Diets Don’t Fail

I have written a lot about weight loss. Mostly because it’s the number one topic that people want to talk to me about when they’re discussing their health and fitness goals. Also, because I have experienced serious weight loss myself. And last but not least, because there is so much AWFUL and outright wrong information out there. Every fit-fluencer with an instagram account and/or youtube channel seems to spread more nonsense than ever. 

As human beings we are very susceptible to believe people who say what we want to hear. It’s called confirmation bias. When you google a question, you tend to find the answer you want to hear. For example, if you want to lose weight, but you don’t want to count calories, you google for arguments why it is not necessary to count calories to lose weight. And if you find someone who is looking ripped and pretty or handsome and fit and healthy who tells you that you don’t need to count calories to lose weight, you believe them. You may also  end up buying some product that the fit and healthy looking person is peddling while all you have to do is follow along their five minute workout. Because apparently that is all it takes. Youtube is full of videos with nonsense like that. Unfortunately, just because someone looks fit and healthy doesn’t mean that they can help you look like that and it also doesn’t mean that what they say is true or applicable to you. The reality is that there is:

a) no single product that will shed the fat, 

b) there is no single exercise or programme that is miraculously better than the rest and 

c) there is no quick fix.

The truth is that any (calorie restricted) diet can work for anyone. I personally have lost weight on a low fat high carbohydrate vegan diet, a high protein, low carb diet and everything in between. A diet is just much easier to adhere to if it fits the dieters preferences – for example a ketogenic diet is difficult for a vegan, or intermittent fasting is difficult for someone who likes snacking all day. But at the end of the day, if you consume less calories than you expend, you lose weight – preferably fat and not muscle – and research proves that every time. I am not aware of any study where people were put on a one way or another calorie restricted diet and did not lose weight.

You may argue that you have been on a diet and it didn’t work for you. And that may be true – but you just consumed too many calories on it, i.e. you were not in a caloric deficit consistently enough. I have previously blogged about why scale weight is not necessarily the best indicator for a diet’s success as most of us strive for body recomposition – i.e. lose fat and gain muscle. Nobody wants to lose muscle on a diet and maintain or even gain fat. I would consider a diet a success if you lose body-fat on it. That’s the problem with a lot of crash diets or “weekend cleanses” or “3-day-body-reset” diets – you lose a couple (or even more) pounds of water weight (and even worse, potentially muscle), which you instantly gain back once you start eating proper food again. But you don’t really lose a significant (if any) amount of body-fat in such a short time.

Most people misjudge the amount of calories they eat. In our world of supersize everything this is no surprise. Numerous studies have shown that people under-report calories they consume. This ranges from 18% to 54%, but can reach 70%.¹ Nearly everyone tends to underestimate calorie intake, but there is evidence that the higher someone sits on the BMI (body mass index, which measures weight in relation to one’s height) the more likely calorie consumption is under-reported. There are several reasons underlying this, some of which are intentional and some aren’t, but it’s quite clear that if a diet doesn’t “work”, it most likely relates to measuring caloric intake. 

Notwithstanding the above, if you have underlying health issues this may influence how you respond to a diet. For example, as I have previously written about, ketogenic diets and intermittent fasting work well for a lot of people who struggle with blood sugar control, cravings and energy levels, insulin sensitivity and inflammation. Intermittent fasting is a great tool to lower calorie intake as many people respond well to limiting their food intake to a few hours in a day.

Diets don’t fail if you consume less calories than you spend. The reason why people say that diets fail is not that they don’t lose weight (preferably fat) on a diet, it’s that THEY CAN’T KEEP THE WEIGHT OFF. The famous biggest loser study gets quoted a lot as a proof that diets don’t work (see my blog on fasting).² But obviously they do work – these contestants lose a huge amount of weight in a short period of time. Many of us have lost weight when we were on a diet and restricted our calories in one way or another. The problem is that we end up gaining it back – and then some. A study with over 14,000 overweight and obese participants showed that less than one fifth of individuals who achieve a 10% reduction in body weight successfully, maintain that weight loss after one year.³

In the case of the biggest loser contestants, I think the main reason why they gain all the weight back is because the show doesn’t teach new habits. These people go back into their “old” environment – their jobs, family, neighbourhood and the lifestyle that comes with it. But they haven’t learnt how to embed exercising and dietary changes in their old environment. The contestants were simply taken to an “outside” artificial environment where their diet was tightly controlled and all they could do was exercise for eight hours a day. But they don’t learn how to incorporate better food choices in their everyday life. They don’t create a habit of going to the gym before or after work or picking up tennis lessons at the local community centre on the weekend. They don’t learn how to order the healthy dishes at the restaurant. They haven’t abandoned the habit of snacking in front of TV on their sofa with their spouse. 

