Life Extension Magazine®

Flask filled with fish oil omega-3 addresses metabolic syndrome

Fish Oil Fights Metabolic Syndrome

Nearly half of Americans over 60 have metabolic syndrome. Omega-3 fatty acids found in fish oil can decrease risk and reverse certain aspects of metabolic syndrome.

Scientifically reviewed by: Gary Gonzalez, MD, in August 2023. Written by: Marsha Mcculloch, RD.

Metabolic syndrome refers to a cluster of disorders including abdominal obesity, high blood pressure, low HDL cholesterol, high triglycerides and high blood sugar.1

In the United States, nearly half of people age 60 and older have this cluster of metabolic disorders.2

Individuals with metabolic syndrome are at a higher risk of developing type II diabetes and cardiovascular disease.3

Metabolic syndrome also increases the risk of dementia, non-alcoholic fatty liver, and eye diseases like cataracts.4-7

Research shows that fish oil rich in omega-3 fatty acids (EPA and DHA) can help address the causes of metabolic syndrome.8,9

Americans’ average dietary intake of EPA and DHA is low.10-12

Most Life Extension® readers supplement with about 2,000 mg of EPA + DHA each day from highly purified fish oil.

The Meaning of Metabolic Syndrome

Spilt fish oil capsule supporting HDL

Metabolic syndrome is defined as having at least three of the following five metabolic disorders:3

  • Abdominal obesity (a waist circumference more than 40 inches in men or 35 inches in women),
  • High fasting blood glucose (100 mg/dL or above),
  • High triglycerides (150 mg/dL or above),
  • Low HDL ("good") cholesterol (40 mg/dL or below in men or 50 mg/dL or below in women), and
  • High blood pressure (130/85 mm Hg or higher).

These metabolic abnormalities are closely linked with the underlying causes of insulin resistance and chronic, low-grade inflammation.7

Fish oil can help correct multiple elements of metabolic syndrome.

Combating Metabolic Syndrome

Though a healthy diet, weight control, and regular exercise are vital for reducing the risk of metabolic syndrome, fish oil can also play a role.13

Fish oil contains a blend of fatty acids.11

The omega-3 polyunsaturated fatty acids EPA (eicosapentaenoic acid) and DHA (docosahexaenoic acid) are the main components of fish oil.

Fish oil not only helps prevent metabolic syndrome—it can help reverse it.

When 39 overweight adults followed a healthy lifestyle program for five months, only the group that also took fish oil daily (providing 540 mg EPA and 360 mg DHA) had significantly reduced markers of metabolic syndrome.14

Fish oil helps prevent and reverse metabolic syndrome by addressing the individual components of the condition.

Fighting Obesity and Inflammation

Fish oil can aid in reducing obesity in several ways.

One human trial showed that daily intake of 700 mg-1,620 mg of DHA decreased body fat, including belly fat, in people with diabetes. A lower daily intake of DHA (380 mg-500 mg) wasn’t as helpful.15

In this randomized, controlled trial, 68 people with type II diabetes took DHA-rich fish oil or a placebo for two months.15

The fish oil group lost 0.5-1 inch from their waistline while the placebo group gained 0.5 inch.15

Fish oil also decreases the inflammation associated with obesity.

Excess body fat increases the production of inflammatory cytokines, including interleukin 1 beta (IL-1 beta), interleukin 6 (IL-6), and tumor necrosis factor-alpha (TNF-alpha).8

EPA and DHA provide building blocks for specialized pro-resolving mediators, including resolvins, protectins, and maresins. These omega-3 metabolites play a vital role in turning off inflammatory responses and promoting tissue repair.16-19

Targeting Insulin Resistance

Woman running on beach supplementing with fish oil

Insulin resistance is closely associated with metabolic syndrome.

Recently, researchers reviewed the effects of fish oil on diabetes in a meta-analysis of 30 human trials.20

Twenty of the studies (67%) showed at least one diabetes-related benefit from fish oil. This included significant decreases in fasting blood glucose and insulin resistance, compared to placebo.

In a pilot study, researchers gave 32 overweight adults with type II diabetes fish oil (1,440 mg EPA + 960 mg DHA) daily for two months.8

The subjects experienced a significant decrease in insulin resistance, compared to the start of the study. In addition, study participants showed reductions in pro-inflammatory cytokines.

