Don’t worry, it’s not bad to eat carbs. But, critically look at the carbs you eat. Western cultures, and those that have adopted our food culture, have a surging epidemic of chronic illnesses. There’s good reason to think many of these chronic illnesses — Type 2 diabetes, cardiovascular disease, cancer, stroke, Alzheimer’s (sometimes called Type 3 diabetes) — start with hyperinsulinemia, a chronic elevation of insulin. Insulin is a hormone that tells your cells to grow by storing fat, making new proteins, and replicating. These are all necessary processes. However, when insulin is chronically elevated, cells are consistently in growth mode and rarely in repair mode. Repair mode allows you to burn fat, clean up misfolded proteins, and repair regularly occurring DNA damage. These are also necessary processes. Thus, it is healthy to cycle between growth and repair.
Being mindful of carbs in your diet can facilitate this cycle. Insulin is secreted in response to rising blood glucose levels, primarily caused by eating carbs. It shuttles glucose into the liver or muscle, or if those are full, stores excess as fat. Because every cell has an insulin receptor, it also signals to the whole body that there is enough energy for growth. Quickly increasing blood glucose by eating refined carbs or too many carbs causes a bigger insulin response. The problem with big insulin spikes is there’s too much insulin to clear quickly once the glucose is stored. Because it’s a growth hormone, it limits your access to draw energy from fat. As a result, your body is starving even though you just ate. It’s why you can feel hungrier or lethargic after eating hundreds of calories of junk food.
This reaction was good for our ancestors, who had seasonal, occasional access to fruit and needed to gorge on it to bolster fat stores for the winter. With Western diets, though, we can spike insulin several times a day, leaving us chronically hungry and tired while we gain weight. Further, chronic insulin elevation results in insulin resistance, requiring more insulin to be secreted to clear blood glucose. Eventually, insulin resistance causes poor blood glucose control, which is really really bad for you. It can take decades to reach this endpoint, but some markers along the way are inconsistent energy, adult acne, high blood pressure, brain fog, skin tags, dental cavities, belly fat, high triglycerides, and many more that researchers are now starting to associate with hyperinsulinemia or what doctors call Metabolic Syndrome.
Rule 1: I don’t limit non-starchy, high-protein, or high-fat vegetables. I limit starchy vegetables, fruits, and grains.
The good news is that hyperinsulinemia is treatable by eating to reduce insulin secretion. This is primarily achieved by watching our carb intake. You don’t have to eliminate carbs, just consider their effect. Their effect on insulin is determined by how quickly they are digested and enter your blood as glucose. Non-starchy (think high fiber per calorie like leafy greens), high-protein (like beans and lentils), or high-fat (like nuts) vegetables aren’t digested quickly enough to affect your blood glucose much. Starchy vegetables and fruits have more carb content and less fiber to slow down digestion, so I’ve found I can have 1 serving before my glucose starts climbing rapidly. Of course, fiber-rich options like berries are digested differently than fructose-rich options like grapes. Your reaction to different vegetables and fruits depends on your microbiome, so the glycemic index is a good reference for predicting your blood glucose response but not the end-all-be-all.
Grains can be tricky because even whole grains have undergone processing that makes them easier to digest. Plus, we often eat refined grains, like flour in bread or cereal. I’ve found that grains are problematic for me. That’s not to say I don’t eat them, just not every day. I try not to pair them with other quickly digested carbs. But I also embrace the motto everything in moderation, including moderation. If I indulge in a glucose-spiking meal, taking a walk afterward can shuttle some glucose directly into muscles without insulin.
Rule 2: I get at least 20 grams of fiber each day (but more often 25-30g).
I don’t shun carbs because it’s important to eat plants, and all plants have carbs. Plants are the only way to get fiber, which helps digestion and supports a healthy gut microbiome. The amount I list makes me feel best, but fiber tolerance can vary drastically based on the microbiome. People with ancestry closer to the equator, where plants are more plentiful, typically have a higher tolerance for fiber than those closer to the poles, where animals were the only food source for large portions of the year. If you have both kinds of ancestors, microbiomes are primarily inherited from the maternal line.
Rule 3: I eat about 100 grams of net carbs per day.
Based on the other two rules, I usually get around 100g of net carbs (total carbs minus fiber) each day. This isn’t really a rule, but if I eat 1 serving of starchy vegetables, fruits, or grains with each of my two meals, this is where I land. I could probably get away with more, especially because time-restricted eating ensures that I cycle between growth and repair each day. However, a few weeks after I stopped eating refined carbs, I stopped craving them as much. Those cravings have only diminished since then, and now I avoid them because I don’t like how they make my energy crash. I really like that my relationship with food now revolves around how it will make me feel, and breaking up with refined carbs was a large part of that change.
For more information about the role of insulin, see this talk by Dr. Jason Fung. He’s a nephrologist (kidney doctor) who saw the effects of diabetes on kidneys and tried to understand the disease model better, which led him to insulin. He’s an advocate for various forms of fasting to counter chronic diseases.
This is post 4 of 4 about nutrition for recovery. If I had to sum up the entire nutrition section, it would be to eat the least processed foods you can, ensure you get enough protein and fat, and limit your eating window. That is the simplest way to stick to all of the rules. For more topics about wellness, visit the wellness series page.