For years, cholesterol and saturated fats have been the "bad actors" linked to diabetes in humans, but recent research with dolphins suggest there's one saturated fat that could prevent the disease in people, researchers say.
Scientists at the National Marine Mammal Foundation say they've discovered dolphins can easily fall into a diabetes-like state, and can even develop a condition known as metabolic syndrome, which, in humans is also called prediabetes.
"To better understand what may be a driver for metabolic syndrome in dolphins, we started exploring their diet, which is primarily fish," says Stephanie Venn-Watson, head of the foundation's Translational Medicine and Research Program.
Writing in the journal PLOS ONE, the researchers report they found that heptadecanoic acid, a saturated fat found in fish that's also present in many fat-filled dairy products, had a beneficial effect on the metabolism of dolphins.
"Dolphins with higher levels of heptadecanoic acid in their blood had lower insulin and triglycerides," says Venn-Watson, the study leader.
To help confirm the suspected link between the acid and metabolic benefits, the researchers selected a group of dolphins displaying low levels of heptadecanoic acid and put them on a diet of fish that are high in the fatty acid.
In six months, elevated levels of glucose, insulin and triglycerides — signs of metabolic syndrome — in the dolphins returned to normal, they reported.
The saturated fat heptadecanoic acid, also known as margaric acid, is present in dairy products, rye and various types of fish. The highest levels in dairy products are normally found in whole fat milk, full fat yogurt and particularly in butter, the researchers note.
The researchers say they're working with children's hospitals to see if low levels of heptadeconoic acid are present in children diagnosed with metabolic syndrome and diabetes.
Changing trends in human diets may be a factor in the modern prevalence of diabetes, Venn-Watson suggests.
"We hypothesize that widespread movement away from whole fat dairy products in human populations may have created unanticipated heptadecanoic acid deficiencies," she says, "and, in turn, this dietary deficiency may be playing a role in the global diabetes pandemic."
More than 85 million Americans — one out of every three adults — have metabolic syndrome, according to estimates from the Centers for Disease Control and Prevention.
Thinking of eating like a dolphin or maybe adding huge amounts of butter to your daily diet? Take a moment, says Venn-Watson.
"Butter may have both good and bad saturated fats, but it's always best to check with your physician before making changes to your diet," she says.