How well we can concentrate, remember, and learn new things shapes our everyday lives. But like muscles and blood vessels, the brain also changes over the course of life. Some abilities slow down, while others remain remarkably stable. At the same time, there is growing interest in which factors influence mental fitness and how brain health can be supported in the long term.
Research shows that mental and physical health are closely linked. Exercise, sleep, nutrition, and social contacts play a role, as do blood pressure, blood sugar, and other metabolic values. In addition, the brain's ability to adapt to new demands is important.
The goal is not to stop every age-related change. What matters most is which habits and living conditions can help maintain mental performance for as long as possible.
Table of Contents
- How the brain changes over the course of life
- Which factors influence brain health
- Exercise as an important factor for the brain
- Staying mentally active and learning new things
- Sleep and regeneration for a high-performing brain
- Nutrition and brain health
- Social contacts and mental health
- What can be practically implemented in everyday life
- Brain health is a lifelong task
- Sources
How the brain changes over the course of life
The human brain remains malleable even in adulthood. It processes sensory impressions, stores memories, and adapts its activity to new demands. This adaptability is known as neuroplasticity. It is based, among other things, on nerve cells changing their connections and neural networks working differently together through new experiences.
With increasing age, various processes change. Brain volume gradually decreases in certain regions, communication between nerve cells can slow down, and blood flow changes. Areas involved in memory, attention, and planning are particularly affected.
However, not all mental abilities age in the same way. Processing speed and working memory may decline over the course of life. Vocabulary, experiential knowledge, and certain forms of long-term memory, on the other hand, often remain stable for a long time or benefit from accumulated experience.
Why memory and processing speed age differently
Processing speed describes how quickly information is received and further processed. In many people, it gradually decreases with increasing age. Working memory, which keeps information available in the short term, can also become less efficient.
Long-term memory should be viewed more nuancedly. While remembering new events or freely recalling information may become more difficult, familiar knowledge often remains well preserved. The ability to recognize connections and incorporate experience can also persist for a long time.
Such changes are partly part of normal cognitive aging and are not automatically an indication of illness. However, if memory problems increase and significantly impair everyday life, a medical evaluation is advisable.
Cognitive reserve and mental resilience
People with similar changes in the brain can show very different mental performance in everyday life. One explanation for this is cognitive reserve. This refers to the brain's ability to remain functional despite age-related or pathological changes.
Education, work experience, social activities, and mentally demanding occupations are associated with greater cognitive reserve. They can help the brain flexibly use different neural networks to tackle tasks.
However, cognitive reserve is not a shield and no guarantee that dementia will be avoided. Rather, it explains why people cope differently well with changes. Later life experiences and new challenges can also help people stay mentally active.
Which factors influence brain health
Mental performance depends on biological prerequisites, environmental conditions, and lifestyle. Factors that affect the blood vessels, metabolism, and nervous system over many years are particularly relevant.
The Lancet Commission on dementia prevention summarized a total of 14 modifiable risk factors in 2024. These include high blood pressure, diabetes, smoking, physical inactivity, excessive alcohol consumption, social isolation, and untreated hearing loss. Untreated vision loss and elevated LDL cholesterol levels in middle age were newly added.
Researchers estimate that a considerable proportion of dementia cases are theoretically linked to these factors. This estimate describes associations at the population level. It does not mean that individual illnesses can be reliably prevented, nor does it allow for individual predictions.
Blood pressure, blood sugar, and cholesterol
Persistently high blood pressure also puts pressure on the small and large vessels in the brain. Over time, vessel walls can be damaged, blood flow can change, and small vascular damage can occur. Such changes can affect attention, processing speed, and memory.
Diabetes and persistently high blood sugar levels are also relevant. They can impair vascular function and promote inflammatory processes. Other metabolic changes, such as elevated blood lipid levels or obesity, are often also involved.
LDL cholesterol is also classified as a modifiable risk factor for dementia. The associations are likely linked, among other things, to vascular changes and long-term strain on the metabolism.
Blood pressure, blood sugar, and blood lipids are therefore not only relevant for cardiovascular health. Whether and what treatment is advisable should be assessed medically on an individual basis.
