Focus & Memory for Now, Brain Health for the Future? Part 2

In part 1 of this article, we discussed why elevating your brain is so important for your professional success. Now, it’s time to talk about brain health in the long run. Let’s talk about mental longevity.

Why is brain health important later in life?

As a population, we are living longer but at the same time, we are spending more years in poor health. According to the WHO, 50 million people worldwide have dementia, with nearly 10 million new cases each year. In fact, “dementia is one of the major causes of disability and dependency among older people worldwide”2. Alzheimer’s disease (AD) contributes to around 60-70% of cases of dementia 2, and has a debilitating impact on later quality of life. Hence, it’s an important topic in longevity research. 

THE BRAIN

Let’s begin this section with a brilliant passage written by Sir M. Marmot in 20153:

“A chess grand master (…) complained that he used to plan nine moves ahead. Now at his dotage he was reduced to five moves ahead. When he died, soon after, he was found to have (…) advanced Alzheimer’s in his brain. He noted a marked decline in his cognitive ability, yet he was still functioning at a level most of us could only dream of. The point is that if you start from a high level, even with the inevitable toll of age, you can still function at a high enough level (…) to flourish.”

Neuroplasticity refers to our brain’s ability to physically change and reorganize itself. Our brain remains a dynamic organ throughout the life course 4 with the ability to synthesise new nerve cells. Building and maintaining ‘brain power’ has been associated with vigorous longevity, health, happiness, and wellness 4. Evidence suggests that exercise, intellectual stimulation (e.g. puzzles) and managing chronic stress and healthy eating 5 can maintain a healthy brain. 

GENETICS

AD develops from a combination of factors. The biggest risk factors for late-onset AD are older age (65 or older), having a family history of the disease, and carrying the Apolipoprotein E (ApoE) ε4 allele 6. ApoE plays an essential role in the transport of lipids and in the repair of brain injury. Since AD is multifactorial, having the allele does not single-handedly determine your risk. Furthermore, risk can be mediated; for example exercise, intellectual stimulation, social contact (e.g., contacting family and friends), and healthy eating are some of the available non-pharmacological strategies against AD 6.

THE IMMUNE SYSTEM

The term ‘inflammation’ has a bad rep. It is often thrown around in a misleading way. Before we dig any further, a clarification is needed. It is important to understand that the immune response of inflammation is critical. It’s our body’s response to pathogens and is also important for tissue repair, regeneration and remodelling 7. However, in recent decades, several diseases have been associated with what’s called chronic inflammation. These include obesity, depression, stress as well as burnout symptoms. Chronic inflammation is also observed in cognitive impairments such as AD, as well as lifestyles with poorer health outcomes, such as the Western Diet. Whilst association does not mean causation, abnormal blood inflammatory markers may warrant further investigation. 

THE GUT

Our lifelong cooperation with the gut starts at childbirth, so clearly it is important for health. But what about cognition specifically?

“Gut bacteria produce neuroactive compounds and can modulate neuronal function, plasticity and behavior. Furthermore, intestinal microorganisms impact the host’s metabolism and immune status which in turn affect neuronal pathways in the enteric and central nervous systems” [8]. The gut is often referred to as an endocrine organ, working alongside our hypothalamus, thyroid and other endocrine glands. 

Scientists recognise that the gut may be an important player in ageing and related neurological diseases such as stroke, Alzheimer’s and Parkinson’s [8]. It appears that the microbiome-gut-brain axis plays a crucial role in neurological disorders and that certain alterations in the microbiota lead (dysbiosis) to increased inflammatory reactions in stroke, Parkinson’s Disease and Alzheimer’s Disease in animal models.  

The  current scientific consensus is that a diverse and abundant microbiota, where the phylum Firmicutes and Bacteroidetes represent 80-90% of the total gut microbiota is associated with better health [9]. Such favourable composition is referred to as “symbiosis”.

LIFEHACKS FOR BETTER BRAIN HEALTH & FOCUS

DIET 10, 11

A 2019 study looked at the neuroprotective effects of different dietary patterns and concluded that “adherence to a healthy diet can decrease oxidative stress and inflammation and accumulation of amyloid-β and consequently can decrease the risk of AD”. Nutrition studies are extremely complex to design, so finding specific “neuroprotective” foods is nearly impossible – for this reason, scientists study dietary patterns instead. Major healthy dietary patterns that have neuroprotective evidence are:

• Mediterranean diet (MD)
• Dietary approaches to stop hypertension (DASH) diet
• Mediterranean-DASH intervention for neurodegenerative delay (MIND) diet

Also, dietary seafood, soy-based foods, capsaicin-rich, high-protein, and low-fat diet were found to decrease oxidative stress and inflammation and accumulation of amyloid-β. On the other hand, it was concluded that a high intake of fat and sugar-sweetened beverages, can promote oxidative stress and inflammation and accumulation of amyloid-β and subsequent development of AD.