Carbohydrates. They are the last piece of the puzzle in our trio of macronutrients. Carbohydrates are the main source of readily available fuel for the body. The main types of carbohydrates are sugars, starch and fibre; as for food sources this includes fruits, vegetables, grains, legumes, and pretty much anything packaged. There are two main types of carbohydrates; simple and complex. Simple meaning that they are shorts chains of sugars including glucose and sucrose, while complex means larger chains including starch and glycogen (the storage form of sugars).
Once glucose is in the bloodstream it gets accepted into the liver, muscle or fat cells by a hormone you may know, insulin, which is produced by the pancreas. Once it is there in the desired cell, it can be used for fuel. Normal healthy individuals have a high sensitivity to insulin, meaning that the response is quick and the number of receptors are abundant in response to the glucose availability. However, when the cells are constantly being exposed to high levels of insulin, due to over-consumption of carbohydrates, our cells adapt by reducing the amount of insulin receptors. This causes insulin resistance, which means that the cells ignore the insulin and fail to transport the glucose from the blood to the cells. As a reaction, the pancreas pumps out more insulin, because it senses the high blood glucose and therefore causing higher levels of insulin needed for sugar to get into the cells. This is exactly how type 2 diabetes occurs as well as many other accompanying inflammatory diseases. The unfortunate part about this is that our body cannot tell the difference between glucose that is sourced from something like fruit and whole grains vs. the glucose sourced from artificial sugars and processed foods.
Of course there are additional benefits to consuming whole grains and fruit, such as the fibre which can help to slow the release of glucose into the bloodstream (I will talk about the importance of fibre in another post) and vitamins and minerals associated with whole food sources. However, it is important to keep the amount of carbohydrates consumed in check. Health Canada recommends choosing foods with more fibre and less added sugar and to have carbohydrates make up between 45-60% of your total calorie intake. In my opinion, I would stick with the lower end of that and supplement with an increase in fats due to there increased satiety and additional health benefits.
So, here is another Do’s and Don’ts list to help clear up any confusion.
- Vegetables, lots and lots
- Whole fruit sources
- Whole grain sources
- Oats, quinoa, brown rice
- Beans and legumes
- Lentils, kidney beans, peas, etc.
- Nuts and Seeds
- Almonds, peanuts, walnuts, sunflower seeds, pumpkin seeds, chia seed
- Processed, packaged and refined sugars
- Sugar drinks, pastries, cookies, candy, ice cream
- High-fructose corn syrup
- Fruit juice
- White bread
- Refined carbohydrates that are low in nutrients