Final answer:
Fish oil supplements like those available at Wal-Mart may vary in their concentration of omega-3 fatty acids, including DHA. The added benefit of these supplements can be minimal if one's diet already includes sufficient omega-3 because of seafood consumption. The specific recommendation for fish oil supplements may depend on individual dietary needs and potential cardiovascular risk factors.
Step-by-step explanation:
The fish oil that you can buy at places like Wal-Mart may differ from other fish oil supplements in terms of its concentration of omega-3 fatty acids, such as Docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA). While DHA and EPA are important omega-3 fatty acids that are associated with various health benefits including potentially lowering the risk of cardiovascular disease, aiding rheumatoid arthritis, and improving infant brain development, not all supplements are of the same quality or potency. It's also important to note that if you are already consuming sufficient omega-3s through your diet, particularly by meeting the Dietary Guidelines for Americans which recommend eating 8 ounces of seafood each week, the additional benefits from taking a fish oil supplement may be minimal.
The inconsistent results from studies may also be attributed to the fact that not all research measures the participants' existing omega-3 levels or their dietary intake prior to the supplementation. Moreover, for individuals at risk of cardiovascular disease who don't regularly consume fish, some doctors might recommend an omega-3 or fish oil supplement as part of their dietary plan.