Sept. 12 (UPI) -- New research suggests the availability of omega-3, the brain-building fatty acid, could be significantly diminished by global warming.
The omega-3 fatty acid called docosahexaenoic acid, or DHA, is the most abundant fatty acid in mammalian brains. It plays a vital role in neural development and health, protecting cells and reducing inflammation.
But humans don't produce enough DHA on their own. Instead, they rely on fish and seafood to boost DHA levels. Previously, some scientists have hypothesized that our earliest human ancestors were able to boost brain development by taking advantage of marine food sources and gaining access to greater levels of fatty acids.
DHA is mostly produced by algae. It accumulates as it works its way up the aquatic food chain.
The biochemical reactions involved in the fatty acid's production are sensitive to changes in temperatures. To determine how global warming might affect the availability of DHA, scientists ran a variety simulations.
The models -- described this week in the journal Ambio -- showed rising global temperatures and growing human populations will leave 96 percent of humans without access to sufficient amounts of DHA.
In places like Scandinavia, with relatively small populations and access to DHA-rich fish, the fatty acid's availability won't be a problem. But in Asia and Africa, where populations are growing and DHA is harder to come by, the vast majority of people will struggle to consume the recommended daily DHA dose of 100 milligrams per day.
"According to our model, global warming could result in a 10 to 58 percent loss of globally-available DHA in the next 80 years," Stefanie Colombo, researcher at Dalhousie University in Canada, said in a news release. "A decrease in levels will have the greatest effect on vulnerable populations and periods of human development, such as fetuses and infants, and may also affect predatory mammals, especially those in polar regions."
Researchers populated their models with data from the Sea Around Us initiative, which collects data related to the effects of fishing on the health of marine ecosystems. Scientists also relied on data compiled by United Nations researchers for global inland fisheries catch and aquaculture production data.
Scientists used the data to build a mathematical model that predicted how rising temperatures would alter the availability of DNA in marine and freshwater food chains.
"It is also interesting to see that freshwater fishing zones showed greater declines in DHA than marine zones, due to larger projected temperature increases in freshwater than the oceans," Colombo said. "Changes in availability of DHA may therefore have a greater impact on populations in certain areas of the world, especially inland Africa."