The Mediterranean diet may protect against diabetes more than realized, science shows

The Mediterranean diet has already been shown to help protect the aging brain and may significantly reduce the risk of heart disease. A new study has now found a much stronger link than previously found between the Mediterranean diet – filled with whole grains, fish, fruit and olive oil – and a reduced risk of Type 2 diabetes.

Previous research on the impact of the Mediterranean diet on diabetes has shown mixed results, perhaps because the studies were based on participants remembering and self-reporting the type of food they ate.

For the new research, published Thursday in PLOS Medicine, British scientists used blood samples to develop a biomarker scoring system. They first ran a small trial, called the Medley trial, with 128 adults aged 65 and over who were randomized to either eat a Mediterranean diet or continue eating as they normally did for six month.

A comparison of blood samples from the two groups resulted in a number of biomarkers for fatty acids and carotenoids, the substances that give color to vegetables such as pumpkins, carrots and tomatoes.

For the second part of the research, scientists from the University of Cambridge, in the United Kingdom, analyzed data – including blood samples and self-reported dietary information – from more than 340,000 middle-aged participants in a long-term European study. Over about 10 years, 9,453 developed Type 2 diabetes.

The researchers then compared biomarker scores from the 9,453 to 12,749 randomly selected participants without diabetes in the large study.

They found a nearly 30% reduction in diabetes risk using the biomarker data, compared to a 10% reduction from the self-reported data. This means that previous studies have probably underestimated the impact of the Mediterranean diet.

The findings strengthen the case for recommending the Mediterranean diet to prevent Type 2 diabetes, said senior author Dr. Nita Forouhi, professor of population health and nutrition and program leader in nutritional epidemiology at the University of Cambridge.

“The 20% of participants with the highest biomarker score values ​​had a 62% lower risk of new-onset type 2 diabetes compared to the 20% with the lowest biomarker score values,” Forouhi said in an email.

What is a Mediterranean diet?

For a person consuming an average of 2,000 calories per day, researchers defined it as, at least:

  • 2 to 3 tablespoons of olive oil.
  • Five servings of vegetables (75 g each).
  • Two or three servings of fruit (150 g each).
  • Five servings of cereal products (between 30-120 g each depending on the specific product).

And a daily maximum of:

  • One medium potato.
  • One serving of milk (250 ml).
  • Two glasses of red wine (150 ml each).

Weekly recommendations included:

  • Six servings of low-fat Greek yogurt (170 g each).
  • One to three servings of poultry (100 g each).
  • At least five servings of nuts (35 g each).
  • At least three servings of legumes (75 g each).
  • At least three servings of fish (150 g each).

And a maximum of:

  • Four servings of cheese (40 g each).
  • One serving of red meat (100 g).
  • Five eggs.

Dr. Peter Goulden, chief of the division of endocrinology, diabetes and bone diseases at Mount Sinai Morningside and Mount Sinai West, called the new biomarker an exciting development.

“If you compare the biomarker score to the self-reports, the effect is three times greater,” said Goulden, who is also an associate professor at the Icahn School of Medicine at Mount Sinai. “So that’s very powerful.”

Further studies will be needed to confirm the findings and determine whether they would apply to a wider population, he said.

An advantage is that the biomarkers do not determine whether the benefits are from fruit and vegetable consumption or some other aspect of the diet, said Linda Van Horn, a clinical nutrition epidemiologist at the Feinberg School of Medicine, Northwestern University in Chicago.

Still, this approach is “more objective, so I’d say it’s a step in the right direction,” she said.

The importance of the results is emphasized by the rising rates of diabetes worldwide, said Dr. Anna Beth Bradley, assistant professor of medicine, diabetes, endocrinology and metabolism at Vanderbilt University School of Medicine.

“If you look at the prevalence of diabetes around the world, you see that the incidence in Europe is about 6% to 7%, and in the US, it’s about 11%, which suggests that the normal -American diet with the rise. in diabetes,” said Bradley. “That terrible American diet is leaking over to other countries with diabetes rising in almost every country.”

Leave a Reply

Your email address will not be published. Required fields are marked *