Omega-3 fatty acids are “healthy fats” that may support your heart health. One key benefit is helping to lower your triglycerides. Specific types of omega-3s include DHA and EPA (found in seafood) and ALA (found in plants). Some foods that can help you add omega-3s to your diet include fatty fish (like salmon and mackerel), flaxseed and chia seeds.
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Omega-3 fatty acids (omega-3s) are polyunsaturated fats that perform important functions in your body. Your body can’t produce the amount of omega-3s you need to survive. So, omega-3 fatty acids are essential nutrients, meaning you need to get them from the foods you eat.
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The two main types of fatty acids are saturated fat and unsaturated fat. Unsaturated fat further breaks down into polyunsaturated fat and monounsaturated fat. These are terms you commonly see on nutrition labels.
Fatty acids are chain-like chemical molecules made up of carbon, oxygen and hydrogen atoms. Carbon atoms form the backbone of the chain, with oxygen and hydrogen atoms latching on to available slots.
A saturated fat has no more open slots. A monounsaturated fat has one open slot. A polyunsaturated fat has more than one open slot.
Saturated fats are sometimes known as “bad” or “unhealthy” fats because they increase your risk of certain diseases like heart disease and stroke. Unsaturated fats (polyunsaturated and monounsaturated) are considered “good” or “healthy” fats because they support your heart health when used in moderation.
Omega-3s, as a form of polyunsaturated fat, are healthier alternatives to saturated fat in your diet.
Omega-3 fatty acids help all the cells in your body function as they should. They’re a vital part of your cell membranes, helping to provide structure and supporting interactions between cells. While they’re important to all your cells, omega-3s are concentrated in high levels in cells in your eyes and brain.
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In addition, omega-3s provide your body with energy (calories) and support the health of many body systems. These include your cardiovascular system and endocrine system.
There are three main types of omega-3 fatty acids:
Omega-3s are essential nutrients that you need to get from your diet. When you get ALA from food, your body is able to turn some of the ALA into EPA and subsequently to DHA. However, this process provides just a small amount of EPA and DHA. So, dietary sources of EPA and DHA (like fish) are essential.
Omega-3 fatty acids have many potential benefits for your cardiovascular health. One key benefit is that they help lower your triglyceride levels. Too many triglycerides in your blood (hypertriglyceridemia) raises your risk of atherosclerosis, and through this, can increase your risk of heart disease and stroke. So, it’s important to keep triglyceride levels under control. In addition, omega-3s may help you by raising your HDL (good) cholesterol and lowering your blood pressure.
Some studies show omega-3s may lower your risk for:
Beyond heart health, omega-3s may help lower your risk of developing:
Research continues to investigate these and other possible benefits.
Omega-3 fatty acids may lower your cardiovascular disease risk when you consume them as part of your diet. In general, it’s better to opt for food sources (like fish) rather than pills.
Omega-3 dietary supplements (fish oil pills) may have some benefits for select individuals. But it’s best to proceed with caution. When it comes to fish oil pills, it’s important not to self-prescribe. Never take over-the-counter (OTC) supplements without talking to your healthcare provider first. Your physician, including your primary care provider or cardiologist, can prescribe you dietary supplements based on your risk characteristics and lipid levels. Some supplements, depending on their dosage, may:
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Plus, different supplements contain different formulations of omega-3 fatty acids. Some of these formulations don’t have proven benefits for your heart health. Research has shown the most promise with a specific formulation called icosapent ethyl (a purified form of EPA). This type of supplement may help people who meet all of these criteria:
Overall, clinical trials on omega-3 supplement benefits have mixed results. Some studies show omega-3 supplements help protect your heart, while others show no benefit. This may be due to variations in research methods (like dosage amounts, omega-3 formulations and the patients enrolled in the study).
As researchers continue to explore this topic, the dietary guidelines and recommendations may change. So, it’s important to have a conversation with your provider, who can offer tailored advice based on your needs and your medical history. The advice they provide will be the most accurate, up-to-date and scientifically backed information.
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Fish is the best dietary source of omega-3s. But you can also gain this essential nutrient from some plant-based foods.
Fish is the best source of omega-3s.
The chart below lists some types of fish that can add omega-3 fatty acids to your diet. The serving size for each type of fish listed is 3 ounces (oz.), with nutrient data provided by the U.S. Department of Agriculture. While some types of fish contain a small amount of ALA, the chart contains the total DHA and EPA content for consistency. These totals reflect the DHA and EPA content in raw (uncooked) fish, except where noted.
