This is when aging speeds up
Key Takeaways
A new study found that the levels of most molecules in the body undergo especially rapid change around two specific ages, potentially impacting the risk of age-related diseases.
Along with changes at both ages related to cardiovascular health, skin, and muscle, the researchers identified age-specific molecular changes.
Still, several lifestyle modifications may counteract such changes and help people age healthily.
The levels of molecules and microorganisms in the body undergo two periods of rapid change during an individual’s life span, at around age 44 and 60, which may impact the risk of age-related diseases. This is according to a study by Stanford Medicine, published in August 2024 in the journal Nature Aging.[]
“We’re not just changing gradually over time; there are some really dramatic changes,” said senior author Michael Snyder, PhD, in speaking to the press.[] “It turns out the mid-40s is a time of dramatic change, as is the early 60s. And that’s true no matter what class of molecules you look at.”
Findings surprise the researchers
The timing of the study coincides with Healthy Aging Month. During September, the NIA is running activities and events to highlight recent scientific advances, longevity insights, and actions people can take to maintain their independence as they age.[]
While previous research explored linear changes during aging, the Stanford Medicine investigators noted that the risk of age-related diseases, including Alzheimer’s and cardiovascular disease, does not rise incrementally with age.
The study included 108 California residents (51.9% female), aged 25–75 (median, 55.7), and with a body mass index of 19.1 kg m2–40.8 kg m2 (median, 28.2 kg m2). A previous study with the same cohort found that aging of the kidneys, liver, metabolism, and immune system varied among individuals. In the new study, the researchers tracked age-related changes in more than 135,000 different microbes and molecules, including RNA, proteins, and metabolites, representing around 250 billion distinct data points. They collected blood, stool, skin, oral, and nasal swab samples every 3–6 months and tracked participants for a median of 1.7 years, with a maximum follow-up of 6.8 years.[][]
The researchers found that 81% of the molecules and microbes showed nonlinear fluctuations in number.
Clusters of molecules with the largest changes occurred most often in people at two time points: in their mid-40s and in their early 60s. Dr. Snyder said the researchers expected the changes in the early 60s but found those in the mid-40s a little surprising.
For individuals in their 40s, notable changes occurred in the number of molecules linked to alcohol, caffeine, and lipid metabolism, and also to cardiovascular disease, skin, and muscle. For individuals in their 60s, the changes were related to carbohydrate and caffeine metabolism, immune regulation, kidney function, and cardiovascular disease.
Menopause link
Initially, the researchers assumed that menopause or perimenopause could explain the changes in the female cohort, skewing the results. However, the researchers separated the group by sex and found molecular fluctuations in men in their mid-40s as well.
“This suggests that while menopause or perimenopause may contribute to the changes observed in women in their mid-40s, there are likely other, more significant factors influencing these changes in both men and women,” said first author Xiaotao Shen, PhD.[]
"Identifying and studying these factors should be a priority for future research."
— Xiaotao Shen, PhD
Lifestyle interventions
Dr. Snyder noted that some molecular changes may be linked to lifestyle rather than biological factors. Still, whatever the cause, people should focus on their health, especially in their 40s and 60s, the researchers suggested.
Interventions may include decreasing alcohol consumption for individuals in their 40s, when the ability to metabolize it slows, or increasing exercise to protect cardiovascular health and maintain muscle mass at both ages.
“I’m a big believer that we should try to adjust our lifestyles while we’re still healthy,” Dr. Snyder said.[]
The NIA highlights many lifestyle actions individuals can take to help them age healthily.[] For physical health, the NIA recommends regular physical activity, such as brisk walking and yoga; healthy eating by following the Mediterranean or low-salt diet; sleeping well with a regular sleep schedule; quitting smoking; avoiding or limiting alcohol consumption; and visiting the doctor yearly, or more if needed, for health screenings.
For mental wellness, the NIA recommends avoiding loneliness by staying connected with others; managing stress via meditation, physical activity, and participating in enjoyable activities and hobbies; and seeking treatment for depression.
Related: A nasal spray to cure loneliness
For cognitive health, the NIA recommends avoiding smoking or drinking heavily; following a Mediterranean diet; participating in 150 minutes of weekly moderate-to-vigorous intensity exercise; and engaging in mentally stimulating activities, such as playing games, writing letters, and reading.
What this means for you
Dramatic shifts in the number of molecules in the body associated with age-related disease occur at around ages 44 and 60. While changes related to cardiovascular health, skin, and muscle may be expected as people age, the abrupt nature of the changes is a striking finding and applies to other age-specific molecular changes as well. Still, a number of lifestyle factors, including physical activity, a healthy diet, regular doctor visits, and mental wellness, may counteract such changes and help promote healthier aging.