Metabolism
Insulin resistance is an underestimated problem caused by more than just carbohydrate intake. Iron levels, environmental toxins, and other factors play a crucial role in your insulin sensitivity.
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We're familiar with insulin resistance, but also with insulin sensitivity—the opposite of resistance. Insulin is perhaps our most important hormone. It is—contrary to what is often claimed—not just a "storage hormone" that makes you fat and sick. Quite the opposite. Insulin and what's called "insulin signaling" in our cells normally works like a soothing balm. It serves to build and maintain cellular structures, and insulin works anti-inflammatory and function-preserving. In other words:
So far, so good. There are essentially two reasons why insulin stops working well. One reason is why low-carb diets exist in the first place: if you constantly overwhelm cells with excess insulin, they shut down and don't want any more insulin. Hence the idea: simply remove from your diet what normally triggers an insulin spike—namely, carbohydrates.
The logical flaw in this approach is that a) normal carbohydrate consumption actually causes your body to process carbohydrates better over time and therefore requires much less insulin, and b) there exist some of the healthiest indigenous populations in the world, which have far lower insulin levels and much better metabolic health than we do, and they primarily eat carbohydrates. Sure, you can debate wheat flour and refined carbohydrates, but the fact remains that good insulin sensitivity doesn't necessarily have anything to do with carbohydrate intake. Quite the opposite, in fact.
What many people completely overlook is that defective insulin action—insulin resistance—doesn't only occur "top-down," i.e., through carbohydrate excess. It can also happen "bottom-up." In other words, the cell, for whatever reason, doesn't do what it's supposed to do—like burning energy—and as a result, it shuts down and inhibits insulin signaling. This causes insulin resistance to develop gradually and without our conscious involvement. In this case, even the best low-carb diet won't help anymore.
We've addressed this topic frequently—in our blog, in our books, everywhere. And yet, for some inexplicable reason, it's still not widely understood. Here are a few examples:
...and especially not when it comes to eating organisms from the sea. Seafood is often literally a garbage dump, loaded with all the substances we pour into the oceans. Anyone who regularly consumes fish will inevitably expose themselves to a huge amount of pollutants. Back in 2011, an important study showed that farmed salmon containing persistent organic pollutants caused insulin resistance and obesity in an animal model. Who would want to eat that?
Just a few years ago, a study was published showing that "38 percent of the 175 countries analyzed had populations exposed between 2001 and 2011 to weekly methylmercury doses far exceeding the maximum safe level for fetal development." Why? Because heavy metals—in this case the highly toxic organic methylmercury—have massively accumulated in the world's oceans over many decades. You can assume the same for essentially all other environmental toxins.
This means: good insulin sensitivity, a normally functioning energy metabolism, depends on many factors. In our Western world, however, it often depends on factors we don't even recognize. We're slowly eating and living ourselves sick—and then believe that simple carbohydrate restriction will make things better again. The simplest starting point: just try eliminating fish from your diet for a few weeks and see what happens. Plant-based and vegan diets are undoubtedly so successful and valuable in part because they remove exactly what often impairs insulin sensitivity from the menu. Red meat (= lots of iron), fish (see above), eggs too (still often with very high dioxin levels!), and other things. Beyond that, you shouldn't forget that heavy metals and environmental toxins especially love to accumulate in animal organisms and are often in a particularly bioavailable form there.
This doesn't mean you shouldn't eat animal products. No, they're extremely nutritionally valuable and irreplaceable. But you should consider whether it's a good idea to eat low-carb and then consume a kilogram of salmon every week, five eggs daily, or 300g of beef. That can very quickly become very harmful to your insulin sensitivity. And then you wonder why.
So the circle closes. For the new year, we're resolving to achieve good insulin sensitivity.
