Glycemic Intelligence: All Carbs Are Not Created Equal
By Robert Luby, MD
Note:This article is not meant as a substitute for proper medical advice. Please consult with your medical practitioner before making any major changes to your diet or using any type of remedy, herbal or otherwise.
There are countless diets and regimens for losing weight and improving health, so it is not surprising that many conceptual gems go unnoticed. In this article, I propose a diet and lifestyle that not only helps you lose weight but also may prevent or reverse many chronic conditions.
Instead of simply looking at the caloric content per serving of a food, this concept is based on the food’s effect on the blood glucose levels. There are two ways to measure this effect. The first method is called the “glycemic index”. This is a measure of the effect of 50 grams of a food compared with the effect of 50 grams of white bread. While the method has precision, it lacks accuracy. A normal person will rarely eat 50 grams of butter, for example, while it is very normal to consume 120 grams of orange juice or 230 grams of tomato soup.
A more accurate method is the measurement of the blood glucose effect based on grams of carbohydrate per typical serving size. The foods are then given a rating from 1-60. This number is called the “glycemic load” of the food. Eating foods with a low glycemic load has been proven to help with all sorts of chronic health problems.
It is helpful to split foods into three categories based on where their glycemic load number falls on the 1-60 scale. The first group is the 1-10 group. These foods should constitute the majority of a healthy diet because they have the lowest glycemic load. The 11-19 category should be consumed on occasion in smaller quantities but should not form a significant part of everyday eating. The 20+ category foods should be avoided. These foods tend to be unhealthy for a number of reasons.
Here is a summary of some common foods and their glycemic indices.
1-10
Kidney, garbanzo, pinto, soy, and black bean
Fiber-rich fruits and vegetables, like carrots, green peas, apples, grapefruit, and watermelon
Cereals made with 100 percent bran
Lentils
Cashews and peanuts
Whole-grain breads like barley, pumpernickel, and whole wheat
Whole-wheat tortillas
Tomato juice
Milk
11-19
Whole-wheat pasta and some breads
Oatmeal
Rice cakes
Barley and bulgur
Fruit juices without extra sugar
Brown rice
Sweet potato
Graham crackers
20+
High-sugar beverages
Candy
Sweetened fruit juices
Couscous
White rice
White pasta
French fries and baked potatoes
Low-fiber cereals (high in added sugar)
Macaroni and cheese
Pizza
Raisins and dates
There has been plentiful research demonstrating that the consumption of a low glycemic load diet is helpful for weight loss, diabetes prevention, and diabetes treatment. Less well known is the body of literature which has found beneficial effects of low glycemic load diets on cholesterol levels and the risk of cardiovascular disease, gall bladder disease, and possibly even colorectal cancer, breast cancer, and pancreatic cancer. A meta-analysis of scientific studies has estimated that a low glycemic load diet is associated with a 14% risk reduction in all diseases combined.1-7
In addition to choosing foods with low glycemic loads, there are a few other strategies which can lower the glycemic load of any meal. Modifying the rate of gastric emptying is one such strategy. Gastric emptying refers to the rate at which food exits the stomach and enters the intestine. When this process occurs rapidly, the rate of absorption of sugars and the glycemic load of a food/meal will be higher. Organic acids consumed at the start of a meal will slow the rate of gastric emptying, thereby decreasing the glycemic load. The most common organic acids in your kitchen are lemon juice and vinegar. Fermented foods (live kimchi or sauerkraut) also contain high amounts of organic acids. Cinnamon, although not an organic acid, also exerts this effect, but as it tends to be used on foods with high glycemic indices, it is less likely to result in the desired outcome.
The second strategy to lower the glycemic load of any meal is to consume foods with plenty of fiber. Fiber binds carbohydrates in the intestine and decreases the rate of absorption of sugars into the bloodstream. A good rule of thumb is that vegetables which grow above the ground (stalks, flowers, leaves, but not seeds/fruits) will contain the highest amounts of fiber. This makes intuitive sense because the fiber is necessary to resist gravity (stalks), maintain a horizontal position to capture sunlight (leaves), or support pollinating insects (flowers). Prime examples are asparagus and celery (stalks), broccoli and cauliflower (flowers), and any deep leafy greens (leaves). Happily, all of these foods taste delicious with lemon juice and/or vinegar. Therefore, the best strategy to lower the glycemic load of any meal is to consume a first course of live fermented foods or leafy greens (or stalks, or flowers) drizzled with vinegar and lemon juice.8-14
A final strategy to lower to glycemic load on the body is not dietary in nature. It is based on the knowledge that the levels of glucose in the blood are at their highest one to two hours following the start of a meal, and that physical activity initiates the insulin-dependent processes which result in lower blood glucose levels. Engaging in mild to moderate physical activity beginning 30 to 60 minutes after consuming a meal is an excellent way to ensure that the “postprandial glucose excursion” (the blood level of glucose after a meal) is kept as low as possible. Merely going for a walk one-half hour after completing a meal represents glycemic intelligence in action.
All these numbers and rules can get overwhelming, so here are a list of five golden rules of intelligent glycemic eating. These should help take the hassle out of lowering glycemic load and attaining overall health.
- Avoid the 20+ foods and beverages;
- Focus on low starch vegetables, satiating protein, and unsaturated fat;
- Consume vinegar, lemon juice or fermented foods at the start of meals;
- Emphasize eating foods high in fiber; and
- Engage in some form of physical activity about half an hour after every meal.
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