The Wise Body: Understanding Weight Gain

We often hear that metabolism slows with age, and as a result we start to put on weight. The human body is a high-tech corporation, with trillions of workers and a marvel of biological evolution; can it really be so flawed? Let’s give it the benefit of the doubt and look for answers that might explain why.

Let’s start with the brain. In early childhood, the brain is a metabolic powerhouse, consuming up to 50% of the body’s total energy. As we grow and move through different phases of life, this demand steadily falls. By old age, the brain may use only 15–20% of our energy. The conventional view sees this decline as degradation. But if that were true, a two-year-old with a hyperactive brain would be the smartest being alive, and a person in their 50s would be cognitively diminished. We know this isn’t the case. We value experience, wisdom, and the ability to handle complex situations: hallmarks of a highly developed and, crucially, a highly efficient brain.

This lowering of energy consumption, therefore, is not a drop in performance, but a surge in efficiency. The brain learns, optimizes its pathways, and does more with less. It becomes a master of its domain, requiring fewer raw resources to operate brilliantly.

Now, let’s apply this lens of efficiency to the entire body. Just as the brain becomes a refined processor, so does the whole system. In youth, we need more calories to fuel rapid growth and a less optimized engine. Over time, as we become more efficient, we generate an abundance of energy from the same inputs. Logically, our appetite should fall to match this new, lower demand. But here lies our modern struggle: we don’t listen to it.

We become attached to our established eating patterns, the same hearty breakfasts, lunches, dinners, and snacks. Our bodies, now running like sleek machines, have no need for all that fuel. Yet we keep pouring it in. The initial storage of excess is a natural buffer, but over time, this storing becomes chronic, like a miser hoarding long past necessity.

The reason we gain weight is not because the body is breaking down. It is because the body has become highly efficient.

Consider a car analogy. An older car might need a full tank of petrol to travel 500 kilometers. Now, imagine you get a new, doubly efficient model. That same full tank could take you 1,000 kilometers. If, out of habit, you insist on filling the tank again after only 500 kilometers, it will overflow. You cannot fuel an efficient machine with the same quantities you used for an inefficient one.

Our bodies are no different. As our personal “engine” becomes more efficient over decades, we must recalibrate how we fuel it. The tragedy is that we often fail to do so. We are stuck, not because of a failing metabolism, but because of an overwhelming abundance of sensory stimuli that confuse our internal systems.

Our body knows only the basics: carbohydrates, fats, proteins, minerals. But our tongue is bombarded with a dizzying array of compounds, flavor enhancers, and artificial taste molecules that hijack our behavior. This constant variety prevents calibration.

Think of a specialized office worker. Given one type of task consistently for years, they become an expert, optimizing their work for peak efficiency. But if you change their duties daily, giving them a broad but shallow workload, they can never specialize or optimize. They remain in a state of generalized confusion.

This is precisely what happens to our taste receptors. By offering them a relentless variety of intense, processed, and chemically modified tastes, we overwhelm them. They become confused and lose their ability to discern and regulate. They are like a watchman at a gate who has been told that everyone is a VIP, that no one can be turned away. What use is the watchman? He becomes redundant, standing idle as everything floods in. When every taste sensation is uniquely intense and different, the system is overloaded. It doesn’t know what to let in or what to refuse, so it lets everything pass, overloading the digestive system with far more fuel than the efficient engine needs.

Therefore, the core problem is not our digestive system, our metabolism, our brain, or even addiction alone. The key issue is an overabundance of confusing stimuli. This confusion disrupts the delicate system meant to analyze inputs and decide what should go in, and in what quantity. We have lost the wisdom of calibration.

This, in turn, increases stress on the digestive system, which then impacts other systems. As this stress percolates down the chain, it modifies signaling events and activates stress adaptation pathways. To counteract this stress and protect itself, the body starts to store more. It stores not out of greed, but due to stress and the perception that energy may not be enough; it is a survival mechanism meant to prepare for future periods of strain.

The path forward requires respecting our body’s wisdom. To support its hard-earned efficiency, we must decrease inputs so as not to strain the system with misleading signals. We must simplify. This means choosing foods that are local, unprocessed, and have a genuine taste: foods that don’t send confusing chemical signals. We must cut down on the sheer variety that overwhelms our internal gatekeeper.

In the end, weight gain viewed through this lens is a story of success mismanaged. Our brains and bodies have worked for decades to become elegant, energy-saving systems. They have learned to do more with less. The weight we carry is often the physical manifestation of our failure to update our habits to honor that efficiency. It is not a sign of decline, but a plea for us to become wiser partners to our own refined and capable selves. We must learn to fuel the efficient machine we have built, not the youthful one we once had.