Gaining weight – even a small amount – may alter the structure and function of heart muscle, according to a new study published in the Journal of the American Heart Association.
The results suggest that changes in weight may affect heart muscle in ways that can change the organ’s function.
The researchers, from the University of Texas, followed 1,262 adults for seven years. At the beginning of the study they were all free from heart disease. Participants had MRIs scans of their hearts and multiple body fat measurements at the start of the study and then again seven years later.
They found that those who gained weight, even as little as 5 per cent, were more likely to have thickening and enlargement of the left ventricle, which is a well-established indicators of future heart failure.
They were also more likely to exhibit subtle decreases in their hearts’ pumping ability; and were more likely to exhibit changes in heart muscle appearance and function that persisted even after the researchers eliminated other factors that could affect heart muscle performance and appearance, including high blood pressure, diabetes, smoking and alcohol use.
Conversely, people who lost weight were more likely to exhibit decreases in heart muscle thickness.
The amount a person weighed at the beginning of the study didn’t impact the changes, suggesting that even those of normal weight could experience adverse heart effects if they gain weight over time, the researchers said.
The study’s senior author, Ian Neeland, said: ‘Any weight gain may lead to detrimental changes in the heart above and beyond the effects of baseline weight so that prevention should focus on weight loss or if meaningful weight loss cannot be achieved – the focus should be on weight stability.’
‘Counselling to maintain weight stability, even in the absence of weight loss, may be an important preventive strategy among high-risk individuals.’
This study essentially supports the idea that gaining weight, even in small amounts, can lead to increased risk of heart failure. Possibly the biggest drawback of a study like this is that, although some confounding variables were accounted for, there are likely to have been other factors that could influence the outcome (like dietary habits) which could not have been accounted for.
However, the take home message still seems to be a sensible one – that high risk individuals can still potentially help themselves by not putting on more weight, even if they find it difficult to lose weight.