Do not underestimate hearing and vision
Sensory abilities also influence how intensively people interact with their environment. Untreated hearing loss can make conversations difficult and limit social activities. Vision problems can also lead to people participating less in everyday life and avoiding mentally stimulating activities.
The Lancet Commission counts untreated hearing loss and untreated vision loss among the modifiable risk factors for dementia. This does not mean that every hearing or vision impairment leads to cognitive problems. However, it underscores that regular check-ups and appropriate care are also relevant for brain health.
An important study on this is the ACHIEVE study, which was published in the specialist journal The Lancet in 2023. Adults between 70 and 84 years with untreated hearing loss either received hearing aid provision with audiological counseling or general health counseling. In the overall evaluation, there was no significant difference in cognitive decline after three years. However, in a pre-defined subgroup with a higher baseline risk, the result was more favorable for the hearing intervention. The study suggests taking hearing loss seriously. However, it does not prove that hearing aids generally protect against cognitive decline.
Exercise as an important factor for the brain
Physical activity does not only affect the muscles, heart, and metabolism. The brain also responds to regular exercise. During physical exertion, blood flow and oxygen demand increase. At the same time, neurotransmitters and growth factors involved in the adaptability of the nervous system change.
The Brain-Derived Neurotrophic Factor, or BDNF, plays an important role in this. This growth factor is involved in the development and function of nerve cells as well as in synaptic plasticity. Physical activity can influence BDNF signaling. However, the extent to which these changes have a long-term effect on mental performance is not yet fully clear.
The hippocampus is particularly interesting. This brain region is essential for forming new memories. A meta-analysis of randomized studies from 2024 investigated whether endurance training affects the volume of the hippocampus in healthy older adults. The evaluation included eight studies with a total of 554 participants. Although physical fitness improved through the training, no statistically significant effect on hippocampal volume could be demonstrated. The results show that the positive effects of exercise on brain health cannot be reduced to a single measure.
Which type of exercise is advisable
For brain health, no specific sport is decisive. What matters more is regular exercise that can be integrated into everyday life in the long term.
Endurance activities such as brisk walking, cycling, swimming, or dancing support cardiovascular fitness. Strength training complements them by maintaining muscle strength and physical independence. Coordination exercises and learning new movement sequences additionally challenge attention and motor control.
The World Health Organization recommends adults engage in at least 150 to 300 minutes of moderate or 75 to 150 minutes of intense physical activity per week. In addition, the large muscle groups should be strengthened on at least two days. For older people, balance exercises are also advisable.
Consistency is more important than perfection. Those who have been inactive for a long time can start with short walks and gradually increase the duration.
Staying mentally active and learning new things
The brain adapts to the demands it regularly faces. Learning new skills, solving complex tasks, or familiarizing oneself with unfamiliar topics activates different neural networks. Such experiences can contribute to cognitive reserve.
Mental training does not have to consist of special puzzle programs or apps. Learning a new language, playing a musical instrument, reading a challenging book, or familiarizing oneself with an unknown subject area are also ways to stay mentally active.
However, a distinction must be made between training individual skills and a comprehensive improvement in mental performance. Someone who regularly practices a specific memory game may become better at it. However, it is not automatically proven that this training effect transfers to other cognitive areas or everyday life.
What research shows about cognitive training
The Finnish FINGER study is one of the best-known studies on a holistic approach to brain health. In the randomized study published in 2015, 1,260 adults between 60 and 77 years with an increased risk of cognitive impairment participated. One group received a combination of nutritional counseling, exercise, cognitive training, and regular monitoring of vascular risk factors over two years. The control group received general health information.
Participants in the intervention group showed, on average, a slightly stronger improvement in their cognitive test results. The difference was statistically significant, but not large. The study provides evidence that a combined lifestyle approach can positively influence mental performance in older age. However, it does not prove that this can reliably prevent dementia.
