Carbs – the good, the bad and the ugly

When is sugar okay

Different kinds of sugar

Sugar metabolism and absorption



Carbohydrates have gotten a pretty bad reputation in the last few years – a not entirely undeserved reputation – for the bad effects that it can have on you. What is often not appreciated is that role of carbohydrates in exercise. So, I thought I’d write a little something that (with any luck) will make the whole subject less confusing.

I’m also going to simplify a bunch of information. Let me know if I went too far.

Carbohydrates and blood sugar 

Your body has regulation mechanisms to keep your blood sugar level constant. When it gets low, you get hungry.

And then, presumably, you eat. Through a wonderful and intricate process, the food gets digested, and your blood sugar goes up. And now, the important part:

The way in which your blood sugar changes depends on what carbs you eat.

This is described in a very simplistic way by a measure known as the Glycemic Index. You determine this by giving a group of volunteers a small portion of different foods and measure how much their blood sugar goes up over a specific time.

And then you end up with a chart that gives a value for each food (well, actually, two values. There is one scale where glucose=100 and another where white bread=100).

Why does this matter? Well, if you eat high glycemic foods, you get a spike in your blood sugar, which your body tries to regulate down with the release of insulin which pulls the sugar out of your blood and stores it as fat. Unfortunately, the insulin response is too much, which causes your blood sugar to drop, which makes you hungry, so you eat again.

Over time, this is believed to lead to insulin resistance, where the body stops responding to the insulin and the blood sugar stays high. At that point, you have type 2 diabetes, or are close to it.

This effect has been immortalized in the “I ate chinese food, but an hour later I’m hungry again”. Chinese food is often eaten with a lot of white rice, which has a fairly high glycemic index.

But, it’s not as simple as all that. First of all, it’s not just the glycemic index that is important but the amount of carbs in the food you eat. Carrots have a very high glycemic index but don’t contain much carbohydrate so they have little effect. The glycemic index is also a function of the whole meal, not just one component, and fats and protein both have a moderating impact on the glycemic index of carbs.

Sugar in your diet

effects of all sugars, including fructose

Sugar Absorption & Conversion

The ultimate destination of carbs is glucose, which is either used directly in the brain (and muscles), or stored in the liver and muscles and glycogen.

But first, the carbohydrate needs to be converted to glucose.

 glycemic index drawbacks.





insulin response





So, what do you think ?