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Calories In Versus Calories Out

There is a lot of controversy around “Calories In Versus Calories Out.” Some say it is bad science, while others say it’s the “end all be all.” The truth is, it is not 100% one way or another. “CICO” falls in the middle. Energy balance is the foundation of what drives weight loss, gain, or maintenance, but CICO doesn’t take into consideration the quality of the energy source. Different food sources have different hormonal effects on the body. Different macronutrients have different effects on the body as well. The body does not process all calories the same way. Protein is the muscle-building block while carbs and fats are the fuel. The ratio of these will determine muscle growth, muscle loss, and overall body composition. CICO needs to be established first when determining how much an individual will eat but it doesn’t end there.

How do we measure what a calorie is? The definition of a calorie is the energy needed to raise the temperature of one kilogram of water by 1 degree Celsius. Essentially, if an individual eats more than they burned, the athlete will gain weight. If the individual eats less than what they burn, the athlete will lose weight. Lastly, if the athlete remains balanced and eats the same as they burned, the athlete will maintain their weight. To further dive into this, we must understand The First Law Of Thermodynamics, which states “energy in a system cannot be created or destroyed but can only change form.” This law applies to all energy systems, which includes human metabolism. Let's convert all of this science talk to an analogy that we can all understand. Let’s use a bank account. If you continue to deposit more money than you spend, this will result in the account growing. If you eat more calories than your body burns, then you store the unused calories as fat. This is what we call a “positive energy balance.” Now let’s look at a “negative energy balance.” If you were to spend more than you deposit in the account, eventually the account will dwindle down to nothing. This is how we’d view weight loss. Constantly making small withdrawals equals getting leaner and leaner.

We hear it all the time, “I’m in a calorie deficit and the weight is not coming off! Could it be my hormones?” Now hormones do play a big role. The genetic lottery is everything, but that doesn’t mean that CICO is irrelevant to you. So where do most individuals go wrong?

It is common for individuals to underestimate how many calories they are actually eating. This happens when we don't correctly weigh our food and/or don't log everything we consume.

Overestimating how many calories we burn is also very common and this is especially true if the individual is wearing a tracker. These trackers, all of which are good tools, are NOT accurate. They typically are an overestimation of what we burn. One study found that individuals overestimate how many calories they burn on average by 72%.

Too many “cheat days” or “cheat meals.” It is true, we should live in gray and indulge from time to time, but if we do this in excess it can essentially void all progress. For example, if you track correctly and finish the weekdays in a 1,500-calorie deficit but then eat 1,000 calories over what you're supposed to on Saturday, then you’ve essentially broken even for the week.

Tracking calories or even macros is claimed to be too obsessive or disordered, which to some degree it is, but we don't look at the individual who eats carelessly without portion control in the same light. Sitting down and just making a plate with no true understanding of the nutritional breakdown is, in my opinion, disordered. A diet full of predominantly processed foods where the individual is eating items like cereal and bagels for breakfast is disordered. I’m not saying everyone needs to weigh out their food and live in MyFitnessPal for the rest of their lives, but everyone should spend 6-8 months out of every year tracking their calorie intake. This teaches the individual then how to eyeball out portions correctly. It gives a better understanding of what 30 grams of protein looks like, a proper serving of carbohydrates & fat, and an understanding of how bad overconsumption of processed food really is. The message here is to take an interest in your nutrition the same way you take an interest in your favorite hobby. Your nutrition is the foundation for your longevity, don’t overlook the basics.

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