Research with dolphins provides hope for prevention of diabetes in humans

July 22, 2015, National Marine Mammal Foundation

For decades, the public has been told to avoid foods high in saturated fats and cholesterol. A new study led by the National Marine Mammal Foundation (NMMF) and published in PLOS ONE today discovered a saturated fat, called heptadecanoic acid, that may help reverse prediabetes in humans.

NMMF research discovered that bottlenose dolphins can readily switch in and out of diabetes-like states, and that dolphins - including those in the wild - can develop metabolic syndrome, a subclinical condition called prediabetes in humans. "To better understand what may be a driver for metabolic syndrome in dolphins, we started exploring their diet, which is primarily fish," said Dr. Stephanie Venn-Watson, Director of NMMF's Translational Medicine and Research Program and the study's lead author.

Because of the popularity of fish-based as a human health supplement, NMMF's team started by assessing fatty acid blood levels in 49 dolphins, as well as in their dietary fish. "We were surprised to find that among the 55 fatty acids studied, the heptadecanoic acid appeared to have had the most beneficial impact on dolphin metabolism," said Venn-Watson. "Dolphins with higher levels of heptadecanoic acid in their blood had lower insulin and triglycerides." The study also showed that while some fish have high levels of heptadecanoic acid, other fish types had none.

Six dolphins with low heptadecanoic acid were then fed fish high in this fatty acid. Within six months on the new diet, indicators of metabolic syndrome in dolphins, including elevated insulin, glucose, and triglycerides normalized. Key to this surprising outcome was reversal of high ferritin, an underlying precursor to metabolic syndrome. "We saw blood ferritin levels decrease in all six dolphins within three weeks on the new diet," said Venn-Watson.

Heptadecanoic acid, also called margaric acid or C17:0, is a saturated fat found in dairy fat, rye, and some fish. The NMMF study showed no detectable heptadecanoic acid in nonfat dairy product and some amount in low fat dairy products. The highest levels were found in whole fat milk, yogurt, and especially butter. The fish with the highest heptadecanoic acid content was mullet.

"We hypothesize that widespread movement away from whole fat dairy products in human populations may have created unanticipated heptadecanoic acid deficiencies," said Venn-Watson, "and, in turn, this dietary deficiency may be playing a role in the global diabetes pandemic." Today, the Centers for Disease Control and Prevention estimates that over 86 million people in the U.S. have metabolic syndrome—tone in every three adults.

"This study is a good example of how improving dolphin health can have an added benefit to human health, too," said NMMF President Dr. Sam Ridgway.

NMMF is partnering with children's hospitals to see if children with and diabetes also have low heptadecanoic levels. The NMMF is also studying how changes in ocean prey due to climate change and other environmental impacts are affecting metabolism of wild .

NMMF's discovery aligns well with growing scientific evidence demonstrating that cholesterol and some fats may not be as bad as once thought. Earlier this year, the American Dietary Guidelines changed its recommendations related to , including removing the need for most people to limit their dietary cholesterol intake (high cholesterol comes primarily from what our body produces, not what we eat).

Does this mean that we can now eat butter without guilt? Dr. Venn-Watson says, "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."

Explore further: Is coconut oil good for you?

More information: PLOS ONE Published: July 22, 2015. DOI: 10.1371/journal.pone.0132117

Related Stories

Is coconut oil good for you?

September 29, 2014
There is no consistent body of data that I am aware of to indicate that coconut oil has documented specific beneficial effects; hence, there is no data that I'm aware of to suggest people should go out of their way to consume ...

Doubling saturated fat in the diet does not increase saturated fat in blood, study finds

November 21, 2014
Doubling or even nearly tripling saturated fat in the diet does not drive up total levels of saturated fat in the blood, according to a controlled diet study.

Fatty acid composition in blood reflects the quality of dietary fat and carbohydrates in children

April 7, 2014
Recently published research in the University of Eastern Finland found that fatty acid composition in blood is not only a biomarker for the quality of dietary fat but also reflects the quality of dietary carbohydrates. For ...

High-fat dairy products linked to reduced type 2 diabetes risk

April 2, 2015
Consumption of high-fat yoghurt and cheese are linked to a reduction in the risk of type 2 diabetes by as much as a fifth, according to new research from Lund University in Sweden. High meat consumption, on the other hand, ...

Intake of the right fatty acids can help to prevent heart attacks

June 30, 2011
There is much confusion at present about the importance of fatty acids in preventing heart attacks. Recent studies have questioned the need to reduce the intake of saturated fatty acids in the diet and to increase that of ...

Soybean oil causes more obesity than coconut oil and fructose

July 22, 2015
A diet high in soybean oil causes more obesity and diabetes than a diet high in fructose, a sugar commonly found in soda and processed foods, according to a just published paper by scientists at the University of California, ...

Recommended for you

US paves way to get 'lab meat' on plates

November 17, 2018
US authorities on Friday agreed on how to regulate food products cultured from animal cells—paving the way to get so-called "lab meat" on American plates.

Youth dating violence shaped by parents' conflict-handling views, study finds

November 16, 2018
Parents who talk to their children about nonviolent ways of resolving conflict may reduce children's likelihood of physically or psychologically abusing their dating partners later—even when parents give contradictory messages ...

A low-gluten, high-fiber diet may be healthier than gluten-free

November 16, 2018
When healthy people eat a low-gluten and fibre-rich diet compared with a high-gluten diet, they experience less intestinal discomfort including less bloating. Researchers at University of Copenhagen show that this is due ...

Why we shouldn't like coffee, but we do

November 15, 2018
Why do we like the bitter taste of coffee? Bitterness evolved as a natural warning system to protect the body from harmful substances. By evolutionary logic, we should want to spit it out.

Dietary fat is good? Dietary fat is bad? Coming to consensus

November 15, 2018
Which is better, a low-fat/high-carbohydrate diet or a high-fat/low-carbohydrate diet—or is it the type of fat that matters? In a new paper featured on the cover of Science magazine's special issue on nutrition, researchers ...

Survey reveals how we use music as a possible sleep aid

November 14, 2018
Many individuals use music in the hope that it fights sleep difficulties, according to a study published November 14 in the open-access journal PLOS ONE by Tabitha Trahan of the University of Sheffield, UK, and colleagues. ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.