Resistant starch is healthy for you, feeding your microbiome and possibly slowing up digestion. It occurs in small amounts in many starchy foods, and in larger amounts in certain foods (green banana and raw potatoes have around 8g/100g). The amount of resistant starch in starchy foods like rice and potato is decreased by cooking but increased by then cooling it. Reheating does not seem to affect the amount of resistant starch in the finished dish. So reheated rice and potato seem to be healthier than freshly cooked. I've seen claims that doing this increases the amount of resistant starch in the food from as little as 25% to as much as 2.8 times.
But the question is, does that make rice or potatoes suddenly low carb? Sadly, not. Cooked brown rice is about 28g/100g carbs, with about 1.7g of RS. Best case scenario, after cooling that's 3g of starch converted into resistant starch, leaving 25g of starch - which makes it still a high carb food.
Similarly cooked potato has 0.6 g of resistant starch. Triple that gives you about 1g of starch converted to RS. So your potato has gone from 17g /100g to 16g. Again, still a high carb food. That extra 1g is probably very valuable to your microbiome, but the remaining 16g will still do a number on your blood sugar.
Sorry, disappointing I know😔
(table is from nutrition.org.uk/nutritions...
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