Physical Health, Brain Health and Mental Health

Physical health is one of the determinant that can impact our brain health. Although it’s probably the aspect that is most commonly talked about, I’d love to expand a bit further about what falls under physical health and how it can impact brain health.

What falls under physical health as a determinant of brain health?

When addressing physical health, we can think about factors that can directly impact our health such as genetics, infections and diseases. As we know, genes are passed down from previous generations and although we have very little control over this process, they have the power to impact our brain structure and functioning. We know that certain type of infections such as meningitis, encephalitis and Zika virus can affect our brain directly by attacking the nervous system or by triggering systemic inflammation which can in turn trigger neuroinflammation. Other diseases such as cardiovascular disease, respiratory disease, diabetes and their associated risk factors (e.g. obesity & high blood pressure) can harm the brain as well. Stroke & dementia are great examples of how health associated risk factors can alter brain functions.

Then, there is a range of factors that fall under physical health that we have more control over. Those include maternal health, nutrition, exercise and other health behaviours such as quality of sleep and substance use. These factors have the power to enhance or lower our brain health but also to impact the development and functioning of the brain.

So how can overall physical health also impact our mental health?

Physical health and brain health are closely intertwined and have the power to influence one another. On one hand, what we feed our brain can hugely influence its functioning and on the other hand, our brain controls many aspects of our physiological processes (heart rate, hormones, etc.) which can also influence our physical health. Everything is connected.

Let’s take nutrition as an example. Research has shown that adequate nutrition is crucial in maximising brain development in our earlier years, but this remain true throughout the life course of an individual. We hear more and more about the gut-brain connection and how looking after our microbiome can directly impact our physical and mental health. You are probably familiar with this saying “you are what you eat”.  Feeding yourself good food has a real impact on how you feel and therefore can influence your mood, ability to cope with stress and mental health. Certain pesticides are also recognised as harmful for brain health. They can induce neuroinflammation which can in turn dysregulate the hypothalamus/ pituitary /adrenal axis, impact neural function and immune cell activation...which can all be linked to mental health challenges such as depression.

Another example, alcohol consumption impairs the functioning of our brain and can also alter brain development, both of which potentially having an impact on our ability to manage certain situation and decision making. In this instance, alcohol can lead to changes in brain chemistry which can worsen symptoms of anxiety, stress and depression.

Several research have also linked regular physical exercise to brain health as exercise stimulates neuroplasticity and increases the production of brain-derived neurotropic factor (BDNF) which in turn contributes to reducing inflammation in the body. [1] From a mental health perspective, exercise releases endorphins, increases the blood flow to the brain, promotes better sleep, can improve cognitive functioning and substantially improve mood, decrease anxiety and contribute to preventing serious mental illness such as depression.

The air that we breathe can impact our physical health and recent research demonstrate that air pollution can impact the development of the brain. Exposure to air pollution in pregnancy and childhood is linked to a smaller hippocampus (which is important for emotional functioning, learning and memory) and a larger amygdala (fear centre) by pre-adolescence.[2] These changes that can occur in the brain may make us more prone to developing mental health problems such as emotional lability, anxiety and reduce our ability to cope with stress.

How can reduced brain health impact your mental health?

When brain health has been compromised through ill health such as a stroke or say an accident resulting in a traumatic brain injury,  flow on effects can range wide for an individual. The ways in which an individual may have to adapt to new limitations can be really challenging physically and emotionally. Other life altering neurological disorders, such as dementia, can lead to mental health challenges not only for the person affected but also for their family.

Families navigating health problems, whether it originates from a neurological disorder or not, often find themselves faced with a number of external stressors. Left unaddressed, those stressors can feel overwhelming and start impacting a person's mental health.

Improving our mental health by optimizing our brain health

Prevention and adopting a healthy lifestyle can go a long way in maximizing our physical health. As I've demonstrated through this blog, there is a direct connection between our physical health, brain health and mental health.

There is a lot to take into consideration as they are closely intertwined, but we don't have to be intimidated by this. Because they are so closely linked, you may find that gradually altering some of the physical health determinants can have an important flow on effect on your brain health and mental health. It is never too late to start either. Every little steps you take to better your brain health will add up.

Which determinant of physical health do you think you can make adjustments on in order to give your brain and mental health the best chance to thrive?

I'm looking forward to read your comments to find out more about what you are planning to do.

[1]: de Sousa Fernandes MS, Ordônio TF, Santos GCJ,

Santos LER, Calazans CT, Gomes DA et al. Effects

of physical exercise on neuroplasticity and brain

function: a systematic review in human and

animal Studies. Neural Plast. 2020;2020:8856621.

doi:10.1155/2020/8856621.

[2]: Lubczyńska MJ, Muetzel RL, El Marroun H, Hoek

G, Kooter IM, Thomson EM et al. Air pollution

exposure during pregnancy and childhood and

brain morphology in preadolescents. Environ Res.

2021;198:110446. doi:10.1016/j.envres.2020.110446.