Please Please Please! Stop crash dieting!
Did you know that 85% of overweight people will have absolutely no problem at all losing weight in their life. That’s promising news. Amongst the squillions of diets out there, we can safely say that they work pretty well. But not so fast! 80% of these people will gain back most, if not all of what they lost within a year. Within 2 years this number goes up to 85%. Far out! But it gets worse. Give it another year – that’s 3 years after initial weight loss – 95% of all people who successfully lose weight, gain it all back again.
What the heck is going on? In this article we’re going to discuss why we’re so good at losing weight, but absolutely suck at keeping it off. And it’s not even our fault. Well in some way it is, but not the way we’re thinking. Being lazy. Running out of willpower. Not having what it takes. There’s more to the story.
Please please please stop with the aggressive crash diets! This is my incessant plea.
When we take a purposeful, aggressive approach to losing weight our body will very predictably fight back. This is counterintuitive when we know the health consequences of overweight & obesity – such as diabetes, heart disease and cancer. Why then would our body’s naturally resist losing the weight? The answer – We’re designed to.
The Weight Loss Defence Mechanism
We currently possess the exact same genes that our ancestors possessed hundreds of thousands of years ago. The way our brains work and our cells metabolize are no different from our prehistoric ancestors. What does this matter? Well, were a bag of old genes functioning in a very modern world. Our genes adapted to “feast or famine”, and we now live in a world of serious food abundance. This food abundance has only really been a thing for the past century or so.
This is where the weight loss defence mechanism comes in. When it comes to survival, our bodies have been designed over roughly 200,000 years to do the following:
- Defend excessive weight loss in the attempt to avoid starving to death – The ever so common weight loss plateau.
- Restore weight to prepare for the next famine, once enough energy (calories) is available – When a crash diet ends and/or dieter binges from frustration.
- Prevent weight loss from happening in the future, because we just can’t be too careful – Sending many into a mad scurry to try the next diet or product.
Ironically, we have a deeply ingrained mechanism that fights us to lose weight – due to a lack of understanding of this mechanism (until now), we just fight it right back – and of course, never willing to back down (with nothing but our survival in mind) it fights back again with even more ferocity – and so on we go further into the downward spiral of yoyo dieting.
The “magic” number 1200
For some reason in weight loss circles, 1200 seems to be the “magic” number. To lose weight, cut all calorie intake down to 1200 calories per day. Please let it be on the record that I did not say these words, and I do NOT encourage this. It’s just what became common “knowledge” somehow. This is an incredibly rapid drop in calories. Far too rapid in fact.
To put it in context, a female of 5ft5” and 150lb who doesn’t exercise needs to consume roughly 1430 calories just to exist. This is the absolute minimum daily energy intake required to keep heart pumping and brain firing (otherwise known as basal metabolic rate).
Whether it’s 1200 or another number radically lower than your current calorie intake, how is our inner defence system going to react? “FAMINE!”. “Emergency! I’m gonna die. Quick do something – ANYTHING – to not let me die!”
There’s a very well accepted theory in weight loss science called the Set Point Theory. It states that each person has a set weight and/or fat percentage that our body is pretty happy at. When we’ve been at a certain weight for many years, our body adapts and decides it’s where it want’s to stay. Sudden and drastic changes in caloric intake, followed by rapid shrinking of fat cells can trigger the weight loss defence mechanism. It’ll do anything to bring us back to the Set Point.
This response won’t necessarily be immediate the morning after calorie restriction, for example, but when we start to see that typical plateau during crash diets, the weight loss defence system is surely starting to rear it’s ugly head. Over the past few weeks or months, our prehistoric brain gotten a little more concerned about the energy shortage, and because it’s got no idea there’s a Wendy’s around the corner, it starts unleashing it’s resistance plan.
What is the resistance plan? Let’s touch on the above points in more detail –
Defending weight loss
Firstly it down regulates any “unnecessary” energy expenditure to defend us from starvation. We can’t afford any waste. Small movements like twitching and shuffling – which are actually very normal – get eliminated. We even start to blink slower. Energy required for digestion is compromised as well as the energy used for muscle maintenance or building. This is all in an attempt to keep the lights on – in the brain. It’s inevitable though that certain areas of the brain, namely the cerebral cortex, which is responsible for calculation and logical thought, are down-regulated because they’re not absolutely vital to our survival.
So you’re a little sluggish, a little bloated and just a little dumber. Maybe you can live with that, as long as you’re losing weight. But these are all calorie burning functions that are eliminated to preserve calorie expenditure. If you’ve made the desperate attempt to cut 1000 calories per day, after some initial weight loss, the defence system will match that by turning down the output. Therefore the calorie deficit you started with is no longer a calorie deficit. We’re just left with a sub-optimal human being. The only choice now to lose more weight is to cut calories even further…until the defence mechanism catches up again.
