Premise: if you still believe that carbs are bad and everyone should be on a low-carb diet read my carb article first. Instead, if you are a loyal Beary Strong reader go ahead! A normal carb tolerance is defined by the appropriate insulin release given the individual’s insulin sensitivity. What does this mean?
Most important thing first: the picture above has been taken at Choc Tree Edinburgh, an awesome bean-to-bar chocolatier and patissier. And to answer your question in advance: yes, we ate it all. Enough said, let’s get serious.
Two extreme scenarios
- Hyper-responders: you are insulin resistant (simplified: your cells do not take up glucose well in response to insulin) but you do well on a high carb diet that stimulates your insulin production enough.
- Carb-intolerant: you are insulin sensitive but your pancreas oversecretes insulin, then you are better on a low-carb diet because too much insulin without adequate stimulus for muscle hypertrophy can result in poor nutrient partitioning, excessive fat storage and low blood sugar.
Before you raise your hand and scream “that’s me!” take in consideration that both conditions of inappropriate insulin response are rare. Most of us have a normal carb tolerance and especially if you are cutting, there is not that much room to make adjustments in the one or other direction without going into a ketogenic diet (very low carb/high fat diet) or cutting fats under the recommended minimum. So what’s all the fuss?
What happens when you do not eat in line with your carb tolerance
Even if most of us have a normal carb tolerance, some of us still may not and that’s not fun if you want to build muscles or loose fat. An inappropriate insulin response causes elevated blood sugar levels (hyperglycemia), which is inherently inflammatory (for the nerds: it increases NFκB activation) and interfers with the inflammatory signal for muscle repair. Add high insulin levels and an energy surplus and you have high fat storage without muscle growth.
Assessing carb tolerance
Let me first destroy your dreams: carb hyper-responders are exceedingly rare and intuition is not a good predictor if you do better on low-carb or not since there is a lot of emotion going on with food choices. Some of us are simply carb-addicted and others are low-carb fanatics, just to make the point. Nevertheless, there are some points you can consider, if you really want to asses your carb tolerance:
- generally, the higher your body-fat, the lower your carb tolerance.
- the closer your genetic ancestry to Africa and India the higher your predisposition to insulin resistance and carb intolerance.
- healthy women have generally a normal carb tolerance due to their superior glucose and insulin metabolism. If you have policystic ovarian syndrome or similar conditions, you are more prone to be carb intolerant.
- older individuals, especially 65+ , are more prone to carb intolerance.
- highly trained individuals have a lower probability to have carb intolerance since muscle mass increases insulin sensitivity.
- daily exercising also imporves insulin sensitivity
Even if your genetic ancestry can give you hints about your personal carb tolerance, the genetic testing currently available on the market will not magically provide you the answer. You’re better at spending your money on a good coach 😉 . Still, there is a test you can do, but it requires a very strict lifestyle control and a high degree of meticulousness. It is based on the guidelines of the Bayesian Bodybuilding PT course. Everything needs to be the same during the testing: calories, macro partioning, including the satiety index of the high fat and high carb foods, the time of day, the timing in relation to exercise, etc.
- Day 1 and 2: take a defined amount of high carb food, e.g. whole grain bread and pair it with a defined amount of an arbitrary food, for example 30 grams of feta cheese.
- Day 3 and 4: take a defined amount of high fat food using the guidelines above, e.g. eggs and pair it with the same defined amount of the same arbitrary food as for the high carb meal, for example 30 grams of feta cheese.
Carb hyper-responder have a clear result towards the first meal feeling very energized, whereas carb intolerants get a strong ‘carb knock-out’ after which they get hungry again not long after. Most of us, will observe no difference.
Anti-nutrient and FODMAP sensitivity
Be also aware that some of us are sensitive towards grain’s anti-nutrients as well as FODMAPs and profit from reducing drastically their consumption of those foods because of reduced inflammation. Often, but not automatically, this leads to a low-carbish kind of diet.
Take home message
Most of us should not bother too much about carb tolerance and rather be paying attention on energy balance as well as building healthy habits (enough sleep, regular meals, stress coping…). And please, do not spend money on some shady genetic testing or metabolic typing. The knowledge is still not there. Nevertheless, if you are still concerned about it, you can use the guidelines and the test above.
Do you have the feeling to respond better on a high-carb diet or are you rather a fat lover? Share your thoughts with us in the comment section below. If you have enjoyed this article, it would make me incredibly happy if you share it to your friends. I’ll notice everyone of you and give you a friendly beary paw-shake 😉 .
If you are still struggling to find a nutrition that fits your goals and lifestyle, Stefan is very much looking forward to work with you: tasty recipes, personalized nutrition advices, kick-ass training and a 24/7 access to his email box for all your struggles are part of his online coaching.