Excess weight could lead to heart failure in time, according to new research.
Heart failure takes place when the heart muscle becomes abnormally weak, leaving it unable to pump enough blood to supply a sufficient amount of oxygen to the body.
According to the National Heart, Lung, and Blood Institute (NHLBI), approximately 5.7 million people in the United States are affected by heart failure. The NHLBI also state that overweight people are at a severe risk of heart failure; excess weight puts too much pressure on the heart muscle.
A new study - undertaken by Dr. Ian Neeland, from the University of Texas Southwestern Medical Center in Dallas, and colleagues - shows that gaining even a small amount of weight will impact the health of the heart muscle over time. Their findings were published in the Journal of the American Heart Association.
Weight gain increases risk
The study comprised 1,262 participants with an average age of 44. Fifty-seven percent of these were women, 44 percent of them were black, and 36 percent were obese. The percentages are representative of the populations most at risk of developing heart failure or heart disease, according to the NHLBI and Harvard Medical School in Boston, MA.
At the beginning of the study, none of the participants had experienced heart failure or other conditions that placed them at an increased risk of heart failure. Their heart health status was monitored for a period of 7 years.
MRI scans of the participants' hearts, as well as their body fat measurements, were taken both at baseline and at the end of the study.
It was found that the participants who had gained weight during the follow-up period were more likely to also experience negative effects on the heart muscle.
The thickening and enlargement of the left heart ventricle - a tell-tale sign of heart failure - was more likely to occur in participants who had put on even moderate weight. As little as a 5 percent weight gain could be detrimental.
These participants were also likelier to have a weaker heart - that is, it may experience some degree of difficulty in pumping blood through the body.
More importantly, in the case of those who had gained weight, the alterations in the appearance and function of the heart muscle persisted after the exclusion of other factors relevant to heart health conditions, such as hypertension, diabetes, smoking, and alcohol consumption.
Maintaining normal weight counteracts risk
In contrast, it was found that the participants who had lost weight during the 7-year follow-up period were likelier to have a thinner heart muscle.
The researchers also noted that the participants' weight at the beginning of the study had no impact on the final results.
But there is an intuitive fix to the risks posed by weight gain to the heart: maintaining weight can help to sustain the health of the heart muscle.
"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."
Dr. Ian Neeland
Dr. Neeland and colleagues also acknowledge some limitations of the study, mentioning the small size of the population sample and specifying that not all the individuals who put on weight will be subject to the risk of heart failure.
The researchers add that their findings would benefit from further investigation focusing on some benefits and disadvantages of using more aggressive weight management to neutralize the effects of excess weight on the heart.