An international team of scientists led by the University of Leicester has uncovered evidence that links faster 'biological' aging to a higher risk of developing age-related diseases such as heart disease, multiple sclerosis and various cancers.
The study team examined a particular feature of chromosomes called telomeres. Telomeres sit on the end of chromosomes and shorten a little each time one of our cells divides to make new cells. When they reach a critical short length, our cells enter an inactive state and then die.
Telomeres shorten as we get older, but individuals are born with different telomere lengths and the rate at which they shorten can also vary. In fact, the speed with which telomeres wear down is believed to be a measure of 'biological aging'.
Although heart disease and cancers become more common as we get older, not everyone gets them - while others may even get them at an earlier age than normal. This new data suggests that the occurrence of these diseases may be related to some people ‘biologically’ aging more quickly than others.
The research team measured telomere lengths in over 48,000 individuals and identified seven genetic variants in their DNA related to telomere length. They further found that these variants were linked to a higher than average risk of several types of cancers including colorectal cancer as well as multiple sclerosis and celiac disease. Most interestingly, the seven variants together were also associated with a higher risk of coronary artery disease and heart attacks.
Previous evidence had already suggested that shorter telomere lengths were associated with increased heart disease risk. Now this new evidence strongly suggests that biological aging plays an important role in causing coronary artery disease, the most common cause of death in the entire world. It also partly explains why some patients develop it early and others don't develop it at all, even if they carry other risk factors.
Finally, these findings suggest that manipulating our telomere length could have many exciting health benefits. Indeed, experimental data has shown that lengthening telomere length can slow down - and in some cases even reverse - age-related changes in organs.