Pre-Diabetic Study Shows RD43 Rice Reduced Insulin Resistance and Visceral Fat Without Calorie Restriction
"34 pre-diabetic people swapped their normal rice for RD43, two meals per day for 12 weeks. By the end, the RD43 group had significant drops in fasting glucose, drops in fasting insulin, drops in HBA1C, but their homir, their direct measurement of insulin resistance dropped. They also lost weight. They lost fat and they lost waist circumference, which means they probably lost visceral fat."
About this episode
Health and metabolism expert Thomas DeLauer examines RD43, a specially bred Japanese rice variety that produces minimal blood sugar and insulin spikes despite having identical calories and carbohydrate content to regular white rice. DeLauer explains that the key difference lies in the molecular architecture of the starch itself, not the amount of carbohydrates. RD43 was developed through traditional crossbreeding to create a high-amylose rice that forms V-type crystalline structures where amylose wraps around fatty acid chains, making it resistant to digestive enzymes and preventing much of the starch from converting to blood sugar. Two significant human trials demonstrate the rice's metabolic impact: a 12-week study of 34 pre-diabetic individuals showed significant reductions in fasting glucose, insulin, HbA1c, and insulin resistance, plus fat loss that appeared independent of calorie restriction. More dramatically, a clinical therapeutics study of 96 women with gestational diabetes found that only 6 percent of those eating RD43 needed insulin therapy compared to 23 percent eating regular jasmine rice, a 73 percent reduction. Of those in the jasmine group who reached the threshold for needing insulin, 10 out of 11 were able to avoid it after switching to RD43. DeLauer also provides practical guidance for home cooks, explaining how to engineer similar benefits from regular rice through cooking, refrigerating overnight, and reheating, a process called retrogradation that increases resistant starch by approximately 2.5 times. He recommends adding small amounts of olive or coconut oil during cooking to promote formation of protective starch complexes, and suggests aged basmati rice as the closest mainstream alternative to RD43.
Key takeaways
- Thomas DeLauer presents RD43, a Japanese rice variety that produces minimal blood sugar spikes despite having identical calories and carbs to regular white rice due to its unique starch architecture.
- A gestational diabetes study of 96 women found RD43 rice reduced the need for insulin therapy by 73 percent, with only 6 percent requiring insulin compared to 23 percent eating jasmine rice.
- A 12-week trial of 34 pre-diabetic people showed RD43 rice significantly reduced fasting glucose, insulin, HbA1c, and insulin resistance while promoting fat loss independent of calorie restriction.
- RD43 forms V-type crystalline structures where amylose wraps around fatty acids, creating starch that passes through the small intestine undigested and gets fermented in the colon instead of spiking blood sugar.
- Cooking regular rice with small amounts of olive or coconut oil, refrigerating overnight, and reheating can engineer similar benefits by increasing resistant starch approximately 2.5 times compared to fresh rice.
- Aged basmati rice with high amylose content is recommended as the closest mainstream alternative to RD43 for those unable to source the Japanese variety from Asian markets.
- Adding vinegar or lemon juice to rice further slows starch-digesting enzymes, creating a stacking effect with cooling and fat addition to maximize blood sugar control.