Let’s face it – weight change is complicated. You may want to increase muscle mass and, therefore, need to increase calories. Or, maybe you want to focus on body recomposition and lose some fat. Regardless of the reason, for many, “calories in = calories out” doesn’t feel true. While there is truth to these energy balance equations, there are a lot of nuances to the old expression that we’ll highlight here. Hopefully, some of this information can help you pinpoint why you might hit plateaus in your weight change goals.

Technically speaking, with all variables removed, we will maintain our current weight if the amount of calories we take in is equal to the number of calories we burn or utilize (calories in = calories out). Calories – a measure of energy – are taken in through food and used for energy in different reactions in the body. Some of that energy is for metabolic processes, some for movement, and a bit of energy is used for other daily living. Technically speaking, that does mean that if we take in more calories than our body needs we will gain weight, and if we take in fewer calories than our bodies use, we will lose weight. Those principles of energy transfers are true – but here’s where it’s tricky. We may not utilize, use, burn, or even absorb as much as we think. And because our bodies are wired for survival, they are very good at adapting to fluctuations in input.

For example, let’s say someone wants to build muscle. Technically, they could add a few hundred calories a day and eventually, over a week or so, gain a pound. But with this increase in energy, the human body is likely to subconsciously increase movement to compensate, and weight gain may not be as straightforward as expected.

Another example is someone looking to lose weight. They might decrease intakes and subconsciously reduce movement, similar to the example before. Or – what we see often – is that the baseline calories an individual takes in are so much lower than what’s needed for weight loss, that the individual’s metabolic rate adapts to the difference in intake. The body views drastic reduction in caloric intake as semi-starvation and quickly becomes adapted to utilizing far less energy.

Finally, the quality of the calories matters. For example the amount of calories in an ice cream sandwich does not impact our metabolic state the same way chicken with the same amount of calories does. For example, research has shown that individuals that tweaked their macronutrients to get more protein lost more weight, felt full longer, and had positive improvements in ghrelin/leptin levels. On the flip side, diets rich in processed food and sugar can trigger more inflammation and negatively impact our metabolic hormones.

So what do we do with this information? If we want to change body composition one way or another, how can we use the principles of calories in / calories out as a tool to help meet our goals?

First, we need to get good at tracking how much we are moving and what we are eating. As humans, we are not great at estimating intakes and the size of our plates can skew our perception of a serving. Tracking food intake may feel tedious, but a few days of recording what you’re eating can go a long way to bringing awareness to what’s happening with your typical eating routine. We like to think about this as meeting with your accountant to track where you are spending your money. We don’t suggest tracking macros and food intake every day, but checking in for a few days is essential to make sure you are eating enough of the right foods.

At STAT Wellness, we like the tool from Precision Nutrition that helps estimate energy needs. You can find it HERE. Then, take those numbers and plug them into an app like MyFitnessPal. Track your intake for a few days to get an idea of what is going well and where there is room for improvement. If you want to gain weight, you probably need to add food more consistently than you think. And if you want to lose weight – see how far off your current intake is from what is recommended. If there’s a big gap between where you are and what’s suggested, that could be a sign that your metabolism has adapted to lower intakes and needs some time to adapt to a higher calorie tolerance BEFORE weight loss is possible. Learn more about this concept of reverse dieting on our podcast HERE.

For all the nuances, don’t forget that we are here to help you navigate the data you collect about yourself so you can keep working towards your health and wellness goals!

Book a FREE 15 min nutrition consult HERE or call/text 404-254-5905 to figure out how we can help you reach your health and wellness goals.


Sarah Ganka, MS, RD, LD

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