Back in 2018 I did a webinar on fish oil. There was some negative press about fish oil back then saying that it was useless and not worth spending money on. Fast forward 6 years and sales of fish oil from many stores is still going strong. In this blog I will get you up to speed on the latest scientific studies showing the benefits of fish oil for cardiovascular health. And yes, fish oil is still good for your heart and whole cardiovascular system. Fish oil is a medicinal food whose main benefit is longevity.
The Old News: Fish Oil is Good for Your Heart
Back in 2018 I reviewed the results of a few studies that explored the relationship between omega-3 fatty acids and heart health. The Harris et al. (2017) study found that having a higher Omega-3 Index (above 8%) was linked to a roughly 30% lower risk of fatal coronary heart disease (CHD) compared to those with a lower index. Del Gobbo et al. (2016) analyzed data from 19 studies and found that higher levels of omega-3 fatty acids, particularly EPA, DPA, and DHA, were associated with a lower risk of fatal heart disease. Also, in a study of heart failure patients a slightly higher level of EPA was associated with an 8% lower rate of death. Lastly, Harris et al. (2018) showed that higher red blood cell levels of EPA and DHA were linked to a 34% lower risk of all-cause mortality and 39% lower occurrence of cardiovascular disease over a follow-up period of 7 years in the Framingham Heart Study. Overall, these studies suggest that increasing omega-3 fatty acid levels may help reduce the risk of dying from heart-related issues.
New Studies Looking at Omega 3 Index, Not Just Supplement Amounts
As convincing as these studies may seen, there have been more investigations of fish oil and heart disease in various populations. Scientists gradually have learned not to just measure how much fish oil people consumed, but also to look at blood levels of EPA and DHA to see if protective levels were achieved by their interventions. This is where the Omega 3 Index is helpful. The Omega 3 Index is the sum of EPA and DHA lipids in the membranes of red blood cells, which reflects long-term consumption of fats, not just what was eaten yesterday. Generally, a level of 8% is a protective level on the Omega 3 Index, while a level less than 4% has been shown to be high risk for cardiovascular events like sudden death.
Higher Omega 3 Index Helps Diabetics
The study of the NHANES nationally-representative population (1999-2014) by Jing Xie and colleagues looked at how omega-3 intake affects people with diabetes. They found that higher omega-3 intake (especially EPA and DHA) was linked to about a 25% lower risk of dying from any cause.
Higher Omega 3 Index Stops Progression of Coronary Artery Plaque
Alfaddagh and colleagues studied patients who already had coronary artery disease who were taking statin drugs. The study group was given 3.36 g of EPA + DHA per day. They found that those patients that achieved an Omega 3 Index greater than 4%, regardless of whether they took the supplement or not, did not have progression of coronary artery plaque. So, it wasn't just how much fish oil a person takes, but how much they absorb and incorporate into their body that makes a difference.
Higher Omega 3 Index Keeps CKD Patients Alive Longer
Chronic kidney disease heightens a person's risk of early death, especially from cardiovascular disease. In a study by Li and coworkers, also of the NHANES (1999-2014) cohort, the chronic kidney disease patients with the highest amount of omega 3 fat intake (EPA + DHA) had a 33% lower risk of death from any cause during 8 years of follow-up.
New Review: Circulating DHA Keeps People Alive Longer
A recent study and meta-analysis published in 2024 found that in 18 prospective studies including more than 160,000 people there was a 17% reduction in all cause mortality, 21% reduction in risk of cardiovascular disease mortality and a 17% reduction in cancer mortality for those with the highest levels of circulating DHA.
Higher Omega 3 Index Helps Prevent Second Heart Attack
In the OMEGA-REMODEL randomized controlled trial people were given 4 g/day of fish oil for 6 months after having a heart attack. They were then followed for 6 years to see if the fish oil had any effect. (To me this trial design seems strange, as you should just keep on taking fish oil to maintain the benefits. The benefits of almost every nutrient disappears gradually after you stop taking it.) Nevertheless, the researchers did find some benefit for those who did initially have more than a 5% increase in their omega 3 index score. They had less than half as many major cardiovascular events as those who didn't have a good response to taking fish oil.
Highest Omega 3 Index Can Cut Risk in Half of Sudden Death by Heart Attack
Thomas A. Zelniker and colleagues at the Harvard School of Medicine and Brigham and Women's Hospital found that higher omega-3 levels were linked to a significant reduction in cardiovascular risks in a case-cohort study in the MERLIN-TIMI 36 study group. Specifically, patients with higher plasma levels of EPA, DPA and DHA had a 51% reduction in risk for cardiovascular death and a 63% reduction in risk for sudden cardiac death. So, omega 3 fats can be protective even if you do have a cardiac event, so that you don't die unexpectedly.
