As we saw on the previous post, all calories are not created equal. The calories that you are ingesting will affect your metabolism differently depending on their composition and their origin. The truth is: you can still get fat and unhealthy with a low calorie diet.

So what is important in a diet? Here are a few factors that you need to consider as well.

Blood sugar level  

One of the main causes of diabetes, cardiovascular diseases, or brain degeneration is an almost constant elevated blood sugar level, which promote inflammation. We eat bigger quantities than in the past, and the type of food that we generally eat (processed and sweet) elevates our blood sugar level more than before. If we compare the diet of someone living today compared with someone who lived 100 years ago, one of the most significant differences is the huge increase in sugar consumption. (https://www.bespoke.world/food-1/sugar-consumption-now-vs-100-years-ago). This results in a chronic state of elevated blood sugar level, leading to the modern diseases that affect our society today.  

Elevated blood sugar level is not only caused by consumption of sugar, it comes every time we eat. However, some type of food will elevate your blood sugar level more than others. For instance carbohydrates tend to raise blood sugar level quite easily and decrease the sensitivity to insulin, that hormone that your pancreas secretes in order to lower the blood sugar levels. For that reason it has been encouraged for people suffering from overweight issues or cardiovascular diseases to adopt a low carb diet. This is partly true, however some types of carbohydrates who contains high amount of fibers will have minimal effect on blood sugar levels. Most fruits and vegetables for instance contain fibers, and they will help to delay the speed at which the glucose is delivered in the bloodstream and hence won’t affect the blood sugar level in a drastic way. But how do you know if what you eat will make your blood sugar levels rise? You have to look at several factors such as the glycemic index and the type of sugar you are eating.  

Glycemic index 

The glycemic index of a food is the ability that it has to elevate your blood sugar level. Food rich in fibers therefore have a low glycemic index, whereas food poor in fibers will have a high glycemic index. The problem is that we over-consume food that have a very little amount of fibers, such as refined carbohydrates (white bread, sucrose and high fructose corn syrup for instance). That means that the glycemic index is high, and eating those food will cause a rapid spike in blood sugar level. That spike gives you instant energy, like the sugar high that young children have after eating an ice cream, but it is usually followed by a crash in sugar level: that’s the called reactive hypoglycemia. Your body just fought so hard to lower the level of sugar in the blood that now you have too little. You feel sleepy, and hungry, especially for something sweet because your brain knows that it will give you a quick spike in blood sugar level. So you eat some more refined carbs. And the cycle goes on and on. Until you get sick of living like that for years.  

Fructose, glucose, sucrose 

Another factor that influence your blood sugar level is the type of sugar you are eating. Fructose, glucose, and sucrose are all considered as simple carbohydrate. They have the same sweet taste under the tongue and the same amount of calories, but they are processed quite differently by our metabolism. Glucose is the best form of sugar for the body. It is quite easily processed by your body and it is the form of sugar that circulate into your blood stream. Fructose is found in fruits and vegetables, but also in sodas and juices. It has to be processed in your liver. Fructose doesn’t give you the same feeling of satiety than glucose, because it leads to more ghrelin release (more on this later). Fructose also produces more fat that glucose. If fruits and veggies are not really an issue because of their high amount of fibers, fructose in juices or sodas is a huge cause of elevated blood sugar level. Sucrose is your traditional table sugar, coming from beets or sugar cane. Sucrose contains both glucose and fructose. They both will be broken down separately when you consume it, and your body will favor glucose to use as fuel, leaving fructose to get stored as fat.

The type of macronutrients 

There are 3 macronutrients: carbohydrates, proteins, and lipids (or fats). Most diets in the past have tried to find the perfect ratio we should eat in a meal in order to optimize our health.  

  1. Lipids. For the longest time, fats were pointed to be responsible for making us fat. We were used to see a lot of “low fat” products at the grocery stores, as a part of a strategy of the food industry to lower the risk of obesity. The problem with that is that, as we mentioned earlier, the brain is mostly made of fat. Our brains need fat in order to function properly. Diets high in fat like ketogenic diets provide help for people suffering with epilepsy and other neurologic disorders.  
  2. Carbohydrates. More recently, people have been pointing out carbohydrates as being an issue. Many studies have linked diets elevated in carbs and obesity or diabetes. This is partly due to the fact that some high carb food like bread or pasta will elevate the blood sugar level, which we just saw is a cause of overweight and inflammation. However, a recent study showed that this was not necessarily the case. Another study showed that actually a low carb diet could potentially be harmful.  
  3. Proteins. Out of the 3 macronutrients, protein is the one with the best reputations. Athletes are always told to eat a lot of proteins to help develop muscles gain without causing any increase in body fat. And proteins shakes are still taken on a daily basis by many professionals or amateur athletes. Protein have the advantage of the thermic effect: it requires energy for your body to process proteins, and that energy expenditure makes protein a more efficient source of energy in comparison with carbs or lipids who gets easily stored as adipose (fat) tissue. Another advantage is the high satiety effect of proteins: we feel full quicker by eating proteins so we eat less. But again, too much proteins can also be harmful for your body, especially for your kidneys.  

Bottom line

Instead of counting the ratio of your macronutrients, it is more important to understand that it is what type of macronutrients you are eating. Not all carbs are the same, and if all health specialists would agree that refined carbohydrates are harmful for the body, unprocessed carbs coming from whole food seems to be beneficial. Same thing regarding fat. Trans fat that you find in deep fried food for instance will damage your body, but unsaturated fat is definitely beneficial. After seeing so many failures and contradictions in marconutrients and calories-counting type of diets, it is time to acknowledge that those don’t really matter as much as we used to think. All of them can be eaten as long as they are minimally processed and diversified.