The answer to the question how many times a week should i eat fish is just as simple as it is complicated. It is a common assumption that eating fish several times a week is good for you. Fish are rich in protein and omega-3 fatty acids and are often considered a heart-healthy alternative to red meat. How Many Times A Week Should I Eat Fish? Eating fish is what everyone is telling you as a good practice for your diet. Fish is good for your health however, it’s not practical to eat all the time.
Fish: Friend or Foe?
Fears of contaminants make many unnecessarily shy away from fish.
Fish is a very important part of a healthy diet. Fish and other seafood are the major sources of healthful long-chain omega-3 fats and are also rich in other nutrients such as vitamin D and selenium, high in protein, and low in saturated fat. There is strong evidence that eating fish or taking fish oil is good for the heart and blood vessels. An analysis of 20 studies involving hundreds of thousands of participants indicates that eating approximately one to two 3-ounce servings of fatty fish a week—salmon, herring, mackerel, anchovies, or sardines—reduces the risk of dying from heart disease by 36 percent.
Eating fish fights heart disease in several ways. The omega-3 fats in fish protect the heart against the development of erratic and potentially deadly cardiac rhythm disturbances. They also lower blood pressure and heart rate, improve blood vessel function, and, at higher doses, lower triglycerides and may ease inflammation. The strong and consistent evidence for benefits is such that the Dietary Guidelines for Americans, the American Heart Association, and others suggest that everyone eat fish twice a week.
Unfortunately, fewer than one in five Americans heeds that advice. About one-third of Americans eat seafood once a week, while nearly half eat fish only occasionally or not at all. Although some people may simply not like fish, the generally low consumption is likely also caused by other factors, including perceptions about cost, access to stores that sell fish, and uncertainty about how to prepare or cook fish. Still others may avoid seafood because they worry that they—or their children—will be harmed by mercury, pesticide residues, or other possible toxins that are in some types of fish.
Should you forgo fish because of the contaminants they might carry? It’s a controversial topic that is often fueled more by emotion than by fact. Here’s what’s known about the benefits and risks of eating fish and other seafood:
- Known or likely benefits: In a comprehensive analysis of human studies, Harvard School of Public Health professors Dariush Mozaffarian and Eric Rimm calculated that eating about 2 grams per week of omega-3 fatty acids in fish, equal to about one or two servings of fatty fish a week, reduces the chances of dying from heart disease by more than one-third. Both observational studies and controlled trials have also demonstrated that the omega-3 fats in fish are important for optimal development of a baby’s brain and nervous system, and that the children of women who consume lower amounts of fish or omega-3’s during pregnancy and breast-feeding have evidence of delayed brain development.
- Possible benefits: Eating fish once or twice a week may also reduce the risk of stroke, depression, Alzheimer’s disease, and other chronic conditions.
- Possible risks: Numerous pollutants make their way into the foods we eat, from fruits and vegetables to eggs and meat. Fish are no exception. The contaminants of most concern today are mercury, polychlorinated biphenyls (PCBs), dioxins, and pesticide residues. Very high levels of mercury can damage nerves in adults and disrupt development of the brain and nervous system in a fetus or young child. The effect of the far lower levels of mercury currently found in fish are controversial. They have been linked to subtle changes in nervous system development and a possible increased risk of cardiovascular disease. The case for PCBs and dioxins isn’t so clear. A comprehensive report on the benefits and risks of eating fish compiled by the Institute of Medicine calls the risk of cancer from PCBs “overrated.”
How much fish should we eat?
A healthy, balanced diet should include at least 2 portions of fish a week, including 1 of oily fish. Most of us aren’t eating this much. A portion is around 140g (4.9oz).
However, for certain types of fish, there are recommendations about the maximum amount you should eat.
How much oily fish should I eat?
We should eat at least 1 portion (around 140g when cooked) of oily fish a week.
Oily fish usually have higher levels of pollutants than other types of seafood. For this reason, there are maximum recommendations for the number of portions some groups should be eating each week.
The following people should eat no more than 2 portions of oily fish a week:
- women who are planning a pregnancy or may have a child one day
- pregnant and breastfeeding women
This is because pollutants found in oily fish may build up in the body and affect the future development of a baby in the womb.
How much white fish should I eat?
You can safely eat as many portions of white fish per week as you like, except for the following, which may contain similar levels of certain pollutants as oily fish:
- sea bream
- sea bass
- rock salmon (also known as dogfish, flake, huss, rigg or rock eel)
Anyone who regularly eats a lot of fish should avoid eating these 5 fish, and brown meat from crabs, too often.
