You’ve probably already recognized that there are countless different ways different people are improving their body composition, performance, and health status, and you might feel like it’s been a crapshoot figuring out what works best for you.
There are reasons for this discordance between what works for one of us but not the other, and reasons why you might be having a tough time making any progress even when you’re doing exactly “what you’re supposed to do”.
My previous post, “Demystifying the human body”, explored the idea that to some extent we have a pretty good understanding of how our bodies work, and that our cells respond to the various signals they receive to shape how we look, feel, and perform.
However, there were some key concepts missing from that post that are critical for you to understand as you start to shape the signals you’re sending your own body in an effort to improve your health and fitness.
While it’s true that we have a pretty good general understanding of the human body at the “macro” level, there are quite a bit of complicated mechanisms at play when we consider things at more of a “micro” level.
In this post, we’re going to explore some of the factors that make things so complicated, and clarify a bit why you might be having such a hard time figuring out how to eat, how to move, and how to live in order to lose fat, move well, and feel awesome.
I was tempted to title this post “Remystifying the human body”, but figured the current title would be a bit more reader-friendly 🙂
At the heart of every single thing that our cells do is a biomolecule called deoxyribonucleic acid, or “DNA”.
DNA is shaped like a spiraling ladder, the “sides” of which are made of phosphate and sugar, and the “rungs” of which are made of pairs of four molecules – guanine, adenine, thymine, and cytosine.
The arrangement of these four molecules form sequences that serve as instructions for our cells to produce proteins intended to serve specific tasks.
These specific sets of instructions are referred to as “genes”.
Interesting side note – have you ever seen the movie 1997 Ethan Hawke movie, “Gattaca”?
That title is actually a reference to how these four molecules are represented by the letters “G”, “A”, “T”, and “C” when describing their order within a given sequence of DNA.
Anyhow, there are an estimated 20,000-25,000 genes that dictate everything about us, including how tall we grow, the colors of our eyes, the straightness or curliness of our hair, and how our cells behave by coding for different proteins to perform different tasks.
For example, genes in the cells of our eyes code proteins for detecting light, genes in our blood cells code proteins for detecting oxygen, and genes in the cells in our muscles code proteins for getting ultra-jacked.
Not only do these genes determine more noticeable outward traits like how we look, but they also affect less obvious underlying physiological processes.
How we respond to different nutrients, how we respond to different training and exercise modalities, our chances of developing certain diseases, and nearly everything that factors into our fitness, health, and wellbeing is influenced by our personal genome.
It’s important to note than what we consider to be specific traits aren’t necessarily influence by individual genes.
For example, there are roughly 700 genes found to be associated with height, and 15 associated with the color of our eyes.
We inherit our genes from our parents, and even though you might think that the possible genetic combinations you might get from two parents is limited, you might end up with one of 8,324,608 possible combinations of their respective genes.
At a species level, the number of potential genetic combinations is thought to be a staggering 70,368,744,177,664.
Let that sink in – the number of possible genetically unique human beings is 700 times higher than the 107 billion humans estimated to have lived so far.
Unless you’ve got an identical twin, you are truly one of a kind as far as your genetic makeup is concerned.
Additionally, our genes don’t work in a “set it and forget it” manner – they can be turned on and off like switches, or “expressed”.
One of the factors that influences gene expression is “junk DNA”.
Only about 2% of our DNA acts as genes, directly involved in coding proteins; the remaining 98% is referred to as “junk DNA”.
This “junk DNA”, however, is not as insignificant as its name might imply, as it plays a role in how individual genes are or are not expressed.
Thus, even though all cells in a given human body contain the same genes, different cells might only end up expressing 10 or 20 percent of the genes that are present, partially due to the shape and influence of junk DNA.
The genes we inherited and the effects of junk DNA are not the only factors, however, that determine whether and how our genes are expressed.
Our DNA is surrounded by a set of chemical markers referred to as the “epigenome”, which we’re also learning has an influence on how our genes are expressed.
Similar to gene expression, these epigenetic markers aren’t set in stone and are influenced by environmental and lifestyle factors.