Type of fish (3 oz. serving) | Omega-3 content (DHA + EPA) |
---|---|
Mackerel | 2.0 grams |
Salmon (farmed, Atlantic) | 1.7 grams |
Herring (Atlantic) | 1.3 grams |
Anchovy | 1.2 grams |
Salmon (wild, Atlantic) | 1.2 grams |
Whitefish | 1.1 grams |
Tuna (Bluefin) | 1.0 grams |
Halibut (Greenland) | 0.8 grams |
Sardines (Atlantic, canned in oil) | 0.8 grams |
Tuna (Albacore, canned in water) | 0.7 grams |
Bluefish | 0.7 grams |
Striped bass | 0.6 grams |
Rainbow trout (wild) | 0.5 grams |
Tuna (light, canned in water) | 0.5 grams |
Type of fish (3 oz. serving) | |
Mackerel | |
Omega-3 content (DHA + EPA) | |
2.0 grams | |
Salmon (farmed, Atlantic) | |
Omega-3 content (DHA + EPA) | |
1.7 grams | |
Herring (Atlantic) | |
Omega-3 content (DHA + EPA) | |
1.3 grams | |
Anchovy | |
Omega-3 content (DHA + EPA) | |
1.2 grams | |
Salmon (wild, Atlantic) | |
Omega-3 content (DHA + EPA) | |
1.2 grams | |
Whitefish | |
Omega-3 content (DHA + EPA) | |
1.1 grams | |
Tuna (Bluefin) | |
Omega-3 content (DHA + EPA) | |
1.0 grams | |
Halibut (Greenland) | |
Omega-3 content (DHA + EPA) | |
0.8 grams | |
Sardines (Atlantic, canned in oil) | |
Omega-3 content (DHA + EPA) | |
0.8 grams | |
Tuna (Albacore, canned in water) | |
Omega-3 content (DHA + EPA) | |
0.7 grams | |
Bluefish | |
Omega-3 content (DHA + EPA) | |
0.7 grams | |
Striped bass | |
Omega-3 content (DHA + EPA) | |
0.6 grams | |
Rainbow trout (wild) | |
Omega-3 content (DHA + EPA) | |
0.5 grams | |
Tuna (light, canned in water) | |
Omega-3 content (DHA + EPA) | |
0.5 grams |
Some fish have higher levels of mercury than others. These are usually species of fish that mainly eat other fish, as their tissues accumulate mercury faster because of their diet. Some types of fish with the highest mercury levels include:
If you like to catch your own fish, check with local or state authorities to make sure fish caught from nearby bodies of water are safe for you to eat.
You should limit how often you eat fish high in mercury because too much mercury can lead to mercury poisoning. That condition can damage your brain, nervous system and other body systems. Some people are more sensitive to mercury or more prone to problems from it, so they shouldn’t eat these fish at all. Such groups include:
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Many types of fish are safe sources of omega-3s for people who are pregnant and for children when eaten in moderation (up to 12 ounces per week). These fish include:
Albacore (white meat) tuna has more mercury than canned light tuna. In general, you should eat no more than 6 ounces of Albacore tuna per week. If you’re pregnant or breastfeeding (chestfeeding), talk to your provider about the amount that’s safe for you.
There are several reasons why you can’t eat fish. You may be allergic, or you may follow a vegetarian or vegan diet. In these cases, you can look to certain plant-based sources of omega-3, which provide the nutrient in the form of ALA. Alternatively, you can speak with your provider about supplements like icosapent ethyl.
One of the best sources of ALA is ground or milled flaxseed. Aim to add about 2 tablespoons of it to your food throughout the day. Easy ways include sprinkling it in oatmeal, smoothies or yogurt.
Other sources of ALA include:
The amount of ALA you need depends on many factors, including your age and sex assigned at birth. Here are some general guidelines for adults:
Talk to your healthcare provider or a dietitian to learn ways to add ALA to your diet.
Ask your healthcare provider how much omega-3 you need. Research shows different benefits for different amounts depending on your medical history.
In general, the American Heart Association recommends people without a history of heart disease eat at least two servings of fish per week (6 ounces to 8 ounces total). If you have heart disease or high triglyceride levels, you may benefit from consuming even more omega-3 fatty acids. But it’s essential to talk to your provider about the amount that’s appropriate for you.
Select patients may not get enough omega-3 from their diet, and therefore they may benefit from taking fish oil supplements. However, researchers continue to look into when and how people should use these supplements. So, take them only under the guidance of a healthcare professional.
Talk to your healthcare provider if you have 3 grams or more of omega-3 fatty acids in your diet each day. High levels of these fatty acids can cause bleeding or other issues.
A note from Cleveland Clinic
It can be hard to keep up with the latest research on diet and nutrition. The advice your parents or grandparents followed may be vastly different from what we know to be true today. Like other medical research, studies on omega-3 fatty acids continue to uncover new insights. That means you might read articles that seem to offer conflicting advice, or you might have friends who tell you to take (or avoid) fish oil pills.
This is why talking to a healthcare provider is so important. Your provider knows you and your medical history best. They’re prepared to sift through the latest research and tell you what these findings mean for you. They’ll also give you individualized guidance on how to get the omega-3s your body needs.
Last reviewed on 11/17/2022.
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