Incorporating a small amount of physical activity daily can have a significant impact on dementia prevention. Research conducted by scientists from Brazil and the United States suggests that if currently sedentary adults start exercising for at least ten minutes every day, it would be possible to avoid about 420,000 dementia diagnoses by the year 2050. This change would result in an estimated saving of up to R$ 16 billion in costs associated with the disease.
If physical inactivity were completely eradicated, the savings could reach R$ 23 billion, as detailed in the analysis published in 2025 in the Brazilian Journal of Psychiatry. The authors cross-referenced 2019 data from the National Health Survey, conducted by the Ministry of Health in collaboration with the Brazilian Institute of Geography and Statistics (IBGE), with information obtained from the Global Burden of Disease, carried out in the USA.
The findings demonstrate that 14.9% of dementia cases in Brazil are directly linked to physical inactivity, which differs from sedentary behavior. Physical inactivity refers to performing less than 150 minutes of exercise per week, the period recommended by the World Health Organization (WHO). Sedentary behavior, on the other hand, describes the time spent sitting, lying down, or reclining, characterized by low energy expenditure.
Natan Feter, one of the researchers and a physical education professional, commented that, from a population perspective, one in every fifteen global dementia cases can be attributed to physical inactivity, meaning that a new case every 42 seconds could be prevented with exercise practice.
Projections and Economic Impact
Projections indicate that the number of Brazilians living with dementia may increase from approximately 1.9 million in 2019 to 5.7 million in 2050, a growth mainly driven by population aging. This increase entails considerable financial consequences: seven years ago, the estimated cost of the illness in the country already totaled US$ 35.3 billion, with the largest portion of this amount linked to informal care provided by family members.
Exercise Benefits the Brain
In recent decades, science has accumulated substantial evidence on the role of exercise in maintaining brain health. Consistent physical activity improves cognitive functions, reduces the risk of cerebrovascular events, such as stroke, and stimulates processes related to neuron formation and survival. Feter, who works as an associate researcher at the Department of Biological Sciences at the University of Southern California, USA, emphasizes that all of this helps in understanding the protective effect of physical activity against dementia.
Sedentary behavior was also identified as a relevant risk factor, increasing the chance of developing the problem by percentages ranging between 17% and 30%. Geriatrician Thaís Ioshimoto, from Einstein Israelite Hospital, warns that individuals who spend more than ten hours daily in this type of behavior present an increased risk of dementia.
In contrast, activities performed while seated but that promote brain stimulation, such as memory games or reading, have not shown the same correlation with the disease. Ioshimoto states that in clinical practice, it is observed that more active elderly people have a lower incidence of dementia, which corroborates the idea that what is beneficial for the heart also benefits the brain, including a balanced diet, regular physical exercise, and blood pressure and cholesterol control.
The study also noted that the greatest benefits are achieved when a person starts some form of activity from scratch. Natan Feter emphasizes that every minute added to the routine reduces the risk of dementia.
The 10-Minute Goal
The proposal to focus on small amounts of physical activity arose from the realization that more demanding goals, such as meeting the 150 weekly minutes suggested by international guidelines, can be challenging for a large part of the population. Ten daily minutes can be achieved through a walk in the neighborhood, going to the gym, doing strength exercises at home, or simply standing for ten minutes a day.
Thaís Ioshimoto assesses that this goal is achievable by most people. In addition to physical gains, she mentions that among the elderly who start exercising, the benefits extend beyond physical fitness. She declares that any activity is valid, with movement being crucial, as exercise improves mood, promotes socialization, and often triggers other improvements, such as adopting a healthier diet.
Despite the results reinforcing the importance of individual decisions, the researchers point out that physical activity is intrinsically linked to social conditions, given that many work all day and spend hours commuting. When time is available, there are often a lack of safe places or appropriate infrastructure for sports practice. Feter concludes that physical activity must be viewed as a human right, arguing that besides encouraging small behavioral changes, it is vital to invest in public policies that expand access to such opportunities.