Climate change may halve omega‑3 fatty acids in fish and the organisms they eat

This article has been reviewed according to Science X's editorial process and policies. Editors have highlighted the following attributes while ensuring the content's credibility: You've probably heard that eating fish and other seafood is good for your health. One of the main reasons is that seafood is an excellent source of two important omega-3 fats called and DHA. and DHA are critical for the development and function of the brain, eyes and heart.

They also reduce chronic inflammation, which is linked to many chronic diseases. They can also reduce the risk of premature births and perhaps even some types of cancer. While humans can produce and DHA from ALA (an omega-3 fat found in plants), and it's possible to get them from foods such as flaxseed and walnuts, seafood is the main source for most people.

However, our new study shows that many fish and other seafood will contain fewer omega-3s over time because of rising ocean temperatures as the climate changes. In fact, we found omega-3 levels could drop by 50% under very high-warming scenarios. This is very bad news for human health, but also for the health of other animals in the food web.

Marine algae are among the only forms of life that produce and DHA omega-3s. Examples of marine algae include seaweeds and diatoms (a type of phytoplankton). Marine algae form the base of marine food webs—a term that means the feeding relationships of different species within an ecosystem.

This means marine algae are crucial sources of micronutrients to all animals. When animals, such as invertebrates like crabs and starfish, eat marine algae, they obtain and DHA. This is passed up the food chain as fish or other larger animals eat those invertebrates.

Eventually, and DHA reach humans through the seafood we eat. However, if and DHA levels are disrupted along the food chain, fewer of those crucial fatty acids are available for animals higher up—including humans. Our systematic review aimed to understand how climate change may affect these essential fats.