since heart disease is a serious condition and people with it need practical guidance, seeing what actually happens when people eat different amounts of omega-3s is more useful than just studying the chemical effects in isolation. The long follow-up period (7.5 years) also gives researchers time to see real health outcomes like death, which is more meaningful than just measuring blood markers.

Strengths: The study included a large number of people (3,826), had a long follow-up period, and adjusted for many other health factors that could affect the results. The findings were consistent across different statistical methods. Limitations: This study shows association (two things happening together) but cannot prove that omega-3s directly caused the lower death rates—other unmeasured factors could be involved. People who eat more omega-3s might also exercise more or have other healthy habits. The study relied on people remembering what they ate, which can be inaccurate.

What the Results Show

The main finding was that people with heart disease who ate the most omega-3 fatty acids had significantly better survival rates. Specifically, those in the highest group of omega-3 consumption had a 23% lower risk of dying from any cause compared to those eating the least. When looking specifically at heart disease deaths, the benefit was even larger—a 37% reduction in risk for those eating the most omega-3s.

The study also found that the relationship between omega-3 intake and survival wasn’t simply “more is always better.” Instead, there appeared to be an optimal amount: about 2.12 grams per day of total omega-3 fatty acids provided the most benefit. For one specific type of omega-3 called ALA (found in plant sources like flaxseed and walnuts), the optimal amount was about 2.03 grams per day.

The researchers created survival curves (graphs showing how many people in each group were still alive over time) that visually demonstrated the advantage of higher omega-3 intake. People eating more omega-3s consistently had better survival rates throughout the follow-up period.

When the researchers looked at different groups of people separately (by age, sex, and other factors), the benefits of omega-3s appeared fairly consistent across most groups, suggesting the finding wasn’t limited to just one type of person.

The study found that different types of omega-3 fatty acids showed similar protective effects. Both omega-3s from fish (EPA and DHA) and those from plant sources (ALA) were associated with lower mortality risk. The dose-response analysis revealed an interesting pattern: benefits increased as people ate more omega-3s up to a certain point (around 2 grams daily), but eating much more than that didn’t provide additional benefit. This suggests there’s an optimal range rather than a “more is always better” situation.

Previous research on omega-3s and heart health has shown mixed results. Some clinical trials found benefits, while others didn’t. This study adds important evidence by looking at real-world outcomes in people who already have heart disease. While some earlier studies focused on preventing heart disease in healthy people, this research specifically examined people with established heart conditions, which is a different and important question. The findings align with general medical consensus that omega-3s are beneficial for heart health, but this study provides more specific guidance about optimal intake amounts.

The study cannot prove that omega-3s directly cause longer life—it only shows they’re associated with it. People who eat more omega-3s might also have other healthy habits (exercise, better diet overall, medication adherence) that actually explain the benefits. The study relied on people reporting what they ate at one point in time, which may not reflect their typical diet. The research used data collected up to 2019, so it doesn’t include more recent information. Additionally, the study couldn’t account for all possible health factors that might influence outcomes. Finally, while the sample size was large, the results had some uncertainty (shown by the confidence intervals), meaning the true benefit might be somewhat smaller or larger than reported.

The Bottom Line

For people with heart disease: Consider increasing omega-3 intake to around 2 grams daily through diet (fish, walnuts, flaxseed, chia seeds) or supplements, but only after discussing with your doctor. This appears to be associated with better survival outcomes. For healthy people: Current evidence suggests omega-3s are beneficial for heart health as part of an overall healthy diet, though this study doesn’t directly address prevention. Confidence level: Moderate—the evidence is encouraging but not definitive. This should complement, not replace, prescribed medications and lifestyle changes your doctor recommends.

This research is most relevant for people who have already been diagnosed with heart disease, heart attack, stroke, or similar conditions. It may also interest people with risk factors for heart disease (high cholesterol, high blood pressure, diabetes). Healthy people without heart disease should focus on general heart-healthy eating patterns rather than specifically targeting omega-3 amounts. People with bleeding disorders or taking blood thinners should consult their doctor before significantly increasing omega-3 supplements.

If you increase omega-3 intake, you shouldn’t expect to feel dramatically different immediately. The benefits shown in this study appeared over years of consistent intake. You might notice improved energy or other subtle changes within weeks, but the major health benefits (reduced mortality risk) take months to years to develop. Consistency matters more than quick results.

Want to Apply This Research?

  • Track daily omega-3 intake in grams, aiming for 2-2.5 grams daily. Log specific sources: fish servings (salmon, mackerel, sardines), plant sources (walnuts, flaxseed, chia seeds), and any supplements. Include portion sizes to calculate actual grams consumed.
  • Set a daily goal of one omega-3-rich food: add a handful of walnuts to breakfast, include a fish serving at dinner twice weekly, or sprinkle ground flaxseed on yogurt. Start with one change and build from there rather than overhauling your diet at once.
  • Weekly review of omega-3 sources consumed and average daily intake. Monthly check-ins to assess consistency and adjust food choices if needed. Track any changes in energy, digestion, or other health markers you notice. Share data with your healthcare provider at regular appointments to ensure your approach aligns with your overall treatment plan.

This research shows an association between omega-3 intake and better outcomes in people with heart disease, but cannot prove cause-and-effect. These findings should not replace medical advice from your doctor or prescribed heart disease treatments. Before significantly increasing omega-3 supplements, especially if you take blood thinners or have bleeding disorders, consult your healthcare provider. This information is for educational purposes and should be discussed with your medical team to determine what’s appropriate for your individual situation.