Which statement best describes the glycemic index (GI) in relation to carbohydrate foods?

Which statement best describes the glycemic index (GI) in relation to carbohydrate foods?

• A. It measures the exact amount of carbohydrate in a serving.
• B. It ranks carbohydrates by their ability to raise blood glucose compared with a reference food.
• C. It remains constant regardless of serving size.
• D. It is identical to glycemic load.

Answer: (B)

Glycemic index describes how quickly the carbohydrates in a food raise blood glucose, using a standard reference food for comparison. This is why it’s the best description: GI focuses on the rate of glucose response, not the amount of carbohydrate in a serving. The GI value is determined by testing a fixed amount of carbohydrate from the food (often 50 g) against the same amount from the reference food and seeing how fast glucose rises. The other statements don’t fit as well. Measuring the exact carbohydrate content in a serving is about quantity, not the speed of glucose rise. Glycemic load differs from GI because it also accounts for how much carbohydrate you actually eat in a serving (GL = GI × carbohydrate per serving / 100). The idea that GI remains constant regardless of serving size is a simplification; while GI is defined per a fixed carbohydrate amount, the actual blood glucose response depends on how much carbohydrate is consumed, which GL captures.

Glycemic index describes how quickly the carbohydrates in a food raise blood glucose, using a standard reference food for comparison. This is why it’s the best description: GI focuses on the rate of glucose response, not the amount of carbohydrate in a serving. The GI value is determined by testing a fixed amount of carbohydrate from the food (often 50 g) against the same amount from the reference food and seeing how fast glucose rises.

The other statements don’t fit as well. Measuring the exact carbohydrate content in a serving is about quantity, not the speed of glucose rise. Glycemic load differs from GI because it also accounts for how much carbohydrate you actually eat in a serving (GL = GI × carbohydrate per serving / 100). The idea that GI remains constant regardless of serving size is a simplification; while GI is defined per a fixed carbohydrate amount, the actual blood glucose response depends on how much carbohydrate is consumed, which GL captures.