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5 Reasons Why Diets Don't Usually Work

You've been there so many times. You've decided that this time "THIS IS GOING TO WORK" and you are determined to make this new diet stick. You promise yourself that "THIS TIME THINGS WILL BE DIFFERENT", you are committed to putting in more effort, to having more willpower and to making this work... and yet, a few weeks (or maybe months) later, you find yourself back at square one. You've decided that the diet you tried was not the right one, you've fallen off the wagon and are promising yourself to start a new diet on Monday.

Research shows that no matter what diet you try (low carb, low fat, Paleo or Keto etc), whilst you may initially notice some weight loss on the diet, you will likely reagin this weight within one year. The problem with diets is that they are very difficult to sustain. All it takes is for someone to bring in some cake to work, for you to feel down one day or for you to drink a bit too much and fancy some carbs the next day, for the diet to be over very quickly. All diets will allow you to lose weight in the short-term but here are 5 reasons why diets don't usually work long-term:

1.Willpower fatigue

One of the main reasons that diets eventually fail is that willpower will only carry us so far. You have probably experienced that feeling of having gone through a long and stressful day, coming home tired and thinking "I just can't be bothered with this diet today, let me just eat what I want to". We only have a certain capacity to make decisions throughout the day. Once we use up our decision making capacity, we are much more likely to fall into old patterns of behaviour. Also, diets tend to be very strict and require you to stick to a lot of rules around what you can and can't eat. Whilst these rules may seem manageable initially, eventually you may feel as though these rules are just holding you back.

2. They don't resolve the underlying drivers for your eating habits

Most people know what they should be eating to have a healthy diet. Where someone has gained weight, the issue isn't usually a lack of knowledge about what to eat. This is why diets and meal plans can be unhelpful. All they tend to do is to prescribe some more rules and give some more information around what to eat and what not to eat. Instead, for many people, they are over-eating because food is something that they turn to as a coping mechanisms when they are stressed/tired/anxious/lonely/bored. For others, their food choices are directly connected to their relationship with alcohol and they find themselves eating more once they've had a few drinks. For some, food is the only treat they have to look forward to at the end of a long day. Other people may turn to certain foods out of habit and just find themselves eating the same unhelpful things day in and day out. There are many drivers for food choices beyond just eating to fuel our bodies or beyond just eating for the taste of the food. Without finding and resolving the underlying drivers of food choices, it can be very difficult to change your relationship with food long term.

3. A lot of people looking to lose weight may actually be struggling with disordered eating

Many people that are looking to lose weight through a diet, may actually be struggling with binge eating disorder or bulimia. Binge eating is a pattern of behaviour that involves eating a lot of food in one go and feeling uncomfortably full afterwards. It usually comes with feelings of guilt and is a behaviour that someone engages in when they are alone. If someone is struggling with binge eating or bulimia, diets can actually just make the binge eating much worse and in the long-term lead to more weight gain. Binge eating requires psychological treatment and not just another meal plan.

4. They are too rigid and inflexible

Diets are very restrictive and they often don't give you the permission to be spontaneous. You have to say NO to that birthday cake, you have to say NO to going to that restaurant and you have to say NO to eating the meal your partner has cooked for you. Eventually all of these rules and the restriction they place on you can become too much and you decide to just give it all up. The issue with food rules is that as humans we tend to be very all-or-nothing about any type of rule. So we are either "following all of the rules" and being GOOD or we are "following none of the rules" and being BAD. This can be a very unhelpful mindset to get into as it doesn't allow us to have a balanced and flexible approach to food.

5. Our body adjusts to what we are eating

Often your goal in going on a diet would be to lose weight and then to go back to eating "normally" again. A lot of people don't go into a diet thinking that this is they way they will eat for the rest of their lives. They don't imagine that they are giving up cake/pizza/beer etc. forever. The problem with this however is that, our bodies get used to the new foods we are feeding them. We are able to lose weight and sustain it because we are sticking to this very low calorie plan or just eating this very limited range of foods. If however, we go back to eating "normally" again and start introducing other foods, the weight will just start to come back on again. Diets also don't allow you to connect to and work with your body. You are relying on food rules to control your food intake rather than working with your body's natural signals and cues. Long-term diets can be difficult to maintain because you can't always be in complete control of what you are eating e.g. in restaurants or when on holiday.

If you've struggled with diets in the past, know that this isn't your fault. Diets are designed to fail. Whilst they may work short-term (unless you plan to rigidly stick to the diet forever), long-term they don't tend to work for sustained weight loss. A much more helpful approach to losing weight and keeping it off long-term is to understand and resolve the underlying drivers for your unhelpful food behaviours. If you can then gently build some new habits around food and your lifestyle more broadly, this will allow you to improve your health (and lose weight) without feeling miserable and deprived. If you would like some support to lose weight and shift your relationship with food, get in touch with us at to book in a free consultation.

"I tried every diet in the book. I tried some that weren't in the book. I tried eating the book. It tasted better than most of the diets" - Dolly Parton


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