Eating salmon, no matter which kind you buy, is a great way to get omega-3 fatty acids and help maintain a diet that supports your brain health. However, the method used to catch salmon makes a big difference in its nutritional value — and its price. Wild-caught salmon (typically more expensive than farm-raised) is caught in natural environments and allowed to eat organisms found naturally in these environments. Farm-raised salmon, on the other hand, live in pens or tanks that operate with varying levels of sustainability and are fed processed, high-fat, high-protein pellets. As a result, farmed salmon typically contains more fat, including both unsaturated and saturated fat, in the same number of grams of fish and contains fewer nutrients such as calcium and zinc, according to data from the USDA. While the larger amount of unsaturated fat may actually be a good thing, some consumers avoid farm-raised salmon due to the increased risk of contaminants such as polychlorinated biphenyls (PCBs), antibiotics and mercury.