Fatty fish, like wild-caught salmon, is a natural source of long-chain omega-3 fatty acids, a type of fat associated with certain health benefits. Although certain plant-based foods, like flaxseed, chia seeds, and walnuts, contain short-chain omega-3s, it’s not clear whether short-chain omega-3s carry the same benefits as the long-chain form.
Your body can convert short-chain omega-3s to long-chain but it doesn’t do so efficiently. In fact, less than 5% of the plant-based, short-chain omega-3s you take in actually gets converted. Not a fish lover? Rather than eat fatty fish, some people opt to take fish oil capsules. Fish oil capsules contain a concentrated form of long-chain omega-3s, but getting omega-3s this way may not be reliable. Here’s why.
Why Do You Need Long-Chain Omega-3s Anyway?
Long-chain omega-3s are an important component of cell membranes and are present in high concentrations in the brain. Research also suggests omega-3s have anti-inflammatory properties and help counteract the pro-inflammatory effects of omega-6 fatty acids. These are the fats most people get too much of. The traditional American diet contains a high ratio of omega-6s to omega-3s, as high as 16 to 1, when a healthier ratio would be closer to 2 or 3 to 1. Processed foods are loaded with omega-6s!
Although studies are somewhat conflicting, research shows long-chain omega-3s may benefit brain health. In fact, some studies suggest they slow cognitive decline and are helpful for treating anxiety and depression symptoms. Other research shows they lower the incidence of stroke by reducing the risk of clot formation.
In terms of heart health, they raise HDL-cholesterol, the more favorable type, and lower triglycerides, although research showing they prevent heart disease or heart attacks is inconsistent. Because of their anti-inflammatory properties, they may also help ease pain and stiffness for people with arthritic conditions. Plus, there’s some evidence that omega-3s lower the risk of breast cancer, although it’s less clear whether it’s protective against other forms of cancer.
Here’s the kicker. Most research that shows long-chain omega-3s have health benefits are studies where people consumed fatty fish, not fish oil capsules. As a number of nutritional studies show, taking a supplement doesn’t always have the same benefits as eating the actual food – but that’s not the only reason to cast a critical eye on fish oil capsules.
The Dark Side of Fish Oil Capsules
In one study, researchers tested 32 fish oil supplements derived from fatty fish. The supplements were carefully stored in a dark place prior to testing. They analyzed the specimens for the quantity of long-chain omega-3s and the ratio of oxidized omega-3 fatty acids. Omega-3s are relatively unstable and can form oxidation products if exposed to light or heat.
Why are oxidized omega-3s a problem? For one, they lack the health benefits of non-oxidized ones. Secondly, oxidized omega-3s could harm cells and tissues although it’s not clear whether this actually happens. At the very least, when a fish oil supplement is oxidized or rancid, the oxidized omega-3s aren’t active.
So, what did the study show? More than 90% of the samples they tested, from a variety of manufacturers, contained less omega-3s than what was stated. Even worse, almost half of the supplements were oxidized or “spoiled.” One problem with fish oil capsules is you can’t tell if the product is spoiled or rancid since it’s enclosed in a capsule. You can’t smell the characteristic unpleasant aroma that suggests it’s oxidized.
What did the researchers conclude? The reason most fish oil supplements contain less long-chain omega-3s than stated is because some of the fatty acids were already oxidized and rancid. When fish oil is enclosed in a capsule, you have no way of knowing how much of the omega-3s are already oxidized, whereas you KNOW when fish is rancid by its smell. Combine that with the fact that most studies show dietary fish rather than supplements are where the benefits lie.
The Benefits of Eating Fish Over Taking a Supplement
Almost all fish are relatively low in calories and an excellent source of protein. When you eat fish, you’re not consuming an isolated component but getting the benefits of “synergy,” the interplay of chemicals and compounds that work together to promote health.
If you’re trying to build lean body mass, getting more long-chain omega-3s may work in your favor. Research shows long-chain omega-3s turn on anabolic pathways that boost muscle protein synthesis. Plus, they block the effects of cortisol, a hormone that stimulates muscle breakdown in response to stress. Studies also show omega-3s may help older people preserve lean body mass with age. Combine fatty fish with resistance training and you have a powerful combo!
The Bottom Line
Get your long-chain omega-3s by eating fatty fish. Wild-caught salmon is a good choice but avoid farm-raised fish. Farm-raised salmon contains lower levels of omega-3s and may have higher levels of toxins. Other fish that are high in long-chain omega-3s include anchovies, sardines, tuna, mackerel, herring, white fish, and black cod. Keep in mind that larger fish generally accumulate higher levels of toxins and heavy metals than smaller fish. That’s why sardines are a good choice. All in all, you can get your long-chain omega-3s by eating a generous serving of wild-caught salmon twice a week.
If you take a fish oil capsules, buy it from a reputable manufacturer and refrigerate it as soon as it arrives. This will slow the rate of oxidation. Don’t buy those super-size bottles either. The longer you have them, the more opportunity there is for them to oxidize. If you want to be sure the fish oil capsules you have is still viable, open a capsule and smell or taste it. If it has a disagreeable odor or a rancid taste, toss it.
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