A new study published in the journal Aging Cell has provided new insights into how calorie restriction affects telomere length and biological aging in humans.
The phase 2 trial featured non-obese men and women ages 21 to 50 years old. Participants were randomly assigned to either a 25% calorie restriction diet or were free to eat whatever they wanted for two years. A prior analysis of the study determined that 25% calorie restriction appeared to slow biological aging. This study sought to further determine whether the telomere length of participants was changed based on calorie restriction. Telomeres are parts of cells that are lost every time the cells replicate. Cells with longer telomere lengths are functionally younger than cells with shorter telomere lengths, and telomere length is one measure of biological aging. The telomere lengths of the participants in the study were measured at one year and two years to see how their diets might affect telomere length.
The results showed that people in the calorie restriction group lost telomeres at a different rate than people in the control group, but the telomere lengths of both groups were roughly the same at the end of the study.
The authors noted that factors such as stress, genetics, diet, and illnesses can affect telomere length in addition to normal aging. In this study, participants who were in the calorie restriction group lost weight and telomeres at a faster rate than the control group during the first year of the study. However, during the second year of the study, the calorie restriction group’s weight tended to stabilize, and they lost telomeres at a slower rate than the control group. These data suggest that over the long term, the calorie restriction group may have continued to lose telomeres at a lower rate. Biological aging has an important impact on many areas of health, including heart health, and finding ways to slow biological aging has potential to improve heart health over the long term.
Sources: Aging Cell, Science Daily
