Blood Sugar, Insulin, and Fat Loss

I want to explain blood sugar and insulin in simple terms. As this illustration shows, our body has a system for balancing our blood sugar levels.  Here’s how the system works:

1.  The carbohydrates we eat are broken down into glucose, which is absorbed into the bloodstream.

2. The body detects the glucose and releases insulin.  This hormone (which comes from the pancreas) transports the glucose into our cells.

3.  This process is a constant balancing act—for non-diabetics, the body naturally keeps blood sugar from getting too high or two low (either extreme can be dangerous). 

You may think this only concerns diabetics.  But this process has multiple implications for fat loss and health.   Most well designed diets (the Zone, for example) take this into account. 

Stabilizing Blood Sugar

Sudden “spikes” in blood sugar are not good for fat loss.*  Let’s say I have an empty stomach and I drink a large soft drink.  The sugar (a simple carbohydrate) from the drink rapidly converts to blood glucose, and the body responds by releasing insulin. 

Here’s the problem: our bodies were not really made for refined sugar.  So the pancreas often overcompensates and floods our bloodstream with insulin.  Our blood sugar is lowered a bit too much, and end result is a “crash” in energy.  This is one reason we get sleepy after a big meal.

The health problems go far beyond the temporary crash.  Blood sugar/insulin spikes also tend to cause fat gain.  As I mentioned earlier, insulin transports glucose into our cells.  One of the primary destinations for glucose is fat cells. 

There’s another issue.  This blood sugar/insulin roller coaster can damage the body’s ability to effectively use its own insulin.  The end result is called insulin resistance, and it is a precursor to diabetes (by the way, exercise helps prevent insulin insensitivity). 

Here are some practical suggestions for stable blood sugar:

1. Try to include protein, fiber, and healthy fats along with carbohydrates in your meals.   This will slow down the digestion and cause a more gradual change in blood sugar.


2.  If you really have to eat sweets (yes, it’s OK to cheat), eat them after a meal.  Mom was right—eat your dinner before dessert.  The “real food” will slow the digestion of the dessert and thus reduce the insulin response (just keep in mind your overall calorie consumption). 

3. Know thyself.  Some of us are simply more sensitive to carbohydrates.  If you don't seem to do well with low-fat approaches, consider a low carb diet. 

Try these steps.  I bet you’ll end up with more stable energy levels and better success with fat loss.   

*There’s one exception to this rule.  Insulin spikes may be beneficial immediately following weight training.