A reason to eat carbs

If you have spent any time in a startup hub or a discord server for AI engineers lately, you know the drill. Everyone is obsessed with optimization. We optimize our code, our token usage, and inevitably, our biology. The ketogenic diet has become the unofficial fuel of the builder class. It promises mental clarity, steady energy without the afternoon crash, and a lean physique that looks good on a demo day stage.

But as every founder knows, there is no such thing as a free lunch. In the world of systems architecture, when you optimize one variable, you often put strain on another. Our bodies are the ultimate legacy systems, and recent research is showing that the low-carb, high-fat configuration might have a critical vulnerability in the small intestine.

The Metabolic Trade-off

The core premise of the keto diet is simple: starve the body of carbohydrates until it switches from burning glucose to burning fatty acids and ketone bodies. For many, this feels like a superpower. You stop chasing the next sugar high and start burning the stored energy already on your frame. Some early studies even suggested this metabolic shift could help prevent certain types of colon cancer by changing the way cells in the large intestine behave.

However, new data is complicating that narrative. While a high-fat environment might be hostile to some tumors, it appears to be a catalyst for others. Specifically, researchers have found a concerning link between ketogenic environments and an increased risk of cancer in the small intestine. This is a classic case of why we need to look at the whole stack, not just one feature.

Why the Small Intestine Matters

In the tech world, we talk about the frontend and the backend. If the stomach is the initial processing layer, the small intestine is the heavy-duty backend where the actual nutrient absorption happens. It is a massive surface area designed to pull value out of what we consume. When you flood this system with a high-fat diet, you aren't just changing your fuel source; you are changing the cellular signaling within this critical organ.

The study suggests that the way our bodies break down fatty acids can actually trigger pathways that lead to rapid cell growth in the small intestine. In a healthy system, cell turnover is good. In a system that has gone off the rails, rapid cell growth is the definition of a tumor. The irony is that the very mechanism people use to lose weight and "get healthy" might be laying the groundwork for a different kind of systemic failure.

The Founder's Trap: Binary Thinking

Founders are prone to binary thinking. We like things that are 1 or 0. We like diets that are "all fat" or "no sugar." We want clear rules because our brains are already maxed out on the ambiguity of building companies. But biology is rarely binary. It is a series of complex, interdependent feedback loops.

We saw this with the early days of biohacking. People were jumping into ice baths and fasting for three days straight because the data said it increased longevity. Then we realized that for some, the cortisol spike from those stressors was actually doing more harm than good. The keto trend is following the same arc. It works until it doesn't, and the failure modes are only now becoming clear.

Risk Management in Biology

When you are building a product, you manage risk by diversifying your dependencies. If your entire app relies on one specific API, and that API goes down, you are finished. The same logic applies to your diet. By leaning so heavily into one macro-nutrient profile, you are creating a single point of failure.

The small intestine is relatively small compared to the colon, and cancer there is rarer, which is why it likely took this long for the data to surface. But rarity doesn't mean irrelevance. For the individual builder trying to stay in the game for the next thirty years, a high-fat diet that increases cancer risk in any part of the digestive tract is a bug, not a feature.

What Builders Should Take Away

I am not saying you should go back to eating processed sugar and refined flour. That is clearly a bad configuration for anyone trying to maintain high cognitive performance. But the "carbs are evil" narrative needs a patch. There is a middle ground that involves complex carbohydrates—the kind that provide fiber and support a diverse microbiome—without sending your insulin through the roof.

• Don't ignore the data: Just because a diet makes you feel focused today doesn't mean it isn't doing structural damage to your hardware over time.
• Diversify your inputs: Extreme diets are like extreme codebases; they are hard to maintain and prone to unexpected crashes.
• Context is everything: A diet that works for a sedentary office worker might be total overkill for a founder who hits the gym five times a week.

The goal isn't just to be productive this quarter; it is to be alive and functional for the long haul. If the latest research says that high-fat diets are creating a risk profile in the small intestine, we should listen. It is time to stop treating our bodies like a playground for extreme optimization and start treating them like the mission-critical infrastructure they actually are.

The most important thing a founder can do is stay in the game. You can't build the future if you are dealing with a preventable health crisis caused by a productivity hack.

We need to stop looking for the "one true diet" and start looking for sustainable balance. Carbs aren't the enemy; bad data and extreme behavior are. Adjust your settings accordingly.

Read the original at MIT Technology Review →