How to Buy Sustainable and Healthy Fish

It's no secret that eating fish can be beneficial to your health. Research has shown that regular consumption of omega-3 fatty acids is linked to decreased inflammation and overall disease prevention, including a reduced risk of cancer. Including fish in your diet is associated with a decreased risk of heart disease as well. Yet, there seems to be an array of questions revolving around fish consumption, which can be quite confusing. Should you consume wild or farmed fish? Should you be concerned about contamination and mercury levels? There is even concern about sustainability, overfishing and environmental impact. Considering the confusion surrounding fish consumption, here is some information to help you get your facts straight so you can make the decisions that are right for you:

Get to know the source. Whether fish is wild or farmed, knowing its origin is the first step to understanding if it's abundant, sustainable and healthy. The Monterey Bay Aquarium Seafood Watch is a great resource for finding sustainable seafood choices. While their main goal is to protect the oceans and the life that lives within, they have your health in mind as well. There is an app available as a go-to resource and a list of sustainable, low-mercury healthy fish options. The site is updated regularly so the information is current.

[Read: 8 Easy Ways to Load Up on Healthy Omega-3 Fats .]

Buy local. This well-known concept with produce and livestock also applies to fish. Local fish is more environmentally friendly, as energy-extensive shipping is taken out of the equation. Seafood Watch offers a consumer guide for choosing sustainable fish choices by state as well. Local fish varieties may not be as familiar as those at the grocery store but they may be less expensive, more abundant and rich in good-for-you nutrients.

Understand sustainable fishing. When it comes to sustainability, there are pros and cons associated with both farmed and wild-caught fish. Fish farms provide half the seafood eaten in the U.S. Considering the increased demand for fresh fish, farming fish is one way to alleviate the overfishing of wild-caught fish. Wild fish are often caught using large nets, which can damage the ocean floor and catch unintended (and often wasted) species called bi-catch. These practices can be detrimental to the environment and fish population. Yet, pollution and disease associated with aquaculture or fish-farming also negatively affects the environment and can damage the wild fish population. Small, wild-caught fish are being caught in massive quantities to feed farm fish, which is contributing to the depletion of certain wild fish populations. To learn more, visit the Monterey Bay Aquarium Seafood Watch site, which has guides for finding fish that is sustainably farmed and/or harvested in the wild. Take home tip: If you buy wild or farmed fish, make sure it is sustainable.

[Read: What You Need to Know About Fat, Fish and Salt .]

The question of nutrient density. One of the reasons we consume fish is for the omega-3 fatty acids. The diets of farm-raised fish are often supplemented with the goal of matching the nutrient density and omega-3 levels of wild-caught fish. In the case of wild versus farmed salmon, research in The American Journal of Clinical Nutrition stated that farmed salmon contain around two times fewer omega-3s, even though it contains more fat than wild salmon. Wild salmon has been shown to have a healthier ratio of Omega-6s to Omega-3a. This is likely due to dietary differences. Farmed fish, including salmon, are often fed a diet that's supplemented with corn and soy to decrease costs. Conversely, there have been studies showing farmed fish can match the nutrient density of their wild counterparts, but it's hard to know what you're getting. In the case of salmon, there is also concern related to the "color added" phase on the farm-raised fish tag. What does it mean? Wild fish get their reddish/pink color from astaxanthin, a cartenoid with impressive antioxidant properties. Astaxanthin is produced by plants and algae and consumed by salmon through its natural diet, which often includes aquatic plants, shrimp and krill. A farm-raised fish's diet is supplemented with Aatazanthin, usually synthetic, for color as without supplementation it would be an undesirable murky, gray color. Take home tip: Wild caught fish are naturally more nutrient dense than farm-raised fish.

[Read: 11 Best Fish: High in Omega-3s -- and Environment-Friendly .]

Should you worry about toxins? Many scientist feel the benefits of eating fish outweighs the associated health risks, but it's better to understand the concerns. There are certain toxins, like PCBs (polychlorinated biphenyls), methylmercury, and others that are present in all fish, and there are ways you can minimize the amounts you consume. The United States Environmental Protection Agency has resources available on mercury levels in fish which, in short, recommend avoiding shark, swordfish, tilefish and king mackerel, as they have higher mercury levels. Shrimp, canned light tuna (as opposed to albacore, which is higher in mercury), salmon, pollock and catfish are among the common, low-mercury species that are safe for regular consumption. Environmental pollutants can occur in the wild, though they're more prevalent in fish farms considering the high amounts of fish waste, close quarters, antibiotic use and varying types of fish feed -- all which can add to toxin levels. Choose wild-caught fish harvested from clean waters or farmed fish that are grown in a clean environment, fed a clean diet and not treated with antibiotics. Cleanfish is a food resource for finding fish farms that are using improved practices.

In conclusion, though there are pros and cons associated with both farmed and wild fish, the many benefits of including fish in your diet remain true.

[Read: How to Choose a Fish Oil Supplement .]