Glycemic index of diets: importance beyond diabetes control

Glycemic index of diets: importance beyond diabetes control

Subject: Science and tech

Sec: Health

Glycemic Index (GI):

• The concept of the Glycemic Index (GI) was introduced by Prof. David Jenkins in 1981 to measure how different foods affect blood glucose levels.
  • GI is a number from 0 to 100 assigned to a food, with pure glucose arbitrarily given the value of 100, which represents the relative rise in the blood glucose level two hours after consuming that food.
  • The GI of a specific food depends primarily on the quantity and type of carbohydrate it contains, but is also affected by the amount of entrapment of the carbohydrate molecules within the food, the fat and protein content of the food, the amount of organic acids (or their salts) in the food, and whether it is cooked and, if so, how it is cooked.
  • Foods are ranked based on how they compare to glucose or white bread (GI of 100), and categorized into low (less than 55), medium (56-69), or high (over 70) GI.
• The Glycemic Load (GL) is calculated by multiplying the GI by the amount of carbohydrates consumed.
• While some nutritionists caution against diets high in GI due to their link to type 2 diabetes and support low GI diets, others argue that focusing solely on GI overlooks the quality of other macronutrients like proteins and fats.
• Significant research, including the international PURE study which included over 137,851 participants from 20 countries, supports the importance of GI and GL in diet.
• This research found that high GI diets are associated with a higher risk of major cardiovascular events and mortality, extending the concern over high GI diets beyond diabetes to include heart health.
• This is particularly relevant in regions like India and South Asia, where diets predominantly consist of high GI foods like white rice and wheat, leading to high GL and increased risks of diabetes and early-onset cardiovascular diseases.
• To combat these health risks, it is recommended to shift towards lower GI diets, including foods like brown rice, legumes, fruits, and vegetables, combined with regular physical activity.
• This could significantly help in reducing the incidences of diabetes and cardiovascular diseases.