Root Causes

Our focus should not be on the proximate causes of obesity (the imbalance of calories consumed versus burned), but rather on the root causes—why are we consuming more calories than we are expending? Specifically, we are interested in the causes themselves, not merely associated factors.

For instance, the Titanic sank after colliding with an iceberg, but suggesting the solution is merely to "avoid icebergs" is shortsighted. The real issue was that the ship was traveling too fast, and thus the more meaningful advice is to "reduce speed."

If we want to determine if a factor (let's call it X) causes another factor (Y), the methodology is straightforward:

1. Increase X. Does Y increase?
2. Decrease X. Does Y decrease?

What contributes to weight gain? There are numerous factors, with insulin being one of the most significant (as elaborated in my book, "The Obesity Code").

• Increase insulin. Does weight increase? Yes.
• Decrease insulin. Does weight decrease? Yes.

Avoid overcomplicating these causal relationships. The objective isn't to delve into the mechanisms by which insulin promotes weight gain—whether it increases appetite, lowers basal metabolism, or drives cravings. The key question is whether increased insulin leads to an increase in body fat, to which the answer is a resounding yes.

This understanding is well established; nearly all scientific research conducted since the discovery of insulin in the 1920s has demonstrated a correlation between insulin and weight gain.

When insulin is administered, weight gain is almost assured, irrespective of an individual’s willpower or exercise habits. This establishes a clear causal link.

Conversely, individuals with untreated type 1 diabetes—who lack insulin—experience fat loss until death.

In summary, insulin is a significant contributor to weight gain. While it is not the sole factor, it is a major causal element.

What is Insulin?

Insulin is a hormone produced by the pancreas, essential to human physiology. Our bodies operate on hormones—these chemical messengers dictate how we respond to various stimuli. Hormones themselves are neither inherently good nor bad; both excessively high and low levels can be detrimental.

For example, growth hormone influences growth—excessive levels can lead to gigantism, while insufficient levels result in stunted growth.

Thyroid hormone regulates metabolism—hyperthyroidism results in excessive activity and discomfort, while hypothyroidism leads to fatigue and sluggishness. The key takeaway is that all natural hormones must be maintained at appropriate levels; both high and low extremes can lead to health issues.

Insulin primarily functions in metabolism, signaling the body to store energy as glucose and body fat. Elevated insulin levels can lead to excessive glucose storage (type 2 diabetes) or body fat accumulation (obesity). This process is fundamentally straightforward.

Nutrient Sensors

Insulin serves as a nutrient sensor. After eating, insulin levels rise, indicating that food is entering the body and guiding its use. Different foods trigger varying insulin responses, with carbohydrates having the most substantial effect. Insulin levels fluctuate rapidly in response to food intake, but it is not the only nutrient sensor present.

Proteins (amino acids) activate the mTOR (mechanistic Target Of Rapamycin), promoting growth and protein synthesis. This makes sense, as amino acids provide the necessary building blocks for protein creation.

AMPK is another nutrient-sensing system that monitors energy stores within cells. It can be affected by any macronutrient (carbohydrates, fats, or proteins). For instance, consuming pure fat doesn’t alter insulin or mTOR, but it still influences AMPK since fat is a usable energy source. AMPK operates on a longer-term basis.

Our bodies are remarkably adept, employing three distinct nutrient sensors that respond to various nutrients and function differently over short, medium, and long-term durations, providing a precise nutritional overview of what’s available for utilization.

What is Insulin’s Role?

Insulin has multiple roles, one of which is to signal the body to store energy for future use. This ability is why we don’t perish overnight; our bodies can store energy as glucose and fat. When we consume food, we often intake more energy than our bodies can immediately utilize.

For example, if we have a hearty meal, we consume significantly more calories than required for that specific time. Thus, our bodies must store surplus energy for later use, as metabolic functions (brain, heart, kidneys, etc.) persist even during fasting. Insulin acts as the chemical messenger that instructs when to store energy and when to retrieve it.

Consider a refrigerator: after shopping, you may have more food than you can consume right away, so you store the excess for later. Similarly, after meals, insulin levels rise, signaling the body to store energy. The body primarily stores energy in two forms: glucose and fat. Glucose can be stored as glycogen in the liver. When fasting, insulin levels drop, indicating it’s time to utilize stored energy.

Essentially, our bodies exist in one of two states: the FED state (high insulin, storing calories) or the FASTED state (low insulin, utilizing calories). Insulin’s role is to instruct the body on when to store calories. When insulin levels are elevated, the body ceases fat burning and begins fat storage. In scientific terms, insulin inhibits lipolysis (fat breakdown) and glycogenolysis (glycogen breakdown). It initiates de novo lipogenesis (new fat creation) and glycogen synthesis (glucose storage).

What occurs if insulin levels are excessively high? It’s straightforward:

• Insulin directs the body to store sugar. If insulin levels are too high, we accumulate excess sugar, leading to type 2 diabetes.
• Insulin instructs the body to store fat. If insulin levels are too high, we accumulate excess fat, resulting in obesity.

When insulin levels are elevated, the body channels all available calories into sugar and fat storage. This energy doesn’t materialize from nowhere; it originates from the calories consumed. However, if all calories are directed towards storage, there are none left for the body’s essential functions (brain, heart, kidneys).

Recognizing a deficit in available energy (due to most calories going into storage), the brain—being intelligent—will either induce hunger to prompt further food intake (increasing Calories In) or reduce overall calorie expenditure. The mechanism is less important than the outcome, which remains consistent.

The Useless Concept of 'Calories'

Currency (money) serves as a useful means of measurement and exchange due to mutual agreement. In the realm of nutrition, the idea of "calories" can sometimes be misleading.

Excessively high insulin levels instruct the body to store calories at an elevated rate. This is insulin's inherent function, developed over a billion years. It is not that insulin is a "bad" hormone; rather, its levels can become problematic. This imbalance manifests as excessive glucose (resulting in type 2 diabetes) or excessive body fat (leading to obesity).

Obesity is fundamentally a hormonal imbalance, not merely a caloric one. It arises from elevated insulin levels causing Calories In to exceed Calories Out. Insulin represents a root cause, while calories symbolize a proximate cause.

The key takeaway is that insulin elevates the body's fat thermostat. Insulin contributes to weight gain. It's not merely about reducing calories; to achieve weight loss, one must focus on lowering insulin levels.