Low Omega 3 Index Contributes to Peripheral Artery Disease
A recent study looked at the risk of peripheral artery disease (PAD) and omega 3 fats. PAD usually affects the circulation in the legs, with plaque causing less circulation in the lower extremities, leading to pain and cramping while walking, climbing stairs or vigorous activity that increase the need for oxygen in the muscles. A one percent decrease in the Omega 3 Index was associated with 39% increase in risk of PAD in a cross-section study of vascular surgery outpatients (not necessarily the healthiest people around if they require surgery of some sort). Control subjects had a Omega 3 Index of 6.0 ± 1.6% while PAD patients had an Omega 3 Index of 5.0 ± 1.7%. While 6.0% is good, it is still not in the optimal range.
Fish Oil Helps Lower Blood Pressure
Young people don't have much risk of immediate death from cardiovascular disease, as chronic disease get worse slowly. After all, age is definitely the strongest risk factor for all diseases and death itself. But elevated blood pressure can still be an issue for young people. And omega 3 fats can help. A cross-sectional study by Mark G. Filipovic and colleagues found that higher omega-3 levels were linked to lower blood pressure in young adults. The study involved 2,036 participants aged 25–41, and it showed that those with higher omega-3 had systolic and diastolic blood pressure that was about 4 mmHg and 2 mmHg lower, respectively. It doesn't sound like much of a decrease, but if the whole population does this it leads to a lot less high blood pressure across the entire population.
A review published in 2022 also agrees that fish oil lowers blood pressure. After crunching the numbers from 71 trials and almost 5,000 subjects, between 2 and 3 grams of EPA + DHA a day seemed to be optimal for lowering blood pressure.
How Much Fish Oil Do I Need to Take?
So, how much fish oil is needed to get to a protective level of the Omega 3 Index? Of course, it varies between people so that if you really want to know you should get a test kit from OmegaQuant and find out. But here are some guidelines from studies that asked this question.
Nayda and coworkers reviewed 17 clinical trials to get this answer. They found that doses between 1.8 and 3.4 grams per day for 3 to 6 months or 4.4 grams for 1 to 6 months were the most effective doses for people with heart disease. Notice especially that just 1 gram of EPA + DHA was not part of their recommendation.
Big Guys Need More Fish Oil
The amount you need depends on body size. Big guys need more. Lust and coworkers examined American style football players, average weight 230 pounds, over a 27-week period while giving them 0, 2, 4, or 6 grams of DHA per day. Six grams a day would be equivalent to taking 8 capsules of our Professional Strength DHA every day, which would be a bit pricey. By 8 weeks the 6 g/day group had reached an Omega 3 Index greater than 8%. The 4 g/day group reached 8% by 11 weeks but peaked out about 1-2% lower on the Omega 3 Index scale compared to the 6 g/day group. The 2 g/day group was just a hair lower and slower than the 4 g/day group, and not quite enough for these large dudes.
So, what is a good way of doing this? If you are over 200 pounds you may need 4 grams or more of EPA + DHA per day on an ongoing basis to get into the optimal range. But for many people if you take 4 grams per day of long chain omega 3 fats for one month and then keep it at 2 grams per day you will likely be in the therapeutic range.
Here is what that would look like to get 4 grams EPA + DHA per day and then 2 grams per day for the three types of fish oil that we offer our customers:
- Professional Strength DHA (500 mg DHA and 250 mg EPA per capsule): You would take 5 capsules a day period for a month and then 3 capsules a day after that.
- Pharmax Finest Pure Fish Oil (1,410 mg EPA + DHA / teaspoon): You would need almost 3 teaspoons a day for a month and then 1.5 teaspoons a day after that.
- Nordic Naturals Arctic Cod Liver Oil (850 mg EPA + DHA / teaspoon): You would take almost 5 teaspoons a day for a month, then 2 large teaspoons a day after that.
Do you want to be sure it is working for you? There's a test for that. Just order a test kit from OmegaQuant to ensure that your regimen is working for you. It is a simple at-home test that could give you assurance that you are getting the protection that omega 3 fats promise.
for many people if you take 4 grams per day of long chain omega 3 fats for one month and then keep it at 2 grams per day you will likely be in the therapeutic range
Can I Get Too Much EPA and DHA?
Data from Japan indicates there are benefit to having an Omega 3 Index score even greater than 8%, like up to 11%, so there is no worry about getting too much when taking less than 8 grams of EPA and DHA a day.
Summary: Fish Oil is A Medicinal Food Whose Main Benefit is Longevity
The science on fish oil is still saying that fish oil is good for you. The data has been consistent now for a long time. From lowering risk of sudden death of a heart attack, to lowering blood pressure, to keeping chronic kidney disease patients alive longer, to keeping diabetic patients from cardiovascular disease, fish oil works. You might even say that fish oil is a medicinal food whose key benefit is longer, healthier life. It takes around 2 grams of EPA + DHA per day to really stay in the highest, protective score of the Omega 3 Index.