What is Functional Medicine, and what is its relevance in modern healthcare and wellbeing?

Mirthe Precision Health
9 min readFeb 27, 2023



The first wealth is health.

Ever pondered about the difference in lifespan vs health span? Although average life expectancy has increased dramatically in the last 100 years, this has not been accompanied by an equivalent increase in healthy life expectancy (Source).

Age-associated disease such as cardiovascular (i.e. stroke, heart attacks), type 2 diabetes, neurodegenerative (i.e. Alzheimer’s, Dementia, Parkinson), and others, render ‘old age’ (with the onset getting younger) into an often times dreaded time period, dependent on medications and declining bodily and cognitive functions. We survive rather than thrive.

Even throughout early life we are faced with an epidemic of conditions such as autoimmune (i.e. multiple sclerosis, lupus, chronic inflammatory bowel disease, rheumatoid arthritis), obesity, diabetes, autism, ADHD, anxiety and depression, PMS, endometriosis, IBS, chronic fatigue, fibromyalgia, cancer, and many other problems that can reduce quality of life significantly.

What do health, wellbeing & anti-ageing mean?

For most of us, we wish to live a long and fulfilled life, whether that is because we would like to see our grandchildren grow old, whether we feel we have a purpose on this planet we would like to yet achieve, or simply because we enjoy living. In order to fully live, we don’t want to just live long, but, most often more importantly, have the cognitive ability to achieve our dreams and goals, a working memory and a balanced mood that allows us to be in charge of our emotions and actions. We’d like a strong body that allows us to do daily and joyful activities without injury or pain, to feel energetic, and to look radiant and youthful. All this equates to quality of life for most of us, and has in recent years been termed as health span.

What are Functional Medicine & Precision Health?

Functional Medicine is an integrative health care approach based on the newest cutting edge research findings by leading scientists in medicine, biochemistry, genetics and biotechnology. It seeks to find, prevent and treat the root causes of disease, degeneration and ageing.

Rather than naming a disease and genetic risk (for example Alzheimer’s and its APOE4 gene) and treating its symptoms once they have developed, Functional Medicine looks at the underlying biochemical (im)balances that have been shown by research to predispose and contribute to the actual expression of Alzheimer’s through modifiable factors such as inflammation, blood sugar (Alzheimer’s has also been termed diabetes 3 recently due to its high correlation with elevated blood sugar over long periods of time), heavy metal exposure such as aluminum, gut microbiome imbalances, certain nutrient deficiencies, lack of deep sleep which reduces the glymphatic system’s capacity to clear out amyloid plaques, and more.

Functional Medicine looks at the underlying biochemical processes and their practical implications for targeted dietary and lifestyle recommendations, such as

  • Low grade inflammation
  • Free radical damage, repair & antioxidant levels
  • Detox capacity of liver, kidneys, lymph etc
  • Metabolic health (insulin resistance, blood sugar regulation etc)
  • Gut health such as gut microbiome status
  • Chronic lingering infections such as HPV, Epstein Barr virus, Candida, H. Pylori etc
  • Nutrient adequacy & deficiencies
  • Meal timing & circadian rhythm
  • Hormones and neurotransmitter

and more.


According to the UCLA, most treatments and health strategies have been designed with the average person in mind. This approach works for some patients, but not for others. We know each person is unique. Where we live, our genetic makeup, our family medical history and our lifestyle choices all contribute to our health and well-being. Precision health takes into account differences in people’s genes, environments and lifestyles and formulates prevention strategies based on the individual’s unique background and conditions.

Genetics vs epigenetics

We used to believe that our genes were our destiny. Many are scared illness like Alzheimer’s, cardiovascular or cancer, etc ‘running in the family’.

And while there are a few diseases that are ‘monogenic’, meaning they are triggered by one gene, and symptoms likely will show up very early on in life (and currently not much can be done about these (yet)), most of the ailments that plague humans in this century are not monogenic, but polygenic (a combination of different genes), and, most importantly, have to be triggered by epigenetics.


Epigenetics mean ‘surrounding our genes’. In simple words, our environmental, dietary and lifestyle exposures. The field of epigenetics has gained very large interest in research, as where once believed that ageing and illness was coded for by our genes, we now know that what we do and expose ourselves to (our ‘epigenome’) has a very large impact on which genes get turned on or off, whether we display health or disease.

Think of it as the old nature vs nurture debate.

Research shows that when identical twins are taken apart at birth and are exposed to very different lives, such as that one grows up in a nurturing environment, with good food and exercise choices, and the other being less lucky, growing up in (for example) a hostile environment, such as a violent or substance abusing household, with a diet lacking nutrients, etc. Despite having the exact same genes, when their health status gets checked later in life, they display very different health profiles. One may be the picture of perfect health, where the other may be suffering from cancer, cardiovascular, neurological or metabolic disease.

What happened? We all have certain genetic weaknesses and strengths, also called SNPs (single-nucleotide polymorphisms), or ‘mutations’. That is what makes each of us unique. Our epigenetics (lifestyle exposures) decide whether we play to our strengths or to our weaknesses, which genes get turned on and which off.