As I have explained in my previous blog, the key to a healthy and fit lifestyle is to create small habits that make a big difference – and that can include keeping weight off after a successful diet. Research has confirmed that implementing and maintaining a regular exercise regimen is an effective strategy for weight loss maintenance.³ Exercise is more important to keep the weight off than as a tool to lose weight (using exercise as a means to lose weight can be quite inefficient as I have explained here). If you exercise regularly, you start identifying yourself as a healthy and fit individual, and this image of yourself is reflected in all the choices you make on a daily basis. If you see yourself as a fit and healthy person, you probably buy less processed foods at the supermarket, you may have less desserts in your fridge, you are more likely to order a salad in a restaurant. 

Keeping the weight off means you have to make changes to your lifestyle. You can’t diet down and then go back to your old way of eating (and drinking) and expect to keep the weight off. Establishing habits that support a healthy lifestyle is essential. That’s why it is so important to adopt a diet that is sustainable for life. We learn what and how to eat for optimal health and we learn to establish habits that support this. For example, we can replace our snacking in front of the TV habit with a walk outside and a cup of tea. Instead of a muffin we may have a piece of fruit with our morning coffee. Instead of having a weekend dinner at the all you can eat buffet we may go to a steakhouse. We can only be successful in keeping the weight off by changing the environment, the triggers that make us eat, establishing habits that support energy expenditure. Fill your life with activities that make you happy. Don’t go to the gym if you hate lifting weights – you won’t keep it up. Do you enjoy swimming? Hiking? Playing tennis? Cycling around the park? Needless to say, the benefits of exercise go way beyond weight loss maintenance.

For most people, a diet (as in lowering calories to lose weight) is very doable and successful if done right. The problem is to find a diet that you can sustain for life – as in a healthy way of eating for life that allows you to stay at the weight you’re comfortable at and supports maximum health. To lead a healthy and fit life you need to have the habits that support that – and not fight it. As such, the goal shouldn’t be to lose weight on a diet. The goal should be to establish healthy habits. As I have written before, a healthy body takes care of the weight by itself. 

Keeping weight off requires long-term behaviour changes. You may even have done so successfully in your life in another area, e.g. quit smoking, quit drinking, start exercising regularly. The additional challenge when it comes to healthy eating habits is that we can’t avoid food. When you stop drinking, you don’t keep alcohol in the house and you don’t go to a bar. When you stop smoking you don’t buy cigarettes and may stop seeing your chain smoking friends. But when it comes to food, we’re constantly bombarded with it – we cannot avoid it. And we need to eat, we can’t just stop, we still need to shop groceries and go out for dinner with family and friends. Habits like not keeping trigger food in the house, not shopping hungry and not going to the all you can eat buffet can help here.

Diets are the easy part. Anyone can lose weight on a calorie deficit diet. Keeping the weight off is where it gets difficult and where behaviour changes and habits are the key factors for success. Weight loss is not the goal. The goal is the process that builds and embeds new healthy habits in both diet and exercise.

¹ Wehling H., Lusher J. (2019). ‘People with a body mass index ⩾30 under-report their dietary intake: A systematic review’, Journal of Health Psychology 24(14), pp. 2042–2059

² Fothergill E. et al (2016). ‘Persistent metabolic adaptation 6 years after “The Biggest Loser” competition’, Obesity Research Journal 24(8), pp. 1612-1619

³ Kraschnewsky J.L. et al (2010). ‘Long-term weight maintenance in the United States’, International Journal of Obesity 34, pp. 1644-1654

⁴ Some research has actually questioned this long held belief of exercise as a weight loss maintenance strategy. There is a lack of evidence from randomized controlled trials to support this hypothesis. However, there is considerable evidence that support it, primarily from observational and correlative studies. For further reference, I recommend this article:

Foright R.M. et al (2018). ‘Is regular exercise an effective strategy for weight loss maintenance?’,  Physiology and Behavior 188, pp. 86-93