New Study Reveals Why We Gain Weight As We Age
A new study published in Nature Medicine has revealed important insights into the aging process.
It?s common knowledge that as we age and our metabolism slows down, our muscle tissue starts to weaken and we start to gain weight. But although this is easily observed in the world around us, many of the biological mechanisms that underly aging and weight gain are still misunderstood. A recent Swedish study into aging and weight gain has determined that decreasing lipid turnover in fatty tissue is a leading cause of weight gain as we age.
What does lipid turnover mean?
In biology, turnover is the rate at which our body consumes and replaces different types of proteins. Different proteins have different rates at which they are consumed. Lipids are a group of naturally occurring organic compounds in the body which include fats and oils.
The study, which tracked 65 people over a 13 year period, showed that lipid turnover decreased in every subject regardless of whether they gained or lost weight. In simple terms, it means that the process of their bodies consuming and replacing fats ? as opposed to just storing them ? slowed down over that period for every individual. The study is also notable because it proved that aging, independent of other factors such as diet and exercise, is the primary agent in kickstarting this process.
How does lipid turnover affect weight gain?
Slow lipid turnover has long been associated with obesity in people of all ages. Understanding how lipid turnover functions has been critical to scientists interested in the health problems associated with weight and obesity. As mentioned in the abstract of the study, it was previously unknown ?whether lipid turnover is constant over the life span or changes during weight increase or loss.? This study shows that there are factors that can change the body?s natural rate of fat consumption.
This is great news for bodybuilders, who have been arguing for awhile now about the role of metabolism in the fitness world. Although this is only one small piece of the puzzle, it does suggest that we have more control than we think over the body?s natural processes, and that the key to unlocking their secrets could be out there somewhere.
Adipose lipid turnover and long-term changes in body weight
Abstract
The worldwide obesity epidemic1 makes it important to understand how lipid turnover (the capacity to store and remove lipids) regulates adipose tissue mass. Cross-sectional studies have shown that excess body fat is associated with decreased adipose lipid removal rates2,3. Whether lipid turnover is constant over the life span or changes during long-term weight increase or loss is unknown. We determined the turnover of fat cell lipids in adults followed for up to 16 years, by measuring the incorporation of nuclear bomb test-derived 14C in adipose tissue triglycerides. Lipid removal rate decreases during aging, with a failure to reciprocally adjust the rate of lipid uptake resulting in weight gain. Substantial weight loss is not driven by changes in lipid removal but by the rate of lipid uptake in adipose tissue. Furthermore, individuals with a low baseline lipid removal rate are more likely to remain weight-stable after weight loss. Therefore, lipid turnover adaptation might be important for maintaining pronounced weight loss. Together these findings identify adipose lipid turnover as an important factor for the long-term development of overweight/obesity and weight loss maintenance in humans.
Source: https://www.nature.com/articles/s41591-019-0565-5
A new study published in Nature Medicine has revealed important insights into the aging process.
It?s common knowledge that as we age and our metabolism slows down, our muscle tissue starts to weaken and we start to gain weight. But although this is easily observed in the world around us, many of the biological mechanisms that underly aging and weight gain are still misunderstood. A recent Swedish study into aging and weight gain has determined that decreasing lipid turnover in fatty tissue is a leading cause of weight gain as we age.
What does lipid turnover mean?
In biology, turnover is the rate at which our body consumes and replaces different types of proteins. Different proteins have different rates at which they are consumed. Lipids are a group of naturally occurring organic compounds in the body which include fats and oils.
The study, which tracked 65 people over a 13 year period, showed that lipid turnover decreased in every subject regardless of whether they gained or lost weight. In simple terms, it means that the process of their bodies consuming and replacing fats ? as opposed to just storing them ? slowed down over that period for every individual. The study is also notable because it proved that aging, independent of other factors such as diet and exercise, is the primary agent in kickstarting this process.
How does lipid turnover affect weight gain?
Slow lipid turnover has long been associated with obesity in people of all ages. Understanding how lipid turnover functions has been critical to scientists interested in the health problems associated with weight and obesity. As mentioned in the abstract of the study, it was previously unknown ?whether lipid turnover is constant over the life span or changes during weight increase or loss.? This study shows that there are factors that can change the body?s natural rate of fat consumption.
This is great news for bodybuilders, who have been arguing for awhile now about the role of metabolism in the fitness world. Although this is only one small piece of the puzzle, it does suggest that we have more control than we think over the body?s natural processes, and that the key to unlocking their secrets could be out there somewhere.
Adipose lipid turnover and long-term changes in body weight
Abstract
The worldwide obesity epidemic1 makes it important to understand how lipid turnover (the capacity to store and remove lipids) regulates adipose tissue mass. Cross-sectional studies have shown that excess body fat is associated with decreased adipose lipid removal rates2,3. Whether lipid turnover is constant over the life span or changes during long-term weight increase or loss is unknown. We determined the turnover of fat cell lipids in adults followed for up to 16 years, by measuring the incorporation of nuclear bomb test-derived 14C in adipose tissue triglycerides. Lipid removal rate decreases during aging, with a failure to reciprocally adjust the rate of lipid uptake resulting in weight gain. Substantial weight loss is not driven by changes in lipid removal but by the rate of lipid uptake in adipose tissue. Furthermore, individuals with a low baseline lipid removal rate are more likely to remain weight-stable after weight loss. Therefore, lipid turnover adaptation might be important for maintaining pronounced weight loss. Together these findings identify adipose lipid turnover as an important factor for the long-term development of overweight/obesity and weight loss maintenance in humans.
Source: https://www.nature.com/articles/s41591-019-0565-5