Even though shark and marlin are white fish, there is separate advice about how much of them you should eat:
- children, pregnant women and women who are trying to get pregnant should not eat shark, swordfish or marlin, because they contain more mercury than other fish
- other adults should have no more than 1 portion of shark, swordfish or marlin a week
Many shark and marlin species are endangered, so we should avoid eating these fish to help stop these species becoming extinct. See the sustainable fish and shellfish section below for more information.
How much shellfish should I eat?
Although it is recommended that regular fish-eaters should avoid eating brown crab meat too often, there is no need to limit the amount of white crab meat that you eat. There are no maximum recommended amounts for other types of shellfish.
Eating fish while trying to get pregnant, and during pregnancy and breastfeeding
Eating fish is good for your health and the development of your baby. However, pregnant and breastfeeding women should avoid some types of fish and limit the amount they eat of some others. This is because of the levels of mercury and pollutants that some fish can contain.
When pregnant, you can reduce your risk of food poisoning by avoiding raw shellfish and making sure that any shellfish you eat is cooked thoroughly.
Below is advice from the Scientific Advisory Committee on Nutrition (SACN) and the Committee on Toxicity about eating fish when trying to get pregnant, or when pregnant or breastfeeding:
Shark, swordfish and marlin: do not eat these if you are pregnant or trying to get pregnant. All other adults, including breastfeeding women, should eat no more than 1 portion per week. This is because these fish can contain more mercury than other types of fish, and can damage a developing baby’s nervous system.
Oily fish: all girls and women who haven’t been throught the menopause yet, including those trying for a baby, or who are pregnant or breastfeeding, should have no more than 2 portions of oily fish a week. A portion is around 140g.
Tuna: if you are trying for a baby or are pregnant, you should have no more than 4 cans of tuna a week or no more than 2 tuna steaks a week. This is because tuna contains higher levels of mercury than other fish. If you are breastfeeding, there is no limit on how much tuna you can eat.
These figures are based on a medium-sized can of tuna with a drained weight of around 140g per can and a 140g cooked steak.
Remember, tuna doesn’t count as oily fish. So if you’ve had a portion of tuna during the week, you can still have up to 2 portions (women) or 4 portions (men) of oily fish.
Unless your GP advises otherwise, avoid taking fish liver oil supplements when you’re pregnant or trying for a baby. These are high in vitamin A (retinol), which can be harmful to your unborn baby. Pregnant women are advised to avoid taking supplements that contain vitamin A.
Reasons You Should Be Eating More Fish
1. It Lowers Risk of Heart Disease
According to a review published in the American Journal of Cardiology, fish consumption is associated with a lower risk of fatal and total coronary heart disease. Fish is high in heart-healthy omega-3 fatty acids which can reduce inflammation, help protect your heart, and stave off chronic disease.
2. It Reduces Risk of Alzheimer’s Disease
Fish is also a dietary essential for your brain. According to a 2016 study published in the Journal of the American Medical Association, moderate seafood consumption was linked with a lower risk of Alzheimer’s Disease. The study found that those who consume fish regularly had more grey brain matter, which reduces brain shrinkage and deterioration that can lead to brain function complications. Although they noted that seafood consumption was also correlated with higher levels of mercury in the brain, it was not correlated with brain neuropathy.
3. It Can Help Lower Symptoms of Depression
This seafood is also amazing for your mental health. The Journal of Psychiatry & Neuroscience found that fish oil can help improve symptoms of depression when taken with a selective serotonin reuptake inhibitor (SSRI), a type of antidepressant. Although there are reports of fish oil decreasing symptoms of depression on its own, there still needs to be more research conducted to prove this claim.
4. It’s a Great Source of Vitamin D
According to The National Institutes of Health, fish are high in vitamin D, and are considered one of the best dietary sources for this essential nutrient. According to the NIH, vitamin D is beneficial for calcium absorption for bone health and growth. Because 70% of the U.S. population does not meet the Estimated Average Intake (EAR) of vitamin D every year, it will certainly be helpful if you add more of this nutrient-dense food to your diet.
5. It Helps Improve Vision and Eye Health
The Agency for Healthcare Research and Quality found that omega-3 fatty acids are beneficial to improving vision and eye health. This is because the brain and eyes are heavily concentrated in omega-3 fatty acids and need them to maintain their health and function, according to the AHRQ’s findings. Fish is one of the best sources of these good fats.
