New research has proven the sudden decline that a person feels at a certain age, noting that many molecules and microorganisms increase or decrease significantly between the ages of 44 and 60.
Stanford University scientists, who published their study yesterday in the journal Nature Aging, evaluated thousands of different molecules in people aged 25 to 75, as well as their microbiomes — the bacteria, viruses and fungi that live inside and on the skin — and found that their abundance, for the most part, does not change gradually and temporally.
In contrast, two periods of rapid change occur throughout life, on average at ages 44 and 60.
“We’re not just changing gradually over time, there are actually radical changes. It turns out that the mid-40s are a time of radical changes, just like the early 60s,” said Michael Snyder, who believes they are likely to have an impact on health.
Stanford University highlighted in a statement that the number of molecules associated with cardiovascular disease showed significant changes in both cases, and those related to immune function changed in people aged 60 years.
Scientists used data from 108 people they followed to better understand the biology of aging.
Among other things, they found four different age profiles (aging patterns) that show that the kidneys, liver, metabolism and immune system age at different rates in each person.
The researchers analyzed biological samples every few months for several years, tracking thousands of different molecules, including RNA, proteins, and metabolites, as well as changes in the participants’ microbiomes.
They observed that molecules and microbes showed changes in their abundance, increasing or decreasing. About 81 percent of all molecules studied showed nonlinear fluctuations in number, meaning they changed more at certain ages than at other times, from their 40s to their 60s.
The fact that so many dramatic changes occur in the early 60s may not be surprising, Snyder says, since many risks for diseases and other age-related phenomena are known to increase at this stage of life.
The sheer number of changes in the mid-40s was surprising. At first, the scientists assumed that menopause or perimenopause caused major changes in women, skewing the entire group, but when they divided the study group by gender, they found that the change also occurred in men around age 40.
“This suggests that while menopause or perimenopause may contribute to the changes that occur in women in their 40s, there are likely other, more important factors that influence them in both men and women. Identifying and studying these factors should be a priority,” said Xiao Tao, of Nanyang Technological University in Singapore.
In people aged 40 years, significant changes were observed in the number of molecules associated with alcohol, caffeine and fat metabolism, cardiovascular diseases, skin and muscle.