Nutrition: Carbohydrates Chapter 12

Glycemic Index


Sweet Scale: The Glycemic Index

The Glycemic Index classifies hundreds of foods according to their impact on blood sugar. The GI indicates how intensely and rapidly the given food will influence glucose and insulin levels when consumed. Originally developed as an aid to diabetics, it can be referenced effectively by anyone to maintain a healthy weight and reduce the risk of chronic conditions. READ MORE

How it Works

Indexed foods are ranked from 0 to 100. Glucose, being the sugar that cells can immediately use as food, is the GI’s measuring stick and tops the index at a rating of 100. Foods in the lower range, which include many complex carbohydrates, are absorbed into the blood slowly. With a gradual and prolonged effect on blood sugar and insulin, low GI foods have a proven health benefit.

The conviction of GI proponents — which include the World Health Organization, the National Institutes of Health, the Harvard School of Public Health, and others — is that diet should be based on low GI foods to prevent and even treat diseases that are in epidemic proportions in the Western world; namely, diabetes, obesity, and cardiovascular disease.

The index offers accurate and actionable dietary information while catering to the pervasive “good-food / bad-food” mentality engendered by diet fads and the weight-loss industry. LESS


Three Ways to Use the Glycemic Index

  • Research the foods you most commonly consume and seek low-GI substitutes for high-GI meals. If the majority of your current food choices fall on the high side, set a short-term goal of having at least half of your diet shifted to foods indexed at 50 GI or less. Begin with just one substitute at a time.

  • Athletes may map meals based on glycemic indexes in the low to moderate ranges for the purpose of increasing glycogen stores prior to training and competing.

  • With the aid of guidelines established by a personal physician, anyone with hypoglycemia or hyperglycemia — including prediabetics and diabetics — can plan meals so that fluctuations of blood glucose levels do not exceed designated limits.

High Praise for Low GI’s

Per the University of Sydney, which maintains the official Glycemic Index website and GI Database, the health benefits of high GI and low GI diets stand in stark contrast.

Benefit High or Low?
Helps people lose and manage weight Low GI
Increases the body’s sensitivity to insulin Low GI
Improves diabetes management Low GI
Reduces the risk of heart disease Low GI
Improves blood cholesterol levels Low GI
Can help you manage the symptoms of PCOS Low GI
Reduces hunger and keep you fuller for longer Low GI
Prolongs physical endurance Low GI
Helps re-fuel carbohydrate stores after exercise High GI

Any questions?



Smart Substitutions

High and Low, Good And Bad The Glycemic Index does not aim to label foods good or bad; if anything, it’s a welcome departure from such weight-plan lingo. What the system can do effectively is help you establish a new barometer for balance in your diet. READ MORE

For example, health authorities recommend that we are to obtain about half our calories from carbs, with only loose guidelines on which carbohydrates. If they’re all coming from the 75-or-better range on the GI scale, the recommendation can actually lead to hyperglycemia and the attendant health concerns.

Consult a physician to determine the appropriate blood-glucose target range for you. Then, to learn more about which foods belong on your plate, visit As you explore the index, note where some “treats” are unexpectedly low on the scale, and some nutritious foods surprisingly high.

Trading a high GI food for a low GI substitute can help prevent big fluctuations in blood sugar and insulin levels — and be a valuable step toward better health overall.

INSTEAD OF... ENJOY... Glycemic Index Improvement
Food (weight) GI Index Food (weight) GI Index GI Δ
Sticky Rice (150g) 87 GI Quinoa (150g) 53 GI 34
Watermelon (120g) 72 GI Grapefruit (120g) 25 GI 47
Corn Chips 72 GI Potato chips 56 GI 16
White bread (30g) 70 GI Pumpernickel bread (30g) 46 GI 24
Baked White Potato, no skin 98 GI Kidney Beans (150g) 19G 79


The material on this site is for informational purposes only and is not intended as medical advice. It should not be used to diagnose or treat any medical condition. Consult a licensed medical professional for the diagnosis and treatment of all medical conditions and before starting a new diet or exercise program. If you have a medical emergency, call 911 immediately.