6. It Can Help You Sleep Better
If you have trouble falling or staying asleep, eating more fish may do the trick. According to a study published by The Journal of Clinical Sleep Medicine, increased consumption of fish improved quality of sleep for most subjects. Researchers suspect that this is due to fish’s high concentration of vitamin D, which aids in sleep, according to the study.
7. It Helps Fight Acne
Whether you have hormonal or adult acne, fish can help alleviate your skin. A study published by BioMed Central noted that fish oil is beneficial to clearing skin for people with moderate to severe acne.
8. It’s Helpful in Alleviating Rheumatoid Arthritis
If you suffer from rheumatoid arthritis, which is chronic inflammation of your joints, eating more fish can help alleviate the swelling and pain. The American College of Rheumatology found that higher consumption of fish actually lowers disease activity in rheumatoid arthritis.
9. It’s a Lean Meat
The American Heart Association noted that fish is a great source of protein without the high saturated fat content that many other types of meat have. The AHA recommends eating two servings of fish per week, preferably fatty fish, which have a higher omega-3 fatty acid content.
10. It Helps Lower Cholesterol
The Baylor University Medical Center Proceedings noted that the omega-3 fatty acids found in fish oil assist in lowering LDL levels (also known as “bad” cholesterol levels) in the body. The omega-3 fatty acids in fish are known to help lower cholesterol-building lipids in the blood, according to the university’s findings.
6 of the Healthiest Fish to Eat
According to Seafood Watch, here are six fish that are healthy for you and the planet.
1. Albacore Tuna (troll- or pole-caught, from the US or British Columbia)
Many tuna are high in mercury but albacore tuna–the kind of white tuna that’s commonly canned–gets a Super Green rating as long as (and this is the clincher) it is “troll- or pole-caught” in the US or British Columbia. The reason: Smaller (usually less than 20 pounds), younger fish are typically caught this way (as opposed to the larger fish caught on longlines). These fish have much lower mercury and contaminant ratings and those caught in colder northern waters often have higher omega-3 counts. The challenge: You need to do your homework to know how your fish was caught or look for the Marine Stewardship Council (MSC) blue eco label.
2. Salmon (wild-caught, Alaska)
To give you an idea of how well-managed Alaska’s salmon fishery is, consider this: Biologists are posted at river mouths to count how many wild fish return to spawn. If the numbers begin to dwindle, the fishery is closed before it reaches its limits, as was done recently with some Chinook fisheries. This close monitoring, along with strict quotas and careful management of water quality, means Alaska’s wild-caught salmon are both healthier (they pack 1,210 mg of omega-3s per 3-ounce serving and carry few contaminants) and more sustainable than just about any other salmon fishery.
3. Oysters (farmed)
Farmed oysters are good for you (a 3-ounce serving contains over 300 mg of omega-3s and about a third of the recommended daily values of iron). Better yet, they are actually good for the environment. Oysters feed off the natural nutrients and algae in the water, which improves water quality. They can also act as natural reefs, attracting and providing food for other fish. One health caveat: Raw shellfish, especially those from warm waters, may contain bacteria that can cause illnesses.
4. Sardines, Pacific (wild-caught)
The tiny, inexpensive sardine is making it onto many lists of superfoods and for good reason. It packs more omega-3s (1,950 mg!) per 3-ounce serving than salmon, tuna, or just about any other food; it’s also one of the very, very few foods that’s naturally high in vitamin D. Many fish in the herring family are commonly called sardines. Quick to reproduce, Pacific sardines have rebounded from both overfishing and a natural collapse in the 1940s.
5. Rainbow Trout (farmed)
Though lake trout are high in contaminants, nearly all the trout you will find in the market is farmed rainbow trout. In the US, rainbow trout are farmed primarily in freshwater ponds and “raceways” where they are more protected from contaminants and fed a fish meal diet that has been fine-tuned to conserve resources.
6. Freshwater Coho Salmon (farmed in tank systems, from the US)
Freshwater coho salmon is the first–and only–farmed salmon to get a Super Green rating. All other farmed salmon still falls on Monterey Bay Aquarium’s Seafood Watch “avoid” list for a few reasons. Many farms use crowded pens where salmon are easily infected with parasites, may be treated with antibiotics, and can spread disease to wild fish (one reason Alaska has banned salmon farms). Also, it can take as much as three pounds of wild fish to raise one pound of salmon. Coho, however, are raised in closed freshwater pens and require less feed, so the environmental impacts are reduced. They’re also a healthy source of omega-3s–one 3-ounce serving delivers 1,025 mg.