# Minimally Cooked Potato Improved Glycemic Response Across Two Meals and Insulin Sensitivity of Rice–Potato Mixed Meals: A Randomized Controlled Acute Trial

## TL;DR

Hard-cooked potatoes mixed with rice may help reduce blood sugar spikes after meals due to their resistant starch content.

## Contribution

This study shows that hard-cooked potatoes retain resistant starch and improve glycemic control when combined with rice.

## Key findings

- Hard-cooked potatoes retained more resistant starch and total phenolics compared to soft-cooked potatoes.
- Replacing part of rice with hard-cooked potatoes reduced postprandial glucose and insulin responses.
- The hypoglycemic effect of hard-cooked potatoes did not last into the second meal but reduced overall glucose levels.

## Abstract

Objectives: This study aimed to investigate the possible association among texture, oral processing and starch digestive characteristics of hard-cooked (HP) and soft-cooked (SP) potato samples, as well as their acute postprandial glycemic and insulinemic response, when co-ingested with rice in a meal. Methods: HP and SP replaced one-third of rice carbohydrates. Postprandial glycemic and insulinemic responses were measured after test meal ingestion. In vitro experiments evaluated sample physicochemical properties. Results: HP retained more resistant starch (RS) and total phenolics than SP. When co-ingested with rice (HP + R), HP elicited more total chews, higher oral sensory exposure time, slower chewing frequency and longer eating duration. HP + R significantly reduced postprandial glucose iAUC, peak glucose and glycemic excursion. SP + R increased glycemic variability despite reduced iAUCglucose. HP + R also lowered iAUCinsulin, peak insulin and insulin resistance index. The hypoglycemic effect did not extend to the second meal, though composite iAUCglucose over 540 min was reduced. Conclusions: Partially substituting rice with hard-cooked potatoes may help stabilize postprandial glycemic and insulinemic responses, an effect largely attributable to RS retention.