Male Offspring in Long-Lived Families are Less Fat

The amount of visceral fat carried by individuals, just like number of calories consumed, has a strong influence on natural variations in health and longevity. More visceral fat is a bad thing, producing chronic inflammation and other less well understood disruptions of metabolism. This study shows that men, but not women, in long-lived families are less fat. That this is the case for only one gender is some defense against the hypothesis that the important factor being passed down here is culture (choosing to eat less) rather than genes, which would put a damper on many claims of genetic associations in longevity.

If the case, this would be an analogous situation to many life span studies in mice in recent decades that failed to control for inadvertent calorie restriction, and thus mistakenly identified various interventions as being life-extending, when in fact it was simply a matter of reduced calorie intake. The consequences of differences in visceral fat tissue, like those of dietary calorie intake, are large in comparison to most other influences on long term health at the present time, and so caution should be the watchword. Read studies carefully.

Familial longevity is marked by an exceptionally healthy metabolic profile and low prevalence of cardiometabolic disease observed already at middle age. We aim to investigate whether regional body fat distribution, which has previously shown to be associated with cardiometabolic risk, is different in offspring of long-lived siblings compared with controls.

Our institutional review board approved the study, and all participants (n = 344, average age in years 65.6) gave written informed consent. Offspring (n = 175) of nonagenarian siblings were included. Their partners (n = 169) were enrolled as controls. For abdominal visceral adipose tissue (VAT) and subcutaneous adipose tissue (SAT) measurements, a single-slice 8.0 mm computed tomography (CT) acquisition was planned at the level of the 5th lumbar vertebra. In addition, participants underwent prospectively electrocardiography-triggered unenhanced volumetric CT of the heart. Abdominal VAT and SAT areas and epicardial adipose tissue (EAT) volumes were acquired. Linear regression analysis was performed adjusting for cardiovascular risk factors.

Total abdominal fat areas were smaller in male offspring compared with controls (353.0 versus 382.9 cm2). The association between low abdominal VAT areas in male offspring (149.7 versus 167.0 cm2 in controls) attenuated after additional adjustment for diabetes. Differences were not observed for females. EAT volumes were similar between offspring of long-lived siblings and controls. We conclude that males who have genetically determined prospect to become long-lived have less abdominal fat and in particular less abdominal VAT compared with controls.

Link: http://dx.doi.org/10.1093/ageing/afv063