98% of people who attempt to diet fail. Yep, that’s right, only 2% of people who lose weight are successful in maintaining that loss. According to Wing and Hill of Brown University, successful weight loss maintainers can be defined as “individuals who have intentionally lost at least 10% of their body weight and kept it off at least one year.” Most people are really good at temporary weight loss…we are just really shitty at keeping it off.

What gives? The effort, time and financial commitment it takes to lose weight is substantial. We restrict, we track every morsel, we say “no” to things we love. It is extrinsic motivation that keeps us plugging away no matter how hard it seems… The comments: “Girl, you look great, what have you been doing?”…”Wow, you have really slimmed down, what’s your secret?”  The sense of personal achievement: “Damn, I look good”, and then poof, it’s gone just as quickly.

The truth is, it’s not YOU…it is the process by which the majority of people lose the weight in the first place. OR, more frequently it is the years of ebb and flow dieting and non-dieting episodes that leads to metabolic adaptations and makes it more and more difficult to achieve results each time you “get back on the wagon”. Let me explain…

The first time you diet, for most people, results come relatively easily. You cut portions, you restrict unnecessary snacking, you limit late night Taco Bell runs, you add in another day at the gym, and off comes the weight. Because you are getting results, you continue to cut more and more calories to push the needle… After all, when you are getting noticed, it is worth it to be starving, right?’

Not so fast. Each time you lose weight, you become more and more metabolically efficient. No, this is NOT necessarily a good thing. Why? Becoming more efficient means that your Resting Energy Expenditure (REE), also called Basal Metabolic Rate (BMR) begins decreasing as well. Look at the representation below. You can see that REE accounts for 70% of the calories we burn in a given day.


If this rate decreases, then we are simply burning less energy each day in our everyday tasks. As your REE decreases so too does your Total Daily Energy Expenditure (TDEE). TDEE includes the REE/BMR as well as Non Resting Energy Expenditure (NREE) which can be broken down into:

  • Exercise Activity Thermogenesis (how much energy we produce during exercise)
  • The Thermic Effect of Food (the energy required to eat, absorb, process and assimilate the food we eat)
  • Non-Exercise Activity Thermogenesis (NEAT). This is energy expended in random daily movement.

Together these resting and non-resting components make up how much total energy we expend in a given day. We all know that we must burn more energy than we consume (creating a caloric deficit) to lose weight. So, as we become more and more efficient (burn less calories in a day), we have to keep reducing our intake in order to maintain a deficit, right?!

When you stay in a hypo-caloric state (calorie deficit/energy restriction) for an extended period of time, in addition to reducing your TDEE, this restriction also leads to:

1)  Changes in hormone circulation and regulation. Leptin, thyroid hormones, cortisol, testosterone, and insulin, all primary predictors of weight loss are all impacted by energy restriction.

2) Increased efficiency of the cells mitochondria. The more efficient our mitochondria, the less energy we have to expend during physical exercise…this means our energy expenditure for many tasks is lower and thus the calorie deficit between what we eat and what we burn becomes smaller. Weight loss is more challenging the more efficient we become at the cellular level.

So what happens when all these adaptations go into effect? Well…metabolic adaptation has been seen to last for up to 44 weeks, even after calorie intake returns to baseline (pre-dieting) levels. In other words, you are ready to stop your weight loss program, and transition into a maintenance plan. Thus, you start eating more calories again. You return to your pre-diet levels of intake. Unfortunately, if you do not make this transition the right way, the metabolic adaptations that occurred through restrictive dieting have not returned to baseline levels. You are still expending less energy, you are still highly efficient and your body is not burning the same amount of calories as it did before you began dieting.

So, often more quickly than you think, you can gain back and potentially even “overshoot” the levels of weight and more specifically, body fat you had before you dieted in the first place! This starts the vicious cycle of what we all know affectionately as the Yo-Yo! In a nutshell…calorie restrictive diets, without proper facilitation and coaching that will provide a GRADUAL, HEALTHY reduction allowing your metabolism to adapt and remain active enough, as well as a “reversing dieting” (See Layne Norton and SoHee Walsh’s ebook), process of gradual re-introduction of calories after the fat loss phase is complete can result in a lifetime of frustration and reduced ability to achieve fat loss results.

Bottom Line…Diets DON’T work, and in fact, they are one of the main culprits in failed weight loss, and weight regain. Weight loss must be a slow, closely monitored process. It should not be a quick fix. If it promises 50lbs in 50 days, Call BS, and run the other direction. Taking care of your metabolism, allowing your body to slowly adapt and being mindful of the impact of energy expenditure will set you up for a lifetime of healthy weight loss and maintenance.