For example, exercise patterns, exposure to certain chemicals like bisphenol A (BPA), and even childhood abuse have been linked to changes in the epigenome, although the effects and mechanisms of these changes – at the epigenetic level, at least – are not quite fully understood.
Let’s go ahead and complicate things a bit further 🙂
Not only are genes passed from one generation to the next, but epigenetic adaptations can be passed on also.
For example, children of mothers pregnant during a famine in the Netherlands in 1944 demonstrated higher rates of obesity, diabetes, and schizophrenia, and had a higher rate of mortality seven decades later.
These children’s predisposition to disease is thought to be an effect of changes to the epigenome of the pregnant mothers and/or the unborn children during that famine.
If you want to read more about the generational epigenetic effect, you might read into a dude named Francis Pottenger and some experiments he performed with cats.
In a nutshell, not only do your inherited genes affect the specific eating, training, and other lifestyle habits you might need to be optimally fit and healthy, but also the epigenetic changes you’ve inherited – and those that have occurred in your own lifetime – affect these outcomes.
We’re not QUITE done muddying the waters yet.
So far, we’ve only covered the human genes that affect your health and fitness efforts; there are also non-human genes that affect how you look, feel, and perform.
Our bodies are also hosts to a variety of bacteria, yeast, and parasites living within our digestive systems, our mouths, and even on our skin.
Collectively, we’ll refer to this community of organisms as “the microbiome”.
While research on the effects of the microbiome is relatively limited, we started studying them more and are finding that they have a profound effect on our physical and even mental wellbeing.
The organisms living in our gut, for example, are linked to all sorts of health outcomes including diabetes, obesity, depression, and even cancer.
For example, some artificial sweeteners have been linked to alterations in the gut bacteria of mice that were shown to contribute to poor blood sugar regulation.
While this specific mechanism might or might not be applicable to you and me (we don’t know), it demonstrates how our eating habits might affect us through changes to our microbiome.
If you thought the number of possible genetic combinations were staggering, get this – there are thought to be 100 trillion bacteria living on and within the human body – ten times more than the 10 trillion human cells we’ve got to work with.
Similar to our genes and epigenetic markers, our microbiome is inherited from our parents (well, really our mothers), and are also affected by not only their lifestyles, but by ours.
There truly is no “one size fits all” solution
I’m sharing all of this with you for a few different reasons.
First of all, writing all of this out and ATTEMPTING to describe in an accurate, clear, coherent manner was a wonderful exercise for me to sort through and clarify my own thoughts and understanding of these concepts.
Second, awareness of these factors might help you better grasp all the different pathways that your choices influence your health, further demystifying your body.
Finally, this information should help explain why there’s so much variability in terms of how each of us responds to different dietary habits, training modalities, and lifestyles, and why there is truly no “one size fits all” solution.
There’s the not only the acute physiological responses of your actions to consider, but also the epigenetic and microbiotic (spellcheck doesn’t like that word, but we’ll run with it) responses to consider.
We’ve all got different genes, different epigenetic adaptations, and different microbiomes.
Some of us will have a harder time losing fat than others.
Some of us will have a harder time building muscle than others.
Some of us will need to eat more or less than others.
Some of us might feel best with less carbs and more fat, others of us might feel best with more carbs and less fat.
Some of us might feel best eating lots of protein while others of us might feel best eating less protein.
Sure, we’re all similar in many ways – we’ve all got brains, hearts, stomachs, arms, and legs, and we all need protein, fatty acids, vitamins, and minerals – but the specifics of how we might need to eat, move, and live in order to thrive might vary greatly.
We’re each unique, and will need to do the best with the genetic, epigenetic, and microbiotic cards we’ve been dealt.
Any diet or exercise program should serve as a starting point, and if it doesn’t work that doesn’t mean you aren’t trying hard enough or that you’re broken, it just means that you might nor be taking the right steps in the context of your unique circumstances.
You’ve got the power to shape a healthy, strong, capable body, but it will take some fine-tuning and experimentation to figure out what works best for you, and much of this process will be trial and error.
So take action, but don’t get married to any particular process or strategy.
Assess your progress.
Rinse and repeat.
Just don’t quit.
You’ve got this.