Similarly, when 36 obese adults took fish oil (120 mg EPA + 860 mg DHA) daily for three months, their fasting insulin level and insulin resistance each dropped by about 13%. The placebo group had no improvement.21

What you need to know

A Metabolic Syndrome Solution from the Sea

  • Metabolic syndrome is a cluster of conditions including abdominal obesity, elevated fasting blood glucose, lipid abnormalities, and high blood pressure. Having metabolic syndrome increases risk for type II diabetes and cardiovascular disease.
  • EPA and DHA, the main omega-3 fatty acids in fish oil, can significantly decrease the risk of metabolic syndrome and even help reverse the condition.
  • One of the best-studied benefits of fish oil is lower triglycerides, which can reduce risk of heart disease.
  • In 2019, the FDA affirmed a new, qualified health claim for fish oil, noting that consumption of the omega-3 fatty acids EPA and DHA may reduce the risk of high blood pressure and coronary heart disease.
  • Americans generally consume only a fraction of the omega-3s needed to reduce these risks. Daily oral intake of concentrated fish oil containing at least 2,000 mg EPA + DHA can fill this gap.

Omega-3 Reduces Cardiovascular Disease

Doctor holding fish oil with heart rate below

One of the most widely recognized benefits of fish oil is lower triglycerides. This decreases risk of cardiovascular disease.22

A recent meta-analysis of 40 clinical trials showed that omega-3 supplementation is associated with significant reductions in the risk for cardiovascular disease death.23 Specifically, this study found that EPA+DHA supplementation is associated with a reduced risk of:

  • Fatal myocardial infarction (35%)
  • Myocardial infarction (13%)
  • Coronary heart disease events (10%)
  • Coronary heart disease mortality (9%)

The study, published in the Mayo Clinic Proceedings, concluded that supplementation with EPA and DHA reduced the risk of coronary heart disease, including heart attack.23

Fish oil containing both EPA and DHA fatty acids has been shown to reduce the risk of cardiovascular disease by lowering triglyceride levels and improving insulin sensitivity.9,24,25

The cardiovascular protection was greater with increases in omega-3 dosage. Increasing intake of EPA and DHA by 1,000 mg per day was associated with a reduction of 5.8% in the risk of cardiovascular events.23

Life Extension® readers have been advised for decades to supplement with at least 2,000 mg and higher of combined EPA and DHA to maximize health benefits plus ingest foods rich in omega-3s.

Protecting the Heart

In 2019, the FDA affirmed a new qualified health claim for fish oil, noting that consumption of the omega-3 fatty acids EPA and DHA may reduce the risk of high blood pressure and coronary heart disease.26

When blood pressure is elevated, the risks of heart attack, stroke, and heart failure sharply increase.27

Metabolic syndrome and insulin resistance compound the problem of high blood pressure in several ways:

  • High blood pressure interacts synergistically with high blood glucose and harmful lipid levels, worsening atherosclerosis.27
  • Insulin resistance limits the ability of blood vessels to dilate (widen) to promote healthy blood flow.28,29
  • Higher circulating levels of unhealthy fatty acids due to insulin resistance leads to blood vessel constriction and an increase in blood pressure.13

Animal and human studies suggest that omega-3s may inhibit atherosclerosis and help lower blood pressure in several ways.30

Fish oil has antioxidant, anti-inflammatory, and anti-clotting actions in blood vessels. It also promotes blood vessel dilation.30,31

Maximizing the Benefits of Fish Oil

Blood testing vial for cholesterol levels test

Dosage is key for optimizing the benefits of fish oil.

An easy way to determine if omega-3 blood levels are optimal is to take a simple finger-stick test, done at home, called the Omega-3 Index.

The test reflects dietary intake of omega-3s.21 An omega-3 index above 8% suggests a lower risk of cardiovascular disease.32


Woman stretching on the beach after inflammation

Omega-3 fatty acids found in fish oil can improve several components of metabolic syndrome, as well as the underlying causes of insulin resistance and chronic inflammation.

EPA and DHA are the main active ingredients responsible for the benefits of fish oil and are available in concentrated form.

Consuming at least 2,000 mg daily of EPA + DHA is usually needed to achieve the metabolic benefits of fish oil, including maintaining healthy triglycerides and blood pressure levels.

Preventing or reversing metabolic syndrome can reduce the risk of type II diabetes, cardiovascular disease, and other serious health conditions.

If you have any questions on the scientific content of this article, please call a Life Extension® Wellness Specialist at 1-866-864-3027.


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