Diets Don’t Work – Here’s Why

It’s that time of year again – one minute, you’re opening a mini chocolate box every morning, buying three courses of pancakes and pretzels from a German market and inhaling every pig in blanket you can get your mitts on. The next, you’re being bombarded with advertisements of women pinching at their love handles, wrestling with their jeans and telling you that a new meal plan will be the one to make you slim down for good.

Many of us feel guilty about our festive indulgence, and use the New Year as a chance to forget all the things we ate. Dieting isn’t just for post-Christmas though – this process can last a lifetime. Apparently, the average woman spends around 31 years of her life on a diet, with around one in five women reporting that they are “often” or “always” following a diet.

Given the literal years of practice, you think we’d all be pretty good at dieting by now. But if they worked, women would need to follow them for decades. We wouldn’t vow to lose weight every January 1st, we wouldn’t need to try multitudes of different methods or spend a collective $168.95 billion on the diet industry. We would lose the weight and move on. It’s clear to see that this isn’t the case for most of us, and the statistic that 95% of diets fail is enough to set off alarm bells. So if you’re considering cutting your food intake to lose weight, let me tell you why you shouldn’t.

(I’ll also add that many plans that tell you to change your eating habits will sometimes masquerade as “lifestyle changes” to avoid being grouped into the 95%. Here’s a rule for spotting the sneaky ones: if it promises you weight loss, it’s a diet.)

Doesn’t dieting cause weight loss?

Yes – in the short term. Weight loss usually sticks around long enough to get a smiling “after” photo, and the diet industry uses this short term success to make us continue to buy into regimes despite their awful track record. And we listen, because it’s losing the weight that’s the hard part – keeping it off is easy, right?

Well, the long term success of dieting is a different story altogether. Research by Traci Mann compiled every study that she and her student could find on diets that included a 2+ year follow up.  It was found that in the first year, dieters lost weight, However, in the years that followed, people returned to being an average of 2.1lbs below their starting weight. In contrast, the research found that non-dieters gained an average of 1.2lbs over this time – a negligible amount to say the least. Imagine if you were presented with the idea that you could live a life of satiety, never count a calorie, order whatever you like at the restaurant and get dessert too. Or you could restrict your meals, resent your lunchtime salad and resent yourself every time you think about biscuits, and still end up being near enough the same weight. Pass me the custard creams.

Another study followed people in Finland over a ten year period. Two key predictors of weight gain were found – dieting and irregular eating. People in this study generally gained weight over the decade, but those who dieted had an accelerated level of weight gain. Dieting led to people GAINING more weight than not dieting at all. If that’s not a reason to delete MyFitnessPal I don’t know what is.

Falling off the wagon

So why doesn’t the fact that so many people have regained all the weight they lost, tried EVERY diet under the sun or rejoined Slimming World for the fifth time make us question the effectiveness of dieting? Because we believe it’s our fault – we fell of the wagon, we slipped back into our old habits, we’re the ones who failed.

In a way we are to blame. But it’s less of a choice and more a biological mechanism. Firstly, dieting causes a preoccupation with food. Have you ever realised that when you’re dieting, eating is all you can think about. Cut out carbs and suddenly you can locate every bakery in a 10 mile radius? Food restriction actually makes food taste and smell better – it’s your body telling you to EAT.

Eventually we give into our urges and eat every ‘bad’ food that we can sniff out with our heightened sense of smell. Usually when this happens, people blame their lack of willpower and vow to restrict again, even harder, next time. This only perpetuates the cycle of restricting and binging. Christy Harrison explains this as a pendulum – dieting tells our body that food is scarce, so when we see food our body swings into action, encouraging us to eat as much as we can when we have the opportunity. It’s a survival mechanism that allows us to find food in times of famine. As long as we keep swaying towards restriction, our bodies will pull us towards binging. The only way to still the pendulum is to let it settle in the middle, to listen to your body’s hunger and fullness cues and act accordingly. Any attempt to stifle them only makes them louder.

As well as this initial response, our bodies go through long term biological changes. Losing weight slows our metabolism, meaning that we burn less energy and so need to consistently eat less to maintain the lower weight. An extreme example of this occurred in contestants from The Biggest Loser. All of the contestants metabolisms slowed down and were still much lower than average six years after the finale. One former contestant, even after regaining nearly half of the weight he lost, was burning 800 calories less per day than an average man of the same size. Weight loss also throws the balance of hormones that signal hunger and fullness, and a follow up found that these rates are not fully restored one year later. This means the more weight we lose, the harder it is for our body to regulate our appetite and send the message that we are full.

The existence of these mechanisms supports Set Point Theory – the concept that our bodies have a certain weight range at which they function best and will fight to stay within this range. Although there is no way to measure a person’s set point weight, this theory will ring true with the vast majority of dieters who keep returning to their starting weight, no matter much time, effort and willpower they invest. The good news is that this theory also explains why non-dieters seem to have a fairly stable weight over time – our bodies  know what they’re doing, and left to their own devices they will work to account for any over- or under-indulgence.

Set up to fail

So why is dieting made to seem so simple and effective, when the reality is the total opposite? Because this keeps us coming back for more. The diet industry chips away at our self esteem and makes billions from us blaming ourselves when we fail – all we had to do was eat less, but we couldn’t even do that. Feeling inferior, we return to the dieting game ready to prove that we can succeed, we can starve and we can shrink. Rinse and repeat. We don’t realise that the outcome we’re seeking is almost impossible.

So if you’re thinking about starting the new year with a diet, I urge you to reconsider. The diet industry might tell you otherwise, but the research is there – restricting food intake does not help you lose weight in the long run, but it is likely to confuse your body, make you hungrier, mess up your metabolism and cause you to gain more weight. You cannot fool your body, you cannot out-will biology.

The best thing you can do for your body this year is challenge dieting’s ‘forbidden fruit’ mindset. Refusing yourself food only makes you it more, and can make you feel out of control when you finally eat. When you lose the guilt – meaning any ‘bad’ foods are just foods – you’ll be able to make better judgements about what you actually WANT to eat. Sometimes it’ll be an apple. Sometimes it’ll be a pizza. It’ll probably never be a rice cake. Eat whatever you like, and then move on to doing literally anything that are more important than being preoccupied about food. And most importantly, care for your body – it’s much more incredible than you think.

(Photo by Brooke Lark on Unsplash)

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