What you need to know about getting the most omega-3 effect out of omega-3 supplements. 

Now that you know why omega-3s are one of the top nutrients for head-to-toe health, I will summarize the best available science to “prescribe” the right dose for whatever ailment you have or don’t want to get and answer other omega-3 questions you may have.   

Based on information from trusted scientific sources, for most adults, I recommend eating 1000 mg. EPA/DHA daily.

Note: In this chapter, the “milligrams per day” advice means how many milligrams of EPA and DHA daily, not the “milligrams of fish oil,” since there are other omegas in fish oil.  

Here’s how I arrived at this number: 

How Much Omega-3s Do the Healthiest World Cultures Eat?

The Japanese – who enjoy the longest healthspan and lifespan in the world – eat an average of 700-1000 mg omega-3 EPA/DHA per day

What Dosages do the Top Scientists in the World Recommend? 

The following recommendations generally follow those of the International Society for the Study of Fatty Acids and Lipids (ISSFAL), The National Institutes of Health (NIH), the American Heart Association (AHA), and The Institute of Medicine.

The minimum daily dose of omega-3s is as follows:


  • Fish oil supplements: 500 mg. omega-3 EPA/DHA per 2000 calories consumed
  • Oily seafood:  12 ounces per week (this translates to around 600 mg. omega-3 EPA/DHA per day, depending on the species)
  • For persons with heart disease: 1,000 mg. omega-3 EPA/DHA daily

For infants and children, the minimum recommendation of 500 mg./2000 calories translates to:

  • Infants: 300 mg. omega-3 EPA/DHA per day
  • Children ages 2-3: 420 mg.
  • Children 3 and up: at least 500 mg. per day

 My Personal Recommended Daily Dose

I believe most healthy adults should shoot for 1000 milligrams of omega-3 EPA/DHA daily.    You can get this amount by eating: 

  • 12 ounces a week of safe seafood
  • 500-1000 milligrams of omega-3 EPA/DHA fish oil supplements daily, depending on how much seafood you eat.


The Institute of Medicine (IOM), a trusted group of health experts who advise government health agencies, now recommend an upgrade of the RDA from meaning the average daily nutrient intake level to prevent a deficiency, to the amount necessary to reduce the risk of chronic diseases of all age groups, meaning preventing serious illnesses such as heart attacks and stroke, and not just scaly skin.  This usually translates to higher daily doses.


The general recommendation of 500 mg. EPA/DHA per day per 2000 calories consumed is the minimum preventive medicine dosage.  Here’s a list of dosage ranges: 

1. For neurologic disorders (e.g. depression, bipolar):  According to the “more omegas the merrier” studies, take at least 2 grams (2,000 mg.) per day of EPA in a fish oil supplement.  To this, I wish to add: eat 12 ounces of oily fish per week. 

Depending on the severity of your diagnosis, your doctor may adjust the dose.  Neurologic studies have used dosages ranging from 2 to 6 grams of EPA/DHA per day, either EPA alone or EPA in combination with a lesser amount of DHA.  DHA-only did not show therapeutic improvement like EPA alone did.

2.  For cardiovascular disease.  The American Heart Association recommends that people who have CVD or have a high risk for CVD, eat at least 1000 mg. omega-3 EPA/DHA daily.  How much omega-3 EPA/DHA to take depends upon the type and severity of the heart problem you have. 

My personal recommendation is to eat six ounces of wild salmon four times a week.  Depending on the species of seafood, this would give you at least 1 gram (1,000-1,200 mg.) of omega-3 EPA/DHA per day.

Now, I realize many of you won’t go for that much fish and prefer fish oil supplements.  You could take 1,000 mg. of omega-3 EPA/DHA fish oil supplement per day, plus two six-ounce servings of oily fish per week, for a total of  2,000 mg. per day.  

For people with very high triglycerides levels, The American Heart Association recommends you take up to 4,000 mg. omega-3 EPA/DHA per day, which may lower high triglyceride levels by 30-40 percent.

3.  For “itis” illnesses.  The dosage varies according to your “itis.”  Generally, it’s 3-4 grams a day.  For arthritis, science suggests the 3+3 guideline: three grams a day for three months.  It often takes three months for people suffering from arthritis to experience the optimal omega-3 effect, after which the dosage can be tapered down.  


To improve the absorption of fish oil supplements, best to take them with a meal that contains healthy fats.


As an omega-3 newbie, I take omega-3 supplements, but I’m confused.  Some have only DHA, others DHA and EPA. Which is better?

For the past decade, scientists who study omega-3 fats have wondered which of the omega-3s  are more important – DHA or EPA, and whether it is okay to take a supplement of one but not the other.  Although DHA is present in brain tissue in much higher amounts than EPA, it’s vital to eat both. 

EPA supports brain health by enhancing blood vessel health and blood flow to brain tissue.  We know from studies that when you eat EPA the brain rapidly gobbles it up, so the brain must need it to protect itself from inflammation.  Again, when in doubt, take a tip from my favorite scientist, Mother Nature.  


Omega-3 EPA/DHA is naturally found in certain fish, such as sockeye salmon, in a 1:1.4 ratio, with DHA being slightly higher than EPA.  Even algae, one of the most abundant seafood that fish eat, contains both DHA and EPA.  In fact, most fish contain an EPA/DHA ratio of around 1:1 to 1:2.


Both EPA and DHA occur naturally in mother’s milk in a ratio that varies according to her diet.  When mom eats fish or takes fish oils containing various omega-3 EPA and DHA ratios her mammary glands sort out what’s right for mother and baby.  Breastmilk always contains both DHA and EPA, with slightly higher DHA.

So, if both EPA and DHA are in the fish that swim in the sea and the milk that mothers make, the perfect grow food for their precious babies, it seems prudent to conclude that we should eat both.

Some nutritional supplements, especially those intended for infants and children, contain DHA only, and that’s okay for two reasons.  First, in the early years, it seems that DHA is the preferred omega-3 because children are in the stage of rapid brain growth.  

Once upon a time, it was thought that only DHA was important because it is the omega-3 that is predominant in nervous tissue, such as the brain, which contains very little EPA.  Yet, studies by Joseph Hibbeln at the National Institutes of Health showed that when the blood-brain barrier is injured and needs healing, it’s EPA that comes to the rescue as part of the healing inflammation.   Also, the brain is a very vascular organ.  EPA is vital for vascular health.

If you choose to supplement with omega-3s, these insights can help you maximize your supplements to enjoy the omega-3 effect! 

This is an excerpt from The Omega Effect, written by Dr. Bill Sears. Used with permission.