a 5-minute read
Have you heard people say that being overweight is a choice? Or that it’s just about calories in versus calories out? Well, misinformed statements like this are often said by those with little understanding or recognition of the complex and multifactorial nature of obesity and are just… big fat lies!
As someone who has struggled with my own weight from a young age and who was bullied for being the ‘fat kid’, I’ve had a personal interest in weight management for as long as I can remember. In fact, I think it’s one of the reasons why I entered healthcare and why I’m such a strong advocate for exercise, having found it to be the best way to control my own weight after trying and failing many other methods.
Although exercise has, and still does help me manage my own weight I know it’s not the answer for everyone, and I have slowly come to understand that weight management is a complex and complicated topic that goes far beyond just exercise and calories. Unfortunately, many healthcare and fitness professionals have not and many still believe that being overweight is a simple condition brought on by choosing to eat too much and exercise too little.
Calories In / Calories Out
This is bullshit, in fact, if I hear another fitness professional say ‘calories in v’s calories out’ without any context I think I will drop kick them in their fart box, because although in principle this sounds accurate and simple, it’s just not this simple or accurate. The causes of weight gain and obesity are in fact far more complex than just ‘calories in calories out’ involving physiology, psychology, and sociology.
Saying obesity is as simple as calories in versus calories out is no different than saying poverty is as simple as money in versus money out, or depression is simply happiness in versus sadness out! I think we can all agree that no-one chooses to be depressed or poor so why is it any different for obesity?
In the late 1990s, obesity was classed by the World Health Organisation as a global pandemic due to the direct links it has to increases in many other diseases such as diabetes, hypertension, cardiovascular disease, osteoarthritis, some forms of cancer, and mental health issues such as depression (ref).
There is still much debate around if obesity should be considered a ‘disease’. But when you consider a disease is defined as…
- A condition that impairs function and reduces life expectancy
- A condition that leaves an individual more susceptible to other diseases
- A genetic impairment that leads to other functional impairment
Obesity checks all of these, even the last one! Yes obesity is a genetic impairment. There is now some strong evidence that shows obesity is dictated a lot by genetic factors as demonstrated in multiple identical twin studies, done in multiple countries, on various different aged individuals (ref).
It is also known that genetic variations can increase an individuals propensity to obesity such as leptin and POM-C receptor deficiencies (ref, ref). Our genes play an important role in how we all respond differently to the foods we eat, the number of calories we consume, and the environments we consume them in.
For example, have you ever wondered why two people who eating the same types and amounts of food often have completely different weights and body fat percentages? Well an interesting study conducted on 12 pairs of identical twins closely monitored the affects of overfeeding them by 1000 calories a day, everyday, for 100 days, and found weight gains were very similar for each twin, but varied hugely between the pairs of twins from 4kg to 13kg (ref).
This clearly shows how genetics has a role in determining how much weight is gained based on the calories consumed. There have also been a number of studies that looked into the effects of genetics on weight gain in rats to try and see if they could find any more answers.
In one study 100 rats were all fed the same high-calorie diet for a few months. Again they got a lot of variation in amounts of weight gained by the rats, with a bell shape curve with a few of the rats not putting on any weight at all, a few rats putting on huge amounts of weight, and most of the other rats falling somewhere in between (ref).
Now the interesting part with this study is they then took the rats from this trial who didn’t put on any weight and bred them together, as well as taking the rats who put on the most weight in the trial and bred them together. And after a few rounds of breeding these different weight gaining rats they got two very different types of rat.
In the first group of rats they got offspring who were very diet-resistant, that is rats whose weight did NOT increase when they over-consumed calories. However, in the other group of rats they got obesity-prone offspring who gained weight very quickly and very easily with overconsumption of calories.
What’s also interesting is that if you take these obesity-prone rats and place them on a low-calorie diet they lost weight, but as soon as their calories were returned back to normal baseline amount their weight quickly returned back to their starting obese weight, even though they were not over consuming calories. Meaning you can get an obese prone rat to lose weight, but unless you keep it on low calories forever its inherent nature is to be an obese rat.
The same thing most likely applies to humans. If you were to take a thousand children and weigh them, their weight will also be distributed in a bell-shaped curve. Some skinny kids, some kids in the middle, and some overweight kids. Some of the skinny kids will remain skinny throughout their life, and some of the obese kids will stay obese throughout life, meaning you could argue that their weight, to some degree, is predetermined.
Now, of course, it’s not just this simple as humans have had the same genes for 100’s if not 1000’s of years, and it’s only recently that obesity has become a bigger problem, so how do we explain this? Well, the obvious answer is the sudden increase in the easy access to very calorie-rich food.
It is now extremely easy to eat your entire daily quota of calories in a single meal that doesn’t cost much and doesn’t leave you satisfied for long. High-calorific meals full of calories dense corn starches and sugars, not to mention sugary drinks and alcohol that can contain 100’s if not 1000’s of calories without providing much satiety mean we over-consume really easily.
Although our genes play a big role in our weight, our environment also plays a huge role too. The readily available abundance of calories in many modern lifestyles is a relatively ‘new thing’ in human evolution, and it appears our genes haven’t quite managed to adapt and it’s not certain if they ever will.
In our history, genetic selection has prepared and equipped us much better for famine rather than feast, and for good reason. Food used to be scarce and infrequent, and periods of starvation were common throughout human history. Obviously, this was difficult and unpleasant to deal with, but is the opposite scenario we now face any better?
So if obesity is a disease the question we need to ask, just like we would for any other disease, is how can we prevent, treat, or even cure it? Well just like any complex disease there will not be any one single simple quick fix or solution. However, one interesting area that could hold a lot of potential is how our neurophysiology can affect our behaviour.
A neurotransmitter called GLP-1 has been shown to affect nerve cells that control whether we feel full or not, and so dictate if we eat or not, and GLP-1 has been found in both our brains and our guts literally allowing them to ‘speak’ to each other (ref). Research has shown that if you increase levels of GLP-1 your desire to eat is significantly reduced and even halted, acting a bit like the full signal on your cars fuel tank and although more work is needed there are some promising results here (ref)
Of course, GLP-1 or any one neurotransmitter in isolation is not the whole answer to obesity and there are numerous other avenues of research into physiology, psychology, and behaviour change needed, not to mention a huge shift in governmental and societal approaches and beliefs to food and weight management. However, research like this does give us some insight into the complexity of obesity and some hope that there are solutions for this growing pandemic.
Moving forward we all have to recognise that if anyone wants to loose some weight they often have to change their behaviour but also their environment to do this, which isn’t always easy or possible to do. However, if we want to change a populations weight then its essential that we all change the environment so that it is suitable and conducive to weight lose for everyone, and not just for those in privilege!
Lose some weight, lose some pain
Personally I think a lot more healthcare and fitness professionals need to be much better educated into the complexity of obesity, and far better educated and equipped to help and support those with it. A recent paper has highlighted how obesity is highly prevalent in chronic pain populations, and as a physio, I have found helping some people lose some weight can be a great way to help them lose some pain (ref).
Not only does losing weight decrease some of the physical and mechanical loads on our bodies which may be sensitive or irritated, but it can also, and probably more so, help to lower systematic inflammation levels and improve a host of other metabolic and neuroimmune functions.
More importantly, I think helping someone in chronic pain lose some weight by helping them find some strategies that work for them in their current situation, can help improve their confidence and self-efficacy which can in turn, help them gain control and ownership over many other aspects of their lives which may help mediate their pain.
Again, I am not going to say this is simple or easy to do, but from my own personal experience I know how much better I felt once I gained control over my own weight, and I think many others will do too.
As always, thanks for reading