Most people are exposed to the concept of “longevity” only in their 60s or 70s, sometimes after the onset of chronic illnesses or a significant decline in physical and cognitive abilities. However, current science clearly points to the opposite and even sets us a deadline. The real difference in health and in healthspan (the length of healthy life) is built already in the fifth decade, around the ages of 40–50. This is a unique window of opportunity in which it is possible to significantly slow down aging processes and even reverse some of them.
A recent study from Stanford University showed that at age 40, a biological “jump” occurs: Changes in proteins, metabolic pathways, the microbiome, hormones, and muscle strength. These are quiet changes, sometimes imperceptible, but they are an early sign of the beginning of an acceleration in aging processes. In addition, around age 40, an accelerated decrease in muscle mass begins (early sarcopenia), impairment in mitochondrial function, and the appearance of subtle hormonal changes – in women (perimenopause) and in men (gradual testosterone decline).
The good news is that if action is taken in time, it is possible to significantly slow the pace of these aging processes and even reverse some of them.
Why is intervention at this age so effective?
1. High recovery capacity – the body’s systems are still biologically flexible and able to respond quickly to lifestyle changes.
2. Prevention of cumulative damage – mechanisms such as telomere shortening, accumulation of senescent cells, and oxidative damage progress over time. Early intervention slows the pace and prevents reaching a damage threshold that cannot be reversed.
3. Metabolic health at its peak – most people at age 40 still do not suffer from underlying conditions such as diabetes or heart disease, which allows for real prevention and not just treatment.
The brain and cognitive implications
Alongside the physical changes, already in the 40s there is a gradual decline in the volume of the hippocampus (the brain’s memory center) and in information processing speed. Aerobic physical activity, tailored nutrition, and encouraging the creation of new neural connections (neuroplasticity) at this age may preserve optimal brain function for decades ahead.
6 things you can start doing at age 40 that will impact you two decades ahead
- Biological age testing – including hematological clock, metabolic markers, and chronic inflammation indices.
- Preserving muscle mass – incorporate strength or resistance training at least twice a week.
- Optimizing sleep – identify your personal chronotype and adjust your sleep habits and daily routine accordingly.
- Nutritional balance – a diet rich in vegetables and fruits, quality protein, and limiting processed food and sugar.
- Hormonal testing – early detection of changes and correction as needed.
- Stress management – reducing chronic cortisol through mindfulness practice, breathing techniques, or physical activity.
<br>A smart investment
Age 40 is not “the beginning of the end”; it is an opportunity for a new beginning. A smart investment in your body and mind now will allow you to reach your 60s and 70s with more energy, sharp brain function, and stable health. Those who adopt a proactive approach in midlife will maintain high functional ability, significantly reduce the risk of chronic diseases, and increase the chance of aging in a healthy, active, and energy-filled way.
This window of opportunity will not remain open forever, and each year you wait, the body may accumulate additional cellular damage that is difficult to reverse. The difference between starting today and delaying by a decade may be the difference between life with limitations and life full of movement and smiles.
Prof. Tzipi Strauss is the Director of the Longevity Center at Sheba Medical Center, Tel Hashomer.