Gaining as little as 6.5lbs above your natural weight over the course of seven years could wreak havoc on your heart, a new study claims.
Researchers at the University of Texas Southwestern tracked data on 1,262 adults for seven years, analyzing their body fat and their heart health.
To their surprise, the results were not markedly affected by how much a person weighed at the beginning of the study – overweight, underweight or normal weight.
However, fluctuations in weight, even in those who were fit and healthy, had a dramatic impact on heart muscle strength.
The research comes a day after a Harvard study warned that modest weight gains in your 20s, 30s and 40s can drastically increase one’s risk of chronic heart disease.
‘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,’ said Dr Ian Neeland, a cardiologist and assistant professor of medicine.
‘Counseling to maintain weight stability, even in the absence of weight loss, may be an important preventive strategy among high-risk individuals.’
In the study, published on Wednesday by the journal of the American Heart Association, the average age of participants was 44 years old.
Women narrowly made up the majority (57 percent). Forty-four percent of the group was black, the rest white, and 36 percent was obese. All were free from heart disease and other conditions that put them at high risk for heart disease.
At the start, each participants had an MRI scan of their heart, and underwent multiple body fat measurements.
This was repeated seven years later.
Contrasting their data, the researchers found that those who gained even as little as 5 percent of weight were more likely to have thickening and enlargement of the left ventricle, which is a key hallmark of future heart failure.
That 5 percent would be equivalent to an extra 6.5lbs in a healthy 130lb woman, or 7.5lbs in a healthy 150lb man.
They also found that people who gained modest amounts of weight over time were more likely to exhibit subtle decreases in their hearts’ pumping ability. And it wasn’t a mild thickening of the heart either.
The researchers warned that even after adjusting for factors like high blood pressure, diabetes, smoking and alcohol use, these people’s hearts looked bad.
Conversely, people who lost weight were more likely to exhibit decreases in heart muscle thickness.
The researchers said there were some limitations to their study: it was relatively small and their findings do not mean that every person with weight gain will necessarily develop heart failure.
However, the results do suggest that changes in weight may affect heart muscle in ways that can change the organ’s function.