The US-POINTER study published in 2025 also investigated such an approach. More than 2,100 older adults with an increased risk of cognitive decline participated in a two-year program. A structured, more intensive intervention was compared with a self-implemented program. Both groups improved their cognitive test results. The structured group achieved a slightly greater increase on average. This suggests that regular support and a clear daily structure can help implement health-promoting habits.
Sleep and regeneration for a high-performing brain
During sleep, the brain processes information and consolidates memories. During so-called memory consolidation, newly acquired information is stabilized and linked with existing knowledge.
Sleep consists of several phases that alternate throughout the night. Deep sleep, in particular, plays an important role in consolidating declarative memories, such as facts and events. REM sleep is also involved in memory processes. The different sleep phases work together. Which processes are particularly important depends, among other things, on the type of stored information.
Another area of research is the so-called glymphatic system. Metabolic waste products can be transported out of the brain through this network of fluid spaces. Animal studies suggest that this process may be particularly active during sleep. How strongly these findings can be applied to human sleep and long-term brain health is not yet fully clear.
Consistently poor or too short sleep is associated with unfavorable cognitive developments in observational studies. However, the relationship is complex: sleep problems can be linked to health changes, but can also be caused by existing illnesses or mental stress.
In addition to sufficient sleep duration, consistency and subjective rest are crucial. Persistent sleep problems, heavy snoring, or signs of sleep apnea should be medically evaluated.
Nutrition and brain health
The brain continuously requires energy and depends on a sufficient supply of nutrients. Although it makes up only a small part of body weight, it consumes a considerable portion of the daily available energy. The cell membranes of nerve cells also contain fatty acids that are important for their structure and function.
Dietary patterns with a high proportion of vegetables, fruit, legumes, whole grains, nuts, and plant oils are particularly well studied. Fish can also be part of such a diet.
Mediterranean diet and MIND diet
The Mediterranean diet is frequently associated with favorable cognitive outcomes in observational studies. It is characterized by a high proportion of plant-based foods, olive oil as an important fat source, and a rather restrained consumption of red and processed meat.
A further development is the MIND diet. It combines elements of the Mediterranean diet with recommendations from the DASH diet, which was originally developed for blood pressure regulation. Green leafy vegetables, berries, nuts, whole grains, and legumes are particularly highlighted.
The results of the research should, however, be viewed with nuance. Observational studies do suggest that a stronger adherence to these dietary patterns may be associated with more favourable cognitive development. However, a randomised study on the MIND diet in 2023 found no significant difference in cognitive decline between the MIND group and the control group after three years. This suggests that no particular diet can currently be considered a proven protection against dementia.
Does the brain need additional supplements?
Supplements are often advertised as improving memory performance and mental fitness. However, for healthy people with no proven nutrient deficiency, there is no compelling evidence that additional vitamins or omega-3 fatty acids reliably prevent age-related cognitive decline.
The updated WHO guidelines from 2026 therefore do not recommend supplementation with vitamin B, vitamin E, omega-3 fatty acids, or multivitamins specifically to reduce the risk of cognitive decline or dementia unless there is a corresponding deficiency. A proven deficiency should, of course, be treated medically. This is, however, different from supplementation for general performance enhancement.
A balanced diet remains the foundation. Supplements replace neither a varied selection of foods nor the treatment of existing medical conditions.
Social contacts and mental health
Conversations and shared activities challenge the brain in different ways. People must listen, categorise information, respond to others, and formulate their own thoughts. At the same time, social contacts can provide emotional support and help cope with stress.
Social isolation and loneliness are associated in studies with an increased risk of cognitive impairment and dementia. However, the connections are not exclusively causal. People with early cognitive problems may withdraw more. Conversely, a lack of social interaction can take a toll on mental and psychological health.
Depression is also relevant. It can impair concentration, memory, and motivation. Persistent depressive symptoms should therefore not be dismissed as a normal part of ageing, especially in later life.
What matters is not the number of contacts, but whether social relationships are experienced as supportive and enable regular interaction.
What can be concretely implemented in everyday life
Research suggests that brain health should not be reduced to a single measure. Rather, several areas of life matter, which influence each other. Exercise, sleep, nutrition, and social activities complement the monitoring of health risk factors.
