Raw potatoes are not recommended for heartburn relief and may actually cause digestive problems.
Raw potato starch is classified as resistant starch type 2 (RS2), which resists digestion in the small intestine according to the University of Sydney GI Database. While this might seem beneficial, raw potatoes contain protease inhibitors that can reduce protein digestibility and potentially cause digestive discomfort.
More importantly, raw potatoes contain anti-nutritional factors including trypsin inhibitors and chymotrypsin inhibitors that can interfere with proper digestion. These compounds are neutralized through cooking, which is why potatoes should always be consumed cooked.
For digestive health benefits, the research shows that cooked and cooled potatoes are far superior. When potatoes are boiled and then cooled at 8°C for 24 hours, they develop retrograded resistant starch (RS3) that acts as a prebiotic. Studies by Martínez et al. (2010) in the ISME Journal found that resistant starch from retrograded potato increases beneficial Bifidobacteria and Lactobacilli populations in the colon. Phillips et al. (1995) in the American Journal of Clinical Nutrition demonstrated that consuming 30g/day of resistant starch from retrograded potato increased fecal butyrate concentrations by 38%, which supports gut health.
If you're seeking natural heartburn relief, cooked and cooled potatoes in dishes like potato salad would be a safer, more effective choice than raw potatoes, while providing proven digestive benefits through resistant starch formation.