(…continued from Tuesday’s post…)
The kinds of calories that we eat affect are bodies in different ways. For example, fat in the diet has no effect on our insulin levels. Protein generally does not have much impact on insulin levels either, but in excess amounts protein can also be stored as fat. Carbohydrates exist in many forms such as complex carbohydrates and simple sugars. The rate at which a carbohydrate is absorbed into the blood affects the body’s insulin response. In general, carbohydrates that are absorbed rapidly will cause higher increases in insulin levels. This can be a problem because insulin is a storage hormone. Broadly speaking, it promotes fat storage and inhibits our ability to burn fat. People who have chronically high insulin levels tend to hold on to their fat and will actually burn their muscle for energy when their glycogen stores are low. If you are insulin resistant, you are in a tough hole because you have decreased muscle mass (muscle at rest is metabolically active and burns more calories than fat) and your body has a hard time burning fat. That is why so many obese people have a hard time losing weight.
Glycemic index takes the body’s insulin response into account. High glycemic index foods tend to lead to higher blood sugar levels, higher insulin levels, insulin resistance, and over time, lead to higher body fat levels and increased risk for obesity, heart disease and diabetes. Some high glycemic index foods include: white bread, pasta, rice, many cereals, foods containing a lot of simple sugar (candy and most desserts), sweetened beverages and low fiber baked goods. Low glycemic index foods include: vegetables, most fruits, minimally processed grains, legumes, lean meats and natural fats. You can “Google” glycemic index and easily find references on the internet. But a simpler rule to follow is avoiding processed food. Processed food is mostly that stuff in the middle of the grocery store. You know what I’m talking about. Man-made food. Stuff that comes in a box that you add boiling water to, or that you get in the freezer section and you throw in the microwave or heat up in the oven. Ready to eat. That’s what I call factory food. It tends to have all sorts of stabilizers and preservatives in it. If the bacteria and mold won’t eat it, why should you?
Soft drinks, juices and sports drinks are basically sugar water. Remember the 4.2 grams of glucose in your bloodstream. Well, a 12 ounce can of Coca Cola contains 39 grams of sugar (high fructose corn syrup – we’ll save that battle for another day). Sorry to beat up on you Coke, it could just as easily be Pepsi. But let’s face it, I had to dig around on your website for 10 minutes and bounce my way through 5 pop-up pages just to get to your nutritional information. Are you trying to hide something? I don’t know many teenagers who limit themselves to a mere 12 ounces of a soft drink. So the average 12 ounces of soda contains almost 10 times your body’s active glucose load.
I think I can say with a degree of certainty that we consume too much sugar. In fact, the average American consumes 300 to 600 grams of carbohydrate in all its forms on a daily basis. It is no wonder so many of us are overweight. For healthy weight management I recommend between 100 to 150 grams of carbohydrate daily (that’s for an adult). It should come in the form of vegetables and fruits (yes, vegetables and fruits are nature’s carbs). If you read Dr. Grant’s post and are running regularly (please give it a try – you’ll only have yourself and Dr. Grant to thank) you can allow yourself more. Read his excellent introduction to running for novices.
Endurance athletes can burn through a lot of glucose. But please try to avoid processed foods and sugary/high glycemic foods in your diet, and I promise you it will be easier to maintain a healthy weight. Eat foods that are as unprocessed as possible and avoid anything that is “modified” “processed” “trans” “partially trans” “inverted” or any other industrial sounding word.