5 Reasons Why Diets Fail

Only a very small percentage of people that start a..

5 Reasons Why Diets Fail

5 Reasons Why Diets Fail

Only a very small percentage of people that start a diet will actually finish it and get the results they want.

You can greatly increase your odds of being one of the successful people by simply understanding why diets fail, and then taking action to work around these problems.

The following are my top 5 reasons why diets fail.

Lack of Willpower

We live in an age of instant gratification – movies on demand, shopping at the click of a button, and microwave meals zapped and on your plate in three minutes flat.

So it would seem that the prevailing mindset is that if I want that bar of chocolate, I want it now, and why shouldn’t I have it?

I can give you 100 reasons why not, starting with those love handles that sit so attractively over your belt on the back of your hips, but I am not going to be there when you’re staring at the candy counter in the petrol station.

You have to want to make a difference to yourself because in the final analysis, it’s down to you and nobody else.

It takes discipline and strength of character to effect a fundamental change in any of our ingrained habits, but once the momentum has been created, and the sense of satisfaction and well-being becomes your constant companion, you can do it.

Not Knowing How Much You Are Eating

Knowing how much you are eating is the most important factor for dieting success. When I say how much you are eating, I’m talking about calories, not the volume of food.

The number of calories you consume will determine the changes you see in your physique (or lack of).

To control our body composition, we must understand the energy balance equation. Energy balance is the sum of calories in vs. calories out.

  • Calories In = The calories we consume (and absorb) through our diet.
  • Calories Out = The calories we burn through our basal metabolic rate (normal body function), thermic effect of feeding (digestion and processing of nutrients), thermic effect of activity (formal exercise), and non-exercise activity thermogenesis (subconscious movement).


Energy balance dictates body weight change based on the first law of thermodynamics, which states energy cannot be created or destroyed.

When you consume more calories (energy) than your body needs, you gain weight.

If you consume fewer calories than your body needs, you lose weight.

To know exactly how much you are eating, you need to track your diet. If you don’t know how many calories you are consuming, how do you expect to make progress?

First, determine how many calories you need to maintain your body weight. To do this, you can use a BMR calculator.

If your goal is to lose fat, subtract 250-500 calories per day from the results. This deficit will theoretically result in 1-2 pounds of weight loss per week.

If your goal is to build muscle, I would only add 200-400 calories per day to be in a slight surplus. Overfeeding doesn’t help you put on muscle quicker and will just put on extra body fat.

Focusing Too Much on Food Choices

You are probably wondering how focusing on food choices can be a mistake?

By focusing too much on food choices, you aren’t taking into account calories and macronutrients. As we discussed earlier, the composition of your diet has one of the biggest impacts on your physique.

Our bodies don’t see specific foods, they see calories, macronutrients, and micro-nutrients. By only focusing on food choices, you can end up eating the wrong amounts for your goals.

People that become hyper-focused on foods can develop an unhealthy relationship with food. It can cause them to label foods as either good or bad, which can be very damaging.

A single food can’t be labeled as good or bad, it must be examined in the context of the whole diet.

Don’t get me wrong, focusing on consuming healthy foods is good but too much of a good thing can be bad.

Your diet will be more sustainable if you aren’t hyper-focused on food choices. Sustainability is one of the most important factors in a diet’s success.

If you can’t stick to the diet, how do you expect it to work?

Be sure to eat an appropriate amount of calories and macronutrients for your goals. Don’t stress too much what foods they are coming from.

Hit your macro-nutrient targets (including fiber) with mostly healthy foods, and you will be okay.

Unrealistic Expectations

A great approach to any client-focused service, be it personal training or any other, is to always undersell and over-deliver.

We all recognise that to do the opposite is to create disappointment and a nagging sense of dissatisfaction.

So why set yourself up for these negative, and disempowering emotions by having expectations that are entirely unrealistic?

You may want a body like Brad Pitt or Oliver Proudlock, or even the athletic curves and moves of a Lara Croft, but let’s get real for a minute.

If you are 50lbs overweight and give yourself five weeks to get ripped abs or tight buns, you are quite simply setting yourself up for failure.

And with failure comes disappointment, derailment, and a gradual (or swift) regression back to your comfort zone of bad habits and easy self-gratification.

Not Having an Exit Strategy

Do you have a plan for when the diet is done, and you reach your goal? If not, you are setting yourself up for failure.

If you go back to your old habits and way of eating, you will go back to your old body. A fat loss diet can’t last forever, and you need a plan for when it’s over.

Weight regain is one of the biggest problems when it comes to dieting success. At the end of a diet, our bodies are primed both mentally and physically to gain fat quickly.

This is our body’s biological response to dieting.

Here’s what one study published in The American Journal of Physiology had to say about a successful diet:

“To be successful in the long term, our strategies for preventing weight regain may need to be just as comprehensive, persistent, and redundant, as the biological adaptations they are attempting to counter.”

As you can see, not having a plan for when your diet is over is a huge mistake. Avoid putting on an excessive amount of body fat by planning ahead.

To prevent excessive fat gain, you should slowly and strategically increase calories (from carbs and fats).

This is a strategy called “reverse dieting,” and it helps get your metabolism back to pre-dieting levels.

Immediately after the diet is over, you should increase calories by roughly 10-15%. This will get you out of a deficit and help you to start feeling normal again. Then, increase calories by 50-150 weekly and watch how your body is responding.

You should be tracking your weight and comparing pictures each week. Continue to add calories until you start consistently gaining weight each week.

Most people are able to increase calories significantly without putting on too much body fat.

So there you have it – my top 5 reasons why diets fail.

I have personally experienced every single one of these, and I’m sharing my thoughts with you so you can learn from my mistakes.

What about you?

Do you have a tip that has helped you stay on the healthy lifestyle track? We would love to hear it.

Daniel Messer, RNutr, CPT

We eat clean, are always motivated and helpout beginners in need. We sell guides on Cutting, Bulking and Muscle Building. Checkout our website!

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