For everyday life, this means:
- Exercise regularly: Incorporate endurance training, strength exercises, and balance training.
- Stay mentally curious: Learn new skills, read, make music, or engage with challenging topics.
- Get enough sleep: Maintain regular sleep times and have persistent sleep problems checked.
- Eat a balanced diet: Regularly include vegetables, fruit, whole grains, legumes, nuts, and plant oils.
- Monitor risk factors: Keep an eye on blood pressure, blood sugar, and blood lipid levels, and seek medical treatment if necessary.
- Check hearing and vision: Recognise impairments early and seek appropriate treatment.
- Nurture social contacts: Consciously integrate interaction and shared activities into everyday life.
Not every measure needs to be implemented at the same time. Habits that remain realistic in the long term are usually more sensible than a highly ambitious short-term plan.
Brain health is a lifelong task
Mental fitness does not only emerge in later life. Education, exercise, nutrition, sleep, social relationships, and the treatment of health risk factors influence the brain over many decades.
Studies such as FINGER and US-POINTER illustrate that several measures together can influence cognitive performance in old age. However, the observed effects are limited and cannot be equated with a certain prevention of dementia. A single training programme, food, or supplement is also not a reliable solution.
Mental fitness does not mean that the brain remains unchanged. Rather, it means using its abilities, allowing new experiences, and viewing physical and mental health together.
Sources
- Livingston, G. et al. (2024): Dementia prevention, intervention, and care: 2024 report of the Lancet standing Commission. The Lancet, 404(10452), 572–628. https://doi.org/10.1016/S0140-6736(24)01296-0
- World Health Organization (2026): Risk reduction of cognitive decline and dementia: WHO guidelines, second edition. Geneva: World Health Organization. https://www.who.int/publications/i/item/9789240123557
- World Health Organization (2020): WHO guidelines on physical activity and sedentary behaviour. Geneva: World Health Organization. https://www.who.int/publications/i/item/9789240015128
- Salthouse, T. A. (2012): Consequences of age-related cognitive declines. Annual Review of Psychology, 63, 201–226. https://doi.org/10.1146/annurev-psych-120710-100328
- Stern, Y. (2012): Cognitive reserve in ageing and Alzheimer's disease. The Lancet Neurology, 11(11), 1006–1012. https://doi.org/10.1016/S1474-4422(12)70191-6
- Ngandu, T. et al. (2015): A 2 year multidomain intervention of diet, exercise, cognitive training, and vascular risk monitoring versus control to prevent cognitive decline in at-risk elderly people (FINGER): a randomised controlled trial. The Lancet, 385(9984), 2255–2263. https://doi.org/10.1016/S0140-6736(15)60461-5
- Baker, L. D. et al. (2025): Structured vs Self-Guided Multidomain Lifestyle Interventions for Global Cognitive Function: The US POINTER Randomized Clinical Trial. JAMA, 334(8), 681–691. https://doi.org/10.1001/jama.2025.12923
- Lin, F. R. et al. (2023): Hearing intervention versus health education control to reduce cognitive decline in older adults with hearing loss in the USA (ACHIEVE): a multicentre, randomised controlled trial. The Lancet, 402(10404), 786–797. https://doi.org/10.1016/S0140-6736(23)01406-X
- Balbim, G. M. et al. (2024): Aerobic exercise training effects on hippocampal volume in healthy older individuals: a meta-analysis of randomized controlled trials. Geroscience, 46(2), 2755–2764. https://doi.org/10.1007/s11357-023-00971-7
- Lutz, N. D., Harkotte, M. & Born, J. (2026): Sleep’s contribution to memory formation. Physiological Reviews, 106(1), 363–483. https://doi.org/10.1152/physrev.00054.2024
- Xie, L. et al. (2013): Sleep drives metabolite clearance from the adult brain. Science, 342(6156), 373–377. https://doi.org/10.1126/science.1241224
- Barnes, L. L. et al. (2023): Trial of the MIND Diet for Prevention of Cognitive Decline in Older Persons. The New England Journal of Medicine, 389(7), 602–611. https://doi.org/10.1056/NEJMoa2302368
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