DNA health testing

We can run DNA tests nowadays to check for SNPs, to find out our unique genetic weak or strong features. For example one person may be more prone to peeing out zinc and vitamin B6 when they are stressed, which could render them deficient in those essential nutrients more easily than someone without that SNP.

Or one may have a SNP that makes a person slightly more prone to inflammation if they are sleep deprived, or less able to convert plant based omega 3 precursors such as found in flaxseeds and walnuts into the active brain and heart protective forms DHA and EPA.

Predictive biomarker

Regardless of whether we have tested our genes or not, much more important, in my humble view, is it to do regular predictive biomarker testing, to see where you are currently standing on the spectrum of optimal health vs ageing and disease, whether you are currently playing to your strengths or weaknesses. If ‘sludge’ is starting to build up, and if so, why and what can be done to reverse it day-to-day.

This is why I like to run a panel of the most important biomarkers.

Research suggests that regardless of genetics, we may be turning on or off certain genes, just by lifestyle choices. One may intuitively eat a diet high in zinc or fish, or get plenty of sleep, and therefore have adequate nutrient levels and no inflammation, despite those SNPs, where another person may not have those SNPs, but their lifestyle renders them deficient and inflamed regardless.



You have gotten the results of your latest ‘annual’ or GP check up, and all is ‘just fine’?

Did you know that most reference ranges that laboratories use are based on an average of the population? No, not of optimally healthy people, but the overall population.

Just because your last health check said that ‘everything is fine’, and all results are in ‘normal

ranges’, some of them may be on either end of that ‘normal range, and already contributing to sludge and rust building up in that clockwork of health, preventing your body from running optimally and smoothly. If that persists over time, what may have been suboptimal for some time, can turn into a real problem ‘all of the sudden’.

That is why within Functional Medicine we place your results into the stricter ‘optimal’ ranges (where these exist), so that you can decide yourself if you are happy to run on suboptimal and let that rust build up over time, or if you want to be proactive and make targeted changes.


Scientists have established ‘9 hallmarks of ageing’ (Source). In nerdy terms, these are

  1. Genomic instability
  2. Telomere attrition
  3. Epigenetic alterations
  4. Loss of proteostasis
  5. Deregulated nutrient sensing
  6. Mitochondrial dysfunction
  7. Cellular senescence
  8. Stem cell exhaustion and
  9. Altered intercellular communication

Much research is dedicated to finding drugs that target and modify these pathways. Within Functional Medicine, we aim to optimise the underlying pathways through targeted dietary, lifestyle and supplemental adjustments, rather than drugs with potential negative side effects.

All sounds complicated and too far removed from day-to-day?

That’s where our Functional Medicine and Precision Health approach come into play. Cardiovascular disease, neurodegenerative conditions like Alzheimer’s and Parkinson’s, mood disorders like depression, hormonal problems like infertility or lack of libido, fatigue, cancers, type 2 diabetes, obesity, joint pains and autoimmune conditions like Hashimoto’s thyroiditis, Multiple Sclerosis or Rheumatoid Arthritis. What seem like very different conditions, and they sure are in their symptoms and severities, the underlying systems gone wrong are (mostly) the same.

Research shows that

  • Low grade systemic inflammation (also termed ‘inflammageing’)
  • Excess free radical damage (oxidative stress)
  • Blood sugar imbalances and metabolic malfunctioning (insulin resistance)
  • Nutrient and building block excesses and deficiencies
  • Methylation problems (more on what methylation means later)
  • An overstimulation of our fight-or-flight nervous system and cortisol away from our rest-and- digest nervous system
  • Gut microbiome imbalances and chronic lingering infections
  • Overburdened detoxification system (liver, kidneys)

are at the root of all of them, triggering defects in all of our organs and systems, causing excess damage to our genetic coding, rusting and degradation of our cells.

The great thing is that each of them can be influenced by our daily choices.

In order for you to become the CEO of your health and turn the suggested changes into a new lifestyle rather than another diet’s wagon to fall off, I believe it is important for you to understand at least the basics of that clockwork of health that underlies our everyday functions, and either leads to optimal cardiovascular, brain and mood, digestive health, energy levels, hormone balance and weight or decline.

I believe knowledge is power, and would like for you to be able to make educated choices, rather than another fad diet’s wagon to fall off.

If you’d like to find out more on the different underlying factors contributing to either optimal health, or decline and degeneration, aka ‘sludge’, and how to optimise your daily routine for best results, join me in one of my next 4 weeks workshop series where I explain everything step by step in weekly live (Zoom) sessions (= Group coaching and Q&As!).. or sign up for my 4 week Health Reset course, which has all content in pre-recorded videos plus pdf worksheets, that you can go through at your own time and pace!

Comment below if you found this to be helpful, or email me at support@ functionalmedicine.me.uk — I’d love to hear from you!



Mirthe Precision Health

Functional Medicine Practitioner. Hormones, epigenetics, health optimisation. IG/ TikTok/ Youtube/ Fb: @mirthe_precisionhealth, www.functionalmedicine.me.uk,