The glycemic index (GI) is a ranking of carbohydrates on a scale from 0 to 100 according to the extent to which they raise blood sugar levels after eating. The risks of diseases such as type 2 diabetes and coronary heart disease are related to GI of overall diet.
Low GI — 55 or less . Low-GI foods, by virtue of their slow digestion and absorption, produce gradual rises in blood sugar and insulin levels, and have proven benefits for health. Have been shown to improve both glucose and lipid levels in people with diabetes (type 1 and type 2). They have benefits for weight control because they help control appetite and delay hunger. It also reduce insulin levels and insulin resistance.
World Health Organization (WHO) and Food and Agriculture Organization (FAO) recommended that people in industrialized countries base their diets on low-GI foods in order to prevent the most common diseases of affluence, such as coronary heart disease, diabetes and obesity.
most fruits and vegetables (except potatoes, watermelon), grainy breads, pasta, legumes/pulses, milk, yogurt, products extremely low in carbohydrates (some cheeses, nuts, cooking oil)
Medium GI — 56–69
whole wheat products, basmati rice, sweet potato, table sugar
High GI — 70 and above. Foods with a high GI are those which are rapidly digested and absorbed and result in marked fluctuations in blood sugar levels. Eating a lot of high GI foods can be detrimental to health because it pushes body to extremes. This is especially true if overweight and sedentary.
corn flakes, rice crispies, baked potatoes, watermelon, croissants, white bread, extruded breakfast cereals, most white rices (e.g. jasmine), straight glucose (100)
Benefits of Low GI foods
1. improve blood cholesterol levels
2. increase the body’s sensitivity to insulin
3. help people lose and manage weight
4. improve diabetes management
5. reduce the risk of heart disease
6. help manage the symptoms of Polycystic Ovarian Syndrome
7. reduce hunger and keep fuller longer
8. prolong physical endurance
Approximate GI values of some fruits
watermelon – 48
cantaloupe – 34
jackfruit - 41
chinese pears - 29
banana - 62
mango - 46
papaya - 42
apple - 48
pineapple - 56