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When is the best time to take fish oil?

Fish oil supplements have many health benefits and contain essential omega-3 fatty acids

Key takeaways

  • You should take fish oil supplements daily, but there is no evidence that taking them at a certain time increases or decreases their effectiveness.

  • Taking fish oil with food may help cut down on unwanted side effects like fishy burps and improve absorption.

  • High doses of fish oil may interfere with blood clotting, so consult a healthcare provider if you take blood thinners or have an upcoming surgery.

Fish oil supplements are a worldwide, multibillion-dollar industry, but their roots are in an unlikely place: Greenland. In the 1970s and ‘80s, researchers studied the island’s indigenous Inuit population. The Inuit had comparatively low death rates from heart disease despite a diet that was similar to Danish and American diets in terms of fat consumption. A closer investigation revealed the difference: The fat in the Inuit diet came largely from whale blubber and seal fat—in other words, fish oil.

Ever since the first clinical trials showing a link between fish oil supplements and heart health were published in the 1990s, research has unearthed many other health benefits. Fish oil contains essential omega-3 fatty acids, which play an important role in the structure of human cell membranes and have anti-inflammatory properties, according to the National Institutes of Health.

“Because our diet does not include food sources such as fish and seafood in adequate amounts,” says Joseph Maroon, MD, FACS, the vice chairman of the Department of Neurological Surgery and Heindl Scholar in Neuroscience at the University of Pittsburgh Medical Center, “the majority of our population is deficient in omega-3 fatty acids.” Because of that, many Americans turn to fish oil supplements to make up the difference.

Supplements can be tricky, and many people wonder how to find a quality product, how much to take, and when to take it. Read on to learn more about fish oil supplementation.

When is the best time to take fish oil?

Experts say it is important to take fish oil supplements regularly and with food (especially foods containing fat to help with absorption) to provide the most effective health benefits and have the lowest risk of side effects. However, there is no scientific evidence that fish oil is more effective when taken in the morning versus at night. There may be individual reasons why someone would prefer to take supplements at a specific time of day, though.

Here are a few factors to consider when determining when to take your daily dose of fish oil supplement.

Take it daily. Taking any supplement at the same time each day helps it become a habit, so you’re less likely to miss a dose. “As with any nutrient, fish oil needs to be continually provided to the body as it is used daily for metabolic functions,” Dr. Maroon says. You should pick a time when you’ll remember to take it, whether that’s in the morning or at bedtime.

Take it with meals. A past study found that a fat-containing meal may aid the body’s ability to absorb omega-3 fatty acid supplements. However, newer formulations of fish oil supplements are efficiently absorbed even when taking them without food

However, beyond aiding in absorption, taking fish oil capsules with food can reduce upset stomach, indigestion, and “fishy burps,” says Gregory Shearer, Ph.D., professor of nutrition and physiology at Penn State University.

Take it earlier in the day. The most common side effects of fish oil supplements are fishy burps and an upset stomach, but a small 2015 study did find that insomnia could be exacerbated. If you are worried about the medication interfering with your sleep, take it in the morning. Also, if you are prone to GI issues, such as acid reflux or GERD, you may want to take the supplement earlier so the burps or indigestion doesn’t prevent you from falling asleep.

Aside from if you are trying to get better z’s, when you take fish oil is not influenced by the reason you are taking the supplement. This means that the time of day doesn’t make a difference if you’re taking it for inflammation, to lower cholesterol and triglycerides, or any of the other numerous potential benefits of omega-3s.

How much fish oil should I take daily?

The National Institutes of Health: Office of Dietary Supplements considers 1.6 grams per day to be an adequate intake of omega-3 fish oil for adults ages 18 and older. For his patients, Dr. Maroon generally recommends 2 grams of high-quality fish oil containing docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) be taken daily.

How much fish oil you need depends largely on your diet. If you regularly eat fatty fish such as salmon, sardines, or mackerel, you may not need to take a supplement. If you don’t eat much seafood, you may be deficient in omega-3s.

RELATED: 9 health benefits of sardines

Like any nutritional supplement, fish oil is meant to fill a nutritional gap in the diet. Shearer and other experts caution against treating it as a “medicine.” While there is evidence it may help with certain chronic health conditions, ultimately, fish oil is “just one member of a healthy team of nutrients,” Shearer says.

Because dietary needs are so variable, it is always best to consult a healthcare provider before taking any supplement and ask what kind and amount is best for you. While it is very difficult to take too much fish oil, you may experience more severe side effects if you take a very high dose.

Who should not take fish oil?

Fish oil is generally safe for adults, but you should consult your pediatrician before giving it to children. If you are pregnant or breastfeeding, you should discuss fish oil with your OB-GYN, as the supplement’s safety is not well known.

You should also proceed with caution if you are taking blood thinners or similar medications. “At high doses, fish oil may alter the process of blood clotting,” Dr. Maroon says. That is why he advises that anyone taking blood thinners or medications that alter blood clotting get the okay from their healthcare provider before taking fish oil supplements.

Similarly, if you take fish oil, make sure to seek medical advice before any surgery or invasive procedure about whether you can continue to take omega-3 supplements or how close to the scheduled procedure you should stop.

Finally, anyone with a seafood allergy should be cautious about taking fish oil supplements. While the American College of Allergy, Asthma & Immunology notes that some small studies have found people with fish allergies to have little to no reaction to fish oil supplements—likely because the protein content in these supplements is believed to be minimal and denatured—the research is not rigorous enough. It’s best to consult an allergist first.

If you do have an allergic or adverse reaction to fish oil, immediately discontinue it and call a healthcare provider. Call 911 if you experience signs of anaphylactic shock, such as quick onset of difficulty breathing, reduced blood pressure, swelling of the face, lips, tongue or throat, or persistent abdominal pain or vomiting.

Bottom line: Take fish oil can when it works best for you

If you’re not seeing the results you want or experiencing unpleasant side effects from taking fish oil supplements, you can experiment with what time you take fish oil or whether you take it with food. If all else fails, consult your healthcare provider.