Fish oil supplements reduce dialysis patients’ risk of heart attack and stroke by 43%

Cardiovascular disease remains the leading cause of death among kidney patients receiving dialysis, and effective prevention has been lacking. However, it now appears that higher intake of fish oil may reduce the risk of heart attack and stroke by as much as 43%. This is shown in a large placebo-controlled population study published in the New England Journal of Medicine. The researchers note that fish oil also benefits the cardiovascular system in the general population, and that it is especially the omega-3 forms EPA and DHA from fatty fish that have the beneficial effect.

The kidneys’ function is to filter waste products and toxins from the blood, which are excreted in the urine. The kidneys also regulate the body’s fluid and electrolyte balance, control blood pressure, and produce hormones such as EPO, which is necessary for the formation of red blood cells. Kidney failure is a serious condition in which the kidneys’ ability to perform these functions is significantly reduced or has ceased. If kidney failure occurs in an acute or chronic form, it may be caused by aging processes, reduced blood supply (for example due to shock), diabetes, enlarged prostate, kidney stones, severe infections, or environmental toxins.
If kidney function falls below 5%, it is necessary to cleanse the blood using dialysis. Over the past 10 years, the number of dialysis patients has doubled, and it is estimated that around 20% of them die each year. In the later stages of kidney failure, mortality is even higher. The life-threatening complications are primarily due to the fact that dialysis treatment can damage the cardiovascular system. The purpose of the new study was therefore to investigate whether higher intake of fish oil can reduce this side effect and prolong the lives of dialysis patients.

Fish oil supplements improve the cardiovascular system in several ways

The study was conducted as a double-blind, randomized, placebo-controlled trial at multiple sites in Canada and Australia and included 1,228 dialysis patients, who were divided into two groups. One group received fish oil supplements corresponding to 4 grams daily (including 1.6 grams of EPA and 0.8 grams of DHA). The other group received corn oil as an identical placebo, and no one knew who received what.
The purpose was to compare various outcomes in the two groups during the course of the study, including sudden or non-sudden death due to cardiovascular causes, heart attack, peripheral vascular disease leading to amputation, and fatal or non-fatal stroke. The researchers also examined other causes of death not related to cardiovascular function.
During a follow-up period of 3.5 years, the study revealed that the group receiving fish oil experienced the following significant improvements compared to the placebo group:

• Fewer serious cardiovascular events
• Fewer cases of fatal and non-fatal myocardial infarction
• Fewer cases of peripheral vascular failure leading to amputation
• Fewer fatal and non-fatal strokes
• Fewer deaths from all other causes

Overall, fish oil was able to reduce the risk of heart attack and stroke by as much as 43%. The researchers therefore conclude that patients undergoing dialysis have a significantly lower risk of developing serious and life-threatening cardiovascular conditions if they also receive fish oil supplements.
Fish oil also appears to benefit the cardiovascular system in the general population, and it is especially the omega-3 forms EPA and DHA from fatty fish that have the positive effect.
In any case, medical attention should be sought if kidney failure is suspected, as it can cause a variety of symptoms that may also occur in other conditions.

Various symptoms of kidney failure

• Fatigue
• Nausea
• Reduced appetite
• Itching
• Dizziness
• Increased urination at night
• Restless legs

Kidney failure, vitamin D deficiency, and depression

In the following article, you can read more about how many people with kidney failure also suffer from depression, and that vitamin D deficiency increases the risk.

• The connection between kidney disease, vitamin D deficiency, and depression

References:

Monash University. Omega-3 fish oil supplements cut attacks and strokes by 43 % in dialysis patients. ScienceDaily March 10, 2026

Charmaine E. Lok et al. Fish Oil Supplementation and Cardiovascular Events in Patients Receiving Hemodialysis. New England Journal of Medicine, 2026