Restoring the lost weight
Once a crash diet comes to an end and you celebrate with spare ribs and beer, you’re not the only one having a good time. Our defence system is having a fiesta too. In order to restore the extreme calorie deficit that’s been going on for too long now, it’ll hold on to these precious calories for dear life. Where one person who creates modest calorie reduction might experience a small weight gain after holiday season, someone who threatens the ancient defence mechanism with extreme dieting can see 10, 15 even 20 pounds stack right back on in no time. We all know someone who’s taken a little vacation and come back with everything they’ve enjoyed around their waste. Maybe you’ve experienced it yourself. This is your body rebounding to restore the weight that you lost incase another food shortage comes back around soon. An aggressive weight loss approach begets an aggressive rebound.
Preventing future weight loss
Once returning back to the regular rhythm of life and the heartbreak of regain has passed, it’s time to get back to “the diet”. Back to the “killer workouts”. However, now the hard work that you put in reaps much less reward. The weight loss defence system, just doing what it does to keep us from dying, makes weight loss even more difficult. Remember to our ancient brain, fat stores are just energy and it’s preventing further depletion at all costs.
The defensive hormones
It’s believed that our body tries to defend, restore and prevent weight loss largely through the hormones Leptin and Ghreline. These are 2 opposing appetite hormones, not to be messed with. Leptin is secreted by fat cells (adipocytes) to tell the brain that there’s sufficient energy available, and therefore, no need to sound the hunger sirens. As fat cells shrink during weight loss, Leptin secretion is reduced, and Ghreline secretion is increased to kick start hunger sensations. These hormones are powerful, and are said to control our behaviour more than we think. It’s time that we stopped betting on willpower to out wrestle our biology.
There’s absolutely no doubt that certain foods are more addictive than others. Many factors influence our cravings for certain foods, one of the big ones being the dopamine explosion in the brain from highly palatable fatty, salty and sugary foods. This is one thing, but many of us don’t recognize that our weight loss defence system is steering us towards these foods as well. If the ultimate goal is to get calories into the body as fast as possible, to make up the aggressive calorie restriction, high calorie dense foods are the target. French fries, cheese, white bread, nutella, pizza, oils. The foods that offer higher calories for a relatively low volume. The lower the volume, the more calories we can pack in.
Why do we go on food binges? Why do we become obsessed with food while dieting? Yes, one part of it is psychological. We all want what we can’t have. The other (very big) part is biological. Our genes are still set up for famine – the rebound of calorie restriction pulls us with monumental force toward the next available source of calories – and here’s the kicker, there’s absolutely no shortage of calories in our current environment.
The serious risk of weight cycling
Weight cycling is the term given to yo-yo dieting. We restrict calories – we lose weight – metabolism slows down – weight loss plateaus – we regain the weight (sometimes more) – the cycle continues.
A study published in the International Journal of Obesity showed that the more often someone dieted, the more overweight they were likely to become after long term follow up. This is because the biological defence mechanisms we’ve discussed above fights back even more fiercely every time a new cycle begins. At each new cycle, the ability to lose weight becomes harder, and the rate at which we put it back on is increased. Another research published in Obesity Reviews showed that there’s a potential for fat cells to increase in number (not just size) during the post diet phase, in an attempt to hold on to as much energy (fat) as possible, before another possible period of famine.
Permanent metabolism damage
Then there’s the risk of permanently blunting metabolism on the long term, rendering weight loss virtually impossible. You may remember the story that circled the media back in 2016 about The Biggest Loser tv show.Contestants experienced a giant slowing of resting metabolic rate for at least 6 years after the show ended. This influenced a huge amount of weight regain, despite their best efforts to maintain what they’d lost.
The main study that sparked this media interest was allegedly the longest follow up study of metabolic change in relation to weight loss. They found that metabolism of the contestants reduced by over 26% more than what it should have, in comparison to actual weight lost…AND that the contestants with the greatest weight loss over the 30 week program had the greatest reduction in resting metabolic rate upon long term follow up. The Biggest Loser was indeed an extreme case, but right now as we speak, there are many people causing potential long term damage to their metabolism, weight loss goals and overall health.
Hopefully after reading this, the sustainable approach to weight loss suddenly looks much sexier. In our culture today we tend to believe nothing’s worth having unless we really work for it. Sacrifice. All or nothing. Social media is littered with sensational diets, workouts and philosophies that constantly make us second guess ourselves. As far as weight loss goes, keeping it simple and sustainable will always reap the best long term results.
Please please please stop with the aggressive crash diets!