How Most Diets Fail Us (And What to Do About It)

why diets fail

Over the years the cycle was the same.

I’d get inspired to change my body, I’d buy the book or research the strategy, tell some people about it, and then jump head first into changing my life & health forever.

Often, in the first few weeks, I’d actually get results. Good results.

My arch enemy, the number on the scales, would start to shrink. So did my waist, which left my clothes feeling looser and me feeling greater about my new lease on life.

I’d be off to a good start up until the end of the first month or so, sometimes sooner.

Suddenly food choices that weren’t so diet-friendly would sneak their way into my stomach as I’d assure myself it was “just this once”.

Within weeks, if not days, my weight-loss had stalled. My diet would be on hold until further notice and I’d be scratching my head wondering, What went wrong?.

What I started to notice was that my moments of failure were almost always in the context of making a decision around what to eat for a particular meal.


science as to why diets fail

Most diets I’ve found have a comprehensive list of what & what not to eat, right?

And, for the most part, that is extremely helpful.

But, have you ever noticed the times you’re most likely to fall off the wagon of healthy eating are when you don’t know what to eat?

You walk into the food court at your local mall or you’re at dinner with friends and you’re looking at your options – 90% of which don’t fall within your “What to Eat” list. If you haven’t thought about it ahead of time are you more likely to make a poor decision?

One of the worst acts of self-sabotage I experienced was simply trusting my self-control too much & too often.

And that’s what I’ve found most diets do – They give us a list of “good” foods and hope for the best. But unfortunately, when the moment comes to make a decision around what to eat & when to eat it, we often falter under the pressure and cave to the temptation.

I remembered hearing an old adage that says “Failing to plan is planning to fail”. And I’ve found this to be especially true in the world of health & fitness. Every time I failed to plan ahead I was setting myself up for failure.


An Israeli university study followed 1,100 court decisions over the course of a year. Prisoners who came before the Judge early in the day received parole about 70% of the time, while those that came late in the evening had less than a 10% chance at receiving parole.

Why? The studies showed the Judges simply became worn down by a day full of mental work.

They had fallen victim to something every person who wants to eat well needs to know about: Decision Fatigue.

“Making decisions uses the very same willpower that you use to say no to doughnuts, drugs, or illicit sex,” says Roy F Baumeister, co-author of Willpower: Rediscover the Greatest Human Strength.

Think of your pool of decision-making energy as a finite reservoir: As you make decisions throughout the day your reservoir is slowly emptying. The more choices you make throughout the day, the harder it becomes for your brain, as your reservoir empties. And, you guessed it, The bigger the decision, and the more it requires self-control & willpower, the faster it empties your tank.

As your tank empties you start to act in one of two ways:

  1. Become Reckless: To act impulsively instead of thinking through the consequences. (“I want it & I’ll have it”)
  2. Do Nothing: Avoid using mental energy by making no decision at all.

I’m guilty of both of these and have found them creeping into my eating habits all too often.

I’d often feel so worn out the simple decision of “What’s for dinner?” could send me over the edge into a binge (Becoming reckless) or skipping a meal (Doing nothing). Both of which aren’t very helpful when you’re trying to reach a goal.

steps to dieting success


Most people seem to do the dietary equivalent of “planning to fail” when they don’t plan on what they’re going to eat, ahead of time.

For the majority of people, unless we’re planning ahead with our meals we’re not setting ourselves up for success as much as we could be.

This is what had alluded me for so long.

I had a great list of foods I could & couldn’t eat but was still having to make a decision come meal-time about what exactly from my list I was going to eat.

Success came to me in the form of creating a meal plan.

When I wrote a 2-day meal plan everything changed. The cycle of diet on & diet off came to an end and I finally started seeing sustained results. It allowed me to never be left wondering what I was about to cook and it also helped in knowing exactly what to get while grocery shopping (which can be very mentally draining).

The meal plan consisted of 8 meals I would circulate across 2 days.

Rather than having to rely on my self-control (Which is overrated), I now had a plan that helped me eat for my goals rather than eat for the moment.

Basic Example:

Day 1 

  • BreakfastOmelette
  • Lunch – Chicken Caesar Salad
  • Snack – Veggies with Guacamole
  • Dinner –  Steak with Roast Veggies

Day 2

  • Breakfast – Bacon & Eggs
  • Lunch – Tuna Salad
  • Snack – Protein Shake
  • Dinner – Shrimp Stir-fry

And then I’d rotate it through the week.

Monday – Day 1

Tuesday – Day 2

Wednesday – Day 1

And so on…

I’d leave Saturday blank because usually it’s spent with friends and we often eat out. However, I always ensure to plan ahead and get food from somewhere that does a good salad (Turkish or Mediterranean is particularly good for this).

When I get sick of this I simply change the 2 day meal plan to something else – And then “rinse & repeat”.

Some people prefer a full 7-day meal plan, and that’s fine. Figure out what works for you and then do it.

The point is not to follow it 100%, but rather, the goal is to never be left asking “What shall I have for dinner tonight?” leaving us open to our new found friend, Decision Fatigue.

I know I’m not the only one this has worked for. I’ve seen the simplicity of planning ahead work for countless people in achieving their goals, whether weight-loss or muscle gain. The best thing you can do to set yourself to succeed with healthy eating is create a meal plan.

What are some tips that have helped you stick to a diet?

Comment Below.

Images: 1 | 2 | 3

Ted Kallmyer is an ISSA certified Specialist in Fitness Nutrition, is an expert macros coach, and the author of The Macro Solution. If you need personal help reaching your weight loss/fitness goals see his nutrition & macros coaching options. Follow Ted on Instagram
Last Updated: June 30, 2019


  1. spectra311

    I do something similar and have been for a long time–I have also found that if I fail to plan, I plan to fail. Every week, I create a menu of things I will eat and shop for those foods at the store. I eat only the foods I buy then and if it’s some other food that isn’t on my plan, I don’t eat it. It really helps me focus on doing other things so I don’t have to worry about what I eat.

    • Dan Bolton

      Sounds like you have a good system, Spectra!
      Simple but powerful 🙂