There are numerous health benefits of eating fish, ranging from salmon to sardines, Atlantic herring, to Atlantic mackerel. Fish is a low-calorie, zero-carb diet high in polyunsaturated fatty acids, a form of good fat that falls under important nutrients. It is also high in protein, vitamins, and minerals.
It's no surprise that fish consumption is on the rise. According to the latest numbers from the U.S. Department of Commerce's Fisheries of the United States report, Americans consumed an average of 16.1 pounds of seafood per person in 2018.
"Fish is absolutely a superfood," says Dawn Jackson Blatner, R.D.N., C.S.S.D., author of The Superfood Swap: The 4-Week Plan to Eat What You Want Without the C.R.A.P.
We've compiled a list of five potential adverse effects of eating fish.
You might experience... if you eat fish.
1. A reduced risk of heart disease.
Consuming at least two servings (175 grams or about 6 ounces) of an oily fish each week was associated with a lower risk of experiencing a major cardiovascular disease event (such as a heart attack or stroke) among those who have already been diagnosed with a heart condition, according to an analysis of four international cohort studies involving more than 191,000 adults from 56 countries.
According to these findings, the omega-3 fatty acids present in this type of fish can reduce a person's odds of having another cardiac episode—and possibly a fatal one—by about 17 percent, according to these findings, which were published in J.A.M.A. Internal Medicine on March 8, 2021.
"It's long been recognized that eating two meals of fatty fish per week will assist improve heart health by lowering the risk of strokes and sudden cardiac events," says Julie Upton, MS, RD, founder of the nutrition marketing and communications firm A.F.H. Consulting.
She says that the American Heart Association recommends eating two servings of fish per week (one serving being 3.5 ounces), with omega-3-rich fatty fish like salmon, sardines, trout, and albacore tuna being the top choices. "However, the majority of Americans fall far short of this recommendation," she claims.
Suppose your budget—or your taste buds—doesn't allow for a couple of servings of fish every week. In that case, she suggests taking a supplement of D.H.A. (docosahexaenoic acid) and E.P.A. (eicosatetraenoic acid), two forms of long-chain fatty acids.
In fact, according to a study published in Circulation (an American Heart Association scientific publication) in 2017, people with cardiovascular disease may be able to lengthen their lives by taking an omega-3 fish oil supplement regularly.
Upton says, "This decision should be taken in cooperation with a physician."
2. An improvement in brain health.
Fatty fish contains omega-3 fatty acids, which may help protect your brain. Researchers from Columbia University Irving Medical Center in New York discovered in a 2020 study that older women (on average 70 years old) with the highest levels of omega-3 fatty acids in their blood also had higher volumes of white matter in their brain (the area made up of millions of nerve fibers).
The brain scans of those who ate one to two meals of baked or broiled fish or shellfish per week were better. What is the explanation for this? The omega-3s likely induced an anti-inflammatory response, which aided the brain in combating aging-related damage and chemicals found in air pollution.
"Eating fish as part of a healthy lifestyle may help boost the amount of grey matter in the brain—the stuff linked to better memory and cognition," says Blatner. "I like to imagine my brain growing bigger and stronger every time I eat fish!"
3. Decreased depressive episodes.
You are, once again, what you consume. The authors of the study, from Australia's James Cook University, looked at the eating habits of individuals on two islands: one with fast food and one without. The researchers discovered some fascinating findings by evaluating the participants for sadness, inquiring about their dietary choices, and measuring their blood levels, published in the journal Nutritional Neuroscience.
For starters, islanders with access to fast food ate more processed foods, whereas those on the other island ate more fish. Younger participants who ate fast food frequently were more likely to be diagnosed with serious depression symptoms. The seafood eaters also had high amounts of depression-fighting omega-3s, according to the results of blood tests.
"There is mounting evidence that certain people who suffer from depression may be deficient in the omega-3 fats E.P.A. and D.H.A.," explains Katherine Brooking, MS, RD, co-founder of A.F.H. Consulting, a nutrition marketing, and communications agency.
She points out that prior studies looked into the link between omega-3s and brain health by examining the connection between persons who ate fish regularly and depression rates. "Depression rates were particularly low in nations where fish intake is high, such as Japan, Taiwan, and Hong Kong," she says.
4. Enhancement of sleep quality.
Salmon and sleep may be mutually beneficial. Over five months, researchers compared the sleep habits of men who ate Atlantic fish three times a week to men who were told to eat other protein sources, such as chicken or steak, in a study published in the Journal of Clinical Sleep Medicine.
The males in the fish group reported superior sleep quality and daily functioning after the trial. Vitamin D may have played a role in this outcome, according to the authors.
According to Upton, "mounting data suggests that E.P.A. and D.H.A. are also beneficial for increasing sleep length and quality." "It appears that omega-3 fatty acids affect melatonin production, which can help you sleep better."
5. Less inflammation in the joints.
According to results published in the journal Arthritis Care & Research, adding sardines to your diet may help alleviate your stiff knees. One hundred seventy-six participants completed a questionnaire about their daily diet for nearly a year. Volunteers with rheumatoid arthritis who reported eating fish at least twice a week had fewer symptoms (such as swollen or sore joints) than those who ate fish once a month or less.
In a press release, principal investigator Dr. Sara Tedeschi said, "If our findings hold up in further research, it shows that fish diet may lessen inflammation related to rheumatoid arthritis disease activity."