Why Do Weight Loss Plateaus Happen? A Recent Study Found The Answer

Egis R.
4 min readDec 28, 2022
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If you thought parent-teacher meetings were bad, you never had a weight loss plateau. You do everything right — eating properly and exercising at least a few times a week — but the weight just won’t budge anymore. Losing weight becomes about as horrible as it’s possible to imagine.

So if you have been losing weight steadily but then plateaued for about four weeks or more, a recent study found the reason for it. And the explanation is pretty simple because there are only two possibilities:

  • As soon as you start dieting (read: apply calorie deficit), your basal metabolic rate, thermic effect of food, thermic effect of exercise, and non-exercise activity thermogenesis all go down and you start burning fewer calories in total. It’s known as metabolic adaptation a.k.a your body adapts to weight loss and defends against additional loss of weight unless further decreases in calorie intake are applied.
  • Your dietary adherence sucks mud. Consciously or unconsciously you start eating more than you realize and this erases the calorie deficit needed for weight loss to occur.

And so the study by Thomas et al aimed to find out which of those two plays a bigger role in reaching an early weight loss plateau:

Effect of dietary adherence on the body weight plateau: a mathematical model incorporating intermittent compliance with energy intake prescription
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They developed two mathematical models based on the first law of thermodynamics. If you want to feel your brain cells disappearing with little popping sounds, read through the study and try to understand how they did it. I didn’t bother.

One model was designed to determine the degree of metabolic adaptation required for the weight loss plateau to occur. Another model was designed to determine the degree of crappy adherence required to hit a plateau.

They concluded that the lack of adherence rather than metabolic adaptation was the main factor predicting weight loss plateaus:

The evidence presented in this study indicates that even very high and unrealistic levels of metabolic adaptation do not affect the timing of weight plateaus. Rather, the seemingly innocuous intermittent loss of dietary adherence results in weight graphs with 6-mo plateaus, and these results point to the sensitivity of dietary adherence in determining the kinetics of weight loss.
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Egis R.

I’m Egis, an online weight loss coach who has heightened BS sensors for fitness & nutrition. Only evidence-based & sustainable fat loss. www.absscience.com