Here are four facts you may not know about fish:
1. Fish is high in cholesterol.
Touted as a health food, fish has a reputation for being heart-healthy. People who opt for fish to try to protect their hearts might not realize that fish is often high in cholesterol.
While a 3-ounce T-bone steak contains 70 milligrams of cholesterol, three ounces of shrimp contain 161 milligrams. Numerous studies have shown that dietary cholesterol consumption corresponds with an increased risk for artery blockage.
The good news is that by eliminating foods that contain cholesterol, like fish, and opting for naturally cholesterol-free plant foods, people can reduce both their cholesterol levels and their risk of heart disease. Research has shown that every 1 percent reduction in cholesterol can reduce heart disease risk by 2 percent.
2. Most of the fat in fish is not heart-healthy fat.
While fish does contain omega-3 fats, most of the fat in fish is not heart healthy. Between 15 and 30 percent of the fat in fish is actually saturated fat, which stimulates the liver to produce more cholesterol. High-fat foods are associated with poor heart health outcomes.
Fish is often celebrated for being low in fat, but this is often not the case: 52 percent of the calories in Chinook salmon come from fat. Plant foods, on the other hand, are often naturally low in fat. Only 2 percent of the calories in rice and 4 percent of the calories in beans come from fat. Research has shown that diets low in fat are best for preventing heart disease.
In 1990, Dean Ornish, M.D., demonstrated that a low-fat vegetarian diet is capable of reversing heart disease. He put patients with heart disease on a low-fat, plant-based diet, and in one year, 82 percent showed a measurable reversal of their coronary artery blockages.
3. Supplementing with fish oil may do more harm than good.
In recent years, fish oil has been hailed as a miracle cure for everything from heart disease to dementia. Many people supplement with fish oil to increase their intake of omega-3 fatty acids, which are important for maintaining cellular function. Unfortunately, studies have shown that most of the health claims associated with fish oil may be unfounded.
A comprehensive Journal of the American Medical Association analysis involving 20 studies and more than 68,000 patients showed no link between fish oil and heart health. Similarly, a study published in the New England Journal of Medicine reported that patients who supplemented with fish oil did not reduce their risk of heart disease.
Additionally, recent reports indicate no association between fish oil supplementation and the prevention or improvement of dementia symptoms. Research has even shown that omega-3 supplements may increase diabetes and prostate cancer risk. Fortunately, many plant foods contain alpha-linolenic acid or ALA, which is the only essential omega-3 fatty acid. Excellent sources of ALA include walnuts, soybeans, leafy greens, flaxseed, avocado, and broccoli.
By eating a diet rich in these foods, people can reap all the benefits of omega-3 fatty acids without any of the side effects associated with fish consumption. Research has even shown that women who follow vegan diets have higher levels of omega-3 fatty acids in their blood than those who consume diets rich in fish, meat, and dairy.
4. Fish are full of pollutants.
Because fish and shellfish live in increasingly polluted environments, toxins from the water accumulate in their bodies. Studies have shown that most of the fish throughout the world contain dangerously high levels of mercury.
Exposure to mercury, which is a toxic metal, has serious health consequences, including increased risk for cancer, heart disease, and even death. A recent study revealed a link between mercury exposure and diabetes. Among nearly 3,000 participants, those who consumed the most mercury over an 18-year period had a 65 percent greater risk for developing diabetes.
Fish also contain unsafe levels of polychlorinated biphenyls, which are dangerous chemicals that have been linked to neurological problems and birth defects in babies who have been exposed. A plant-based diet automatically reduces exposure to these toxins.