Why the First Law of Thermodynamics Doesn’t Fit the Puzzle of Weight Loss

Eric Edmeades
2 min readAug 27, 2023

Losing weight is often seen through the lens of simple math: if you burn more calories than you consume, you’ll shed those pounds. This seems to align with the first law of thermodynamics, but when it comes to our complex human bodies, things aren’t quite that straightforward. Here’s why the first law of thermodynamics doesn’t directly apply to weight loss:

1. Humans are Multi-Fuel Engines:

Unlike simple machines, our bodies burn three different types of fuel — carbohydrates, fats, and proteins. This versatility makes energy expenditure much more intricate to calculate than a mere input-output equation.

2. Unseen Energy Burns:

Measuring energy burn is a tricky endeavor. It’s not just about how much you move or the calories in your food. Your body constantly expends energy to maintain its temperature, operate internal systems, move, and even think. These subtle energy burns are hard to quantify accurately.

3. More Than a Closed Loop:

The first law assumes a closed system where energy comes in and goes out. However, the human body is far from closed. It’s an open system that interacts with its environment in complex ways, making energy intake and expenditure dynamic and interdependent.

4. Evolutionary Survival Tactics:

Throughout evolution, our bodies adapted to survive challenging times. We store excess energy as fat for lean periods and release it when food is scarce. This means that weight loss isn’t solely about calories in and out; it’s also influenced by our body’s predisposition to conserve energy during scarcity.

5. Selective Metabolic Modes:

Our bodies have different metabolic modes that dictate energy allocation. Certain foods trigger these modes. For instance, consuming carbohydrates might signal a mode of energy conservation — your body prepares for scarcity by storing fat. On the other hand, if you consume a surplus of different types of food, your body might switch modes and start shedding excess weight.

Imagine a person trying to lose weight by cutting calories. If their body interprets this as a food shortage, it might react by clinging onto fat stores as a survival mechanism. Once the person resumes regular eating, especially with foods that don’t trigger a conservation mode, the body realizes the scarcity is over and begins to release stored fat.

In conclusion, the simple calorie math suggested by the first law of thermodynamics doesn’t capture the intricate web of factors influencing weight loss in our complex bodies. Energy balance is a piece of the puzzle, but it’s intricately woven into metabolic modes, evolutionary adaptations, and energy expenditure beyond visible movements. To navigate weight loss successfully, we must recognize the multifaceted nature of our bodies and their responses to different inputs.

#TheEvolutionGap #WILDFITWORKS #WILDFIT

--

--