Preserving optimal brain health as we age is one of the most important goals in improving health span and lifespan. Nobody wants to live a long life with poor brain health; being socially present, mentally sharp and physically fit throughout life is what longevity medicine aims to achieve.
Our brain is the most complex organ in our body and enables all our movements, automatic behaviour, emotions, thoughts, memories, decisions, sensation perception and regulation of all organ functions.
Preserving brain health is as complex as the functions it performs. It includes maintaining integrity of brain structure and volume; preserving all functions, including learning, memory, reading and problem-solving; preserving mental function such as the processing of thoughts and feelings; and avoiding any brain diseases such as Alzheimer’s disease, stroke, mental health disorders and traumatic brain injuries.
Alzheimer’s disease is by far the most common of the neurodegenerative diseases and the most common cause of dementia. Like other chronic diseases, the disease develops over many years prior to the appearance of symptoms. It is a result of multiple factors − both modifiable and non-modifiable. The latter include age, genetics, family history and gender.
Older age is the greatest risk factor − the percentage of the population with Alzheimer’s increases dramatically after the age of about 65. It is, however, important to point out that it is not a normal part of ageing.
There is much we can do to prevent or reduce the chances of developing this debilitating disease and preserve brain health in general. Many of the lifestyle factors which support overall longevity, and in particular those that are beneficial to our cardiovascular health, are central to brain health.
Not smoking and limiting alcohol consumption to low or moderate amounts dramatically reduces your risk of developing dementia. Smokers are at about a 60% increased risk of dementia when compared to non-smokers. Stopping smoking will also gradually reduce your risk.
The benefits of exercise with respect to brain health cannot be understated
Getting sufficient and regular exercise and sleep are two crucial tools for optimal brain health. From the perspective of neurodegenerative diseases, sleep allows the brain to flush out waste products, such as those which are hallmarks of Alzheimer’s disease, which would otherwise lead to inflammation in the brain and cognitive impairment. Sleep also helps consolidate memories, whereas sleep deprivation is known to cause a rapid deterioration in mental health issues, including anxiety and depression.
Not regularly getting sufficient, quality sleep also indirectly increases your risk of developing Alzheimer’s due to increased blood pressure, as well as its significant impact on appetite. Maintaining a healthy blood pressure throughout life plays a very important role in both heart and brain health.
Hypertension disrupts blood flow which, in turn, would mean disrupted oxygen and nutrient supply to the brain. Monitoring your blood pressure regularly − particularly as it typically causes no symptoms when elevated − is vital to your overall health.
The benefits of exercise with respect to brain health cannot be understated. It exerts its benefits through various pathways, the most obvious being that it increases blood flow to the brain which is critical for brain health.
Regular physical activity also increases certain chemicals called growth factors (for example BDNF) which play a pivotal role in the growth and survival of the brain’s cells. Additionally, exercise also regulates the release of a variety of chemicals which have an anti-inflammatory effect on the brain – low-grade chronic inflammation is a common feature to the chronic diseases of ageing, including Alzheimer’s disease and its associated cognitive decline.
Exercise is, of course, also well known to boost mood which also has a positive effect on mental health. The type of exercise most likely to benefit brain health is likely to be a combination of aerobic, strength and skilled, high-intensity training. Going from no exercise to just three hours of well-structured exercise per week may reduce your risk of Alzheimer’s by some 50 per cent.
Exercise also indirectly affects other aspects of brain health such as metabolic health. Having sufficient muscle mass − which comes from strength training − is central to staving off the spectrum of metabolic disorders ranging from obesity to insulin resistance all the way to type 2 diabetes. Avoiding these conditions is vital to maintaining a healthy brain.
Several eating patterns such as the Mediterranean diet and the MIND diet also seem to support brain health, but this is secondary to maintaining a healthy weight. Also, despite much marketing of supplements, there are very few which have been proven to be beneficial to brain health. These include omega 3 fish oils, sufficient B vitamins, vitamin D and curcumin due to its anti-inflammatory effects.
Maintaining good oral hygiene to prevent gum disease and the associated chronic low-grade inflammation is another important, often overlooked, factor to consider when preventing the chronic diseases of ageing, including Alzheimer’s.
Another two modifiable factors which are particular to brain health are avoiding traumatic brain injury and hearing loss. Individuals with hearing loss are at a greatly increased risk of developing neurodegenerative diseases.
Philip Borg is a longevity medicine specialist, as well as a consultant interventional radiologist. He leads The Longevity Clinic at St James Hospital.