Mediterranean diet sparks transition to healthier obesity phenotypes
Strict adherence to a Mediterranean diet showed potential for improving metabolic health and protecting against progression to obesity for adults, according to findings published in Clinical Nutrition.
“Metabolic and body size phenotyping might be crucial to identify at-risk subjects and to optimize prevention and treatment strategies. Until now, prevalence, nature, determinants and clinical implications of obesity phenotypes [have] been mainly studied, but the effect of lifestyle targeting transition from one to other phenotype has received less attention,” Dora Romaguera, PhD, of the Instituto de Investigación Sanitaria Illes Balears (IdISBa), University Hospital Son Espases in Palma de Mallorca, Spain, and colleagues wrote. “The [Mediterranean diet] has been proposed as a promising lifestyle factor to allow the transition to healthier obesity phenotypes and reduction of long-term health risk.”
Romaguera and colleagues examined 5-year follow-up data from 5,801 adults (58% women) aged 55 to 80 years in the PREDIMED study. All participants were free of cardiovascular disease at the onset of the study, which evaluated the Mediterranean diet in Spain from 2003 to 2010. Participants completed a questionnaire to report their adherence to the diet, with higher adherence marked by higher scores from a list of 14 binary questions. Participants were also measured for BMI and waist circumference on an annual basis.
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The researchers established four obesity phenotypes in the cohort. The first was metabolically healthy obesity, which required a BMI of 30 kg/m2 or more and two or fewer markers of metabolic syndrome. The second was metabolically abnormal obesity, which required a BMI of 30 kg/m2 and more than two markers for metabolic syndrome. Metabolically healthy non-obesity and metabolically abnormal non-obesity phenotypes matched their obesity counterparts for metabolic syndrome markers but required a BMI of less than 30 kg/m2.
Participants with metabolically healthy obesity changed phenotype at the highest rate (43%), primarily shifting to metabolically abnormal obesity, whereas 85% of those with metabolically abnormal obesity did not change their status. More than 70% of participants in both groups without obesity maintained that status.
For those who transitioned to another phenotype, the researchers found that there was a 16% increase (95% CI, 3-31) in the odds of going from having metabolically abnormal obesity to having metabolically healthy obesity when Mediterranean diet adherence was increased by 2 points. In addition, the researchers found an association between a 2-point increase in diet adherence and a 14% reduction in risk for deteriorating metabolic health (95% CI, 3-23) for participants with metabolically healthy obesity.
The risk for a transition from metabolically healthy non-obesity to metabolically healthy obesity was lowered by 18% (95% CI, 5-30) with a 2-point improvement in diet adherence, although the researchers noted that this occurred at a significant level only in women. Similarly, the researchers observed that a 2-point increase in diet adherence was related to a 12% increase (95% CI, 1-23) in the odds of transitioning from metabolically abnormal non-obesity to metabolically healthy non-obesity but only in women.
“This study supports the relevance of the combined metabolic and body size phenotyping to improve early detection of subgroups at higher health risk. Moreover, our findings suggest that promotion of the [Mediterranean diet] is a dietary strategy for preventing or treatment of obesity or [metabolic syndrome],” the researchers wrote. “These results add to the bulk of literature showing that the [Mediterranean diet] is a sustainable and effective dietary pattern for the promotion of overall health, as reflected by the inclusion of this dietary pattern in relevant dietary guidelines worldwide.” – by Phil Neuffer
Disclosures: Romaguera reports no relevant financial disclosures. Please see the study for all other authors’ relevant financial disclosures.