Workout of the Day

Why Your Crash Diet Isn't Working


I’ve made my position on crash diets pretty clear in the past, but in case you need a refresher, here goes: I’m not a fan.

First and foremost, they generally don’t work. More specifically, they tend not to pan out in the long run. Sure, your 2 week “cleanse” where you consume nothing but expensive juice or lemon juice, cayenne, and maple syrup, or the leading series of weight-loss powders will lead you to lose a considerable amount of weight in the short term. Extreme calorie restriction tends to have that effect. But give it a few months and that lost weight will be right back where it started, and sometimes there will be even more than you started with. The success rates for long-term maintenance of weight lost on a crash diet is pretty dismal.

Why? Because by definition, a crash diet does not establish a new equilibrium for your body. Think of it this way: for better or worse, your body has a rough idea of where it “should” be, both in terms of body weight and energy consumption. Of course there are countless factors that can change this from day to day, but you have an equilibrium that your body trends towards: “I weigh X amount, I need X amount of energy every day.” When you participate in a short-term crash diet, you do nothing to change this equilibrium point. You may go from 185lbs to 165lbs in the span of a month by dropping your daily calorie intake from 2500cals to 600cals, but your body’s equilibrium point is still going to be somewhere around 185lbs and you’re still going to be hungry for about 2500cals of food. Crash diets simply do not allow the body time to adapt -- they shock the system for a short burst of time, your body undergoes extreme change (equilibrium is heavily disrupted), and then the body responds, as soon as things go back to something more “normal,” by trying to get back to equilibrium ASAP. And sometimes, it even overshoots equilibrium.

On top of this, crash diets do nothing to positively modify behaviors. They deal in extremes. Rather than training sustainable habits and moderation, they lean on extreme changes that you’re only able to participate in because you know that they’re not sustainable. This ultimately means that these crash diets generally diminish health, fitness, and healthy lifestyle habits. Put another way, you’re not going to be very eager to kickstart a new exercise habit or apply yourself to your training when your body’s struggling to even remain upright and functional at your desk at work because all you’ve eaten for the last week is grapefruits.

Beyond the physiological problems with crash diets, they are a product of a way of thinking that assumes long-term, habit-based problems can be resolved with short-term trickery. Somewhere in your head, you’ve convinced yourself that even though it took 4 years of poor eating and exercise habits to get you here, life owes you a quick 2-week fix. Consider this a friendly virtual “snap out of it, you fool” slap across the face. That way of thinking is going to do more harm to your health, fitness, and physique than anything else.

The aim of dietary change should be sustainability of practice and results. This doesn’t mean that there’s no room for shorter-term restriction followed by letting up on the reigns a little bit (a sort of in-season/off-season effort), but unless you set your sights on changing your daily habits and creating a sustainable practice for the long haul, you’re signing yourself up for the yo-yo ride of perpetual poor health and disappointment.

This stuff takes time. Accept that, and learn to love the process!

- PS


  • 8 min EMOM

    • Min 1: Max strict L-chin-ups

    • Min 2: 30s plank


  • 16 min AMRAP

    • 400m run

    • 20 shoulder to overhead (115/80)