As we age, many of us begin to gain weight, especially after the age of 40. This is an all-too-common occurrence. It also means that some individuals may start to develop insulin resistance. The same person, with the same lifestyle and eating habits, experiences these issues in middle age. This suggests a link between age and insulin resistance.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3004429/
A study effectively illustrates this point. It found that insulin resistance becomes more prevalent with age. More importantly, elderly individuals with insulin resistance experience a 40% reduction in their mitochondrial oxidative and phosphorylation capabilities.