Exercise, avoiding stress and having a high level of intellectual activity help protect against Alzheimer's disease

In Western societies, Alzheimer's disease affects 10% of the population over 65. Just in Catalonia, there are almost 90,000 cases, and more than 800,000 in Spain as a whole. It is a very common degenerative disease but, so far, no drugs have been found that can cure it. Current effort is focused on early detection, palliating symptoms and, in the early stages, slowing down the disease's progression.

The neuroscientist Diego Redolar, director of the Cognitive NeuroLab research group and professor at the UOC's Faculty of Health Sciences, points out that there are certain habits that help our brain become more resistant to attack by the disease and delay the onset of symptoms.

• Exercise. Scientists disproved quite some years ago the belief that after a certain age in adulthood, the brain stopped creating new neurons. As Redolar explains in the book El Cerebro Cambiante (The Changing Brain) (Editorial UOC), "the process where new neurons are formed – neurogenesis – also takes place in adulthood". In this respect, regular physical activity is beneficial because it has been shown to promote the creation of new neurons in the hippocampus.
  
  Furthermore, practising sport oxygenates the blood and improves vascularization and blood supply to the brain and nerve tissue. It also helps preserve the neurons, which are particularly sensitive. "It is not the profusion of stimuli that triggers the birth of new neurons but the physical exercise we perform in response to these stimuli", explains the neuroscience specialist. Thus, "exercise is not only beneficial for forming new neurons; it also helps maintain balance and an optimal environment in our brain". Lastly, exercise also stimulates the release of a molecule that plays an important role in the experience-related rearrangement that takes place in the brain.
   
• High level of intellectual activity. "Middle-aged people who engage in a high level of intellectual activity – reading, doing crosswords, etc – generate what the experts call "cognitive reserve". This reserve, explains Redolar, is the brain's ability to cope with neural changes brought about by ageing or illness, thereby modulating the relationship between brain injuries and their clinical manifestations and limiting the negative impact on cognition. The effect, therefore, is "a delay in the emergence of symptoms".
  
  This has been shown in a number of studies using magnetic resonance. Individuals with a significant genetic load for developing the disease, or even those who already have it, have managed to delay the appearance of symptoms with this intellectual reserve which, somehow, has been able to offset the clinical factors. UOC course instructor David Bartrés-Faz has also worked in this field. He currently leads the brain health project Barcelona Brain Health Initiative, sponsored by the Institut Guttmann and Obra Social "la Caixa". The ultimate goal is to discover how healthy habits can impact on neural plasticity, which is the nervous system's intrinsic ability to modify its structure and neural connections to develop new abilities and adapt to changes.
   
• Avoid stress. If exercising oxygenates the blood, stress does the exact opposite, with devastating effects on the neurons. Therefore, stress must be avoided, seeking a healthy balance that stimulates the brain but without burning it, literally.