How carbohydrates are prepared is significant. Mostly, they (potatoes, rice, pasta, bread) are a source of starch when cooked. Starch is mostly broken down in the small intestine by maltase and salivery amylase, to glucose, which is easily absorbed straight to the bloodstream. There is a proportion of the starch that is so-called resistant starch. "Resistant Starch" is a terrible term really, because it suggests a substance that is resistant to being converted to starch. Its resistant to being broken down by maltase and amylase, and thats essentially through the formation of double bods in the polymer, changing how its folded, and therefore accessible by these enzymes. Double bonds are generally pretty stable. This form of starch is not broken down to glucose at all. Instead, its fermented in the large intestine by microbiota, to generate a range of short term fatty acids. These fatty acids are oxidized by muscle cells to Acetyl Co-A.
Cooling these cooked food to fridge temperature promotes the conversion of starch to resistant starch. Freezing the food increases that content. There's more than one type of RS though. RS4 doesn't occur in nature; its the type of polymerisation that occurs after gelatinisation of the food (ie cooking in water), followed by a rapid cooling cycle (put the food into the fridge).
Not all the starch is converted; though estimates seem to range widely, which I suspect is down to how the investigators measured starch content.
The RS content is a combination of the RS already in the food, and RS created through preparation process. Rice cooked in a rice cooker and chilled, will have a higher RS content than rice cooked in a pressure cooker. In fact the latter approach removes all variation in RS between rice varieties (Jasmine rice has the highest native content, short grain the lowest. The Chinese are looking at strains combining elements from Basmati-type rice with Japonica rice, to promote increased RS content). RS4 formation appears irreversible, so the content is not changed by warming the rice. though thats not necessary if you are spooning curry on top of chilled rice warmed to room temperature.
Thank you for your excellent contribution to this thread.
I heard about resistive starch, many many years ago, long before I was diagnosed with TD2. I never really paid it that much attention, cos I could not evaluate how significant the opportunity was. I'll give an example - it is accepted that Vinegar (or the more well known example - Apple Cider Vinegar) helps to alter the absorption of food, and helps to lose weight.
In the case of vinegar, the challenge for me was - how significant is the benefit, vs the cost and effort. I did put ACV on my salads once upon a time, for about a year. Later on, and now I think the main benefit is the salad itself, while the ACV, is a booster. So now I do not bother about the ACV, and just focus far more on getting a good portion of vegetables, and some fruit daily.
So that is the challenge with the topic of resistive starch - how relevant is this?, for the effort. How much more does one get out of this.
Are we solving the real problem, which is a predisposition to carbs. After several weeks of abstaining, I had a few biscuits recently, and I did not like them anymore, they were so obviously too sweet, I did not want to take any more. My taste buds alone told me - not good for me, and I stopped, and did not have any more.
I've already reduced the amount of carbs I eat, from the simple reasoning that :
1. The body can make glucose from proteins, and fats
2. It makes sense that - it is NOT sensible for a diagnosed T2 Diabetic, to be dosing heavily on carb dominant meals, kinda counter intuitive to be doing that, makes sense to reduce a primary source of "glucose".
My point being, if one has already weaned themselves off any carb dependencies, or sugar addictions, and the "dose" of carbs is already low, is there any benefit in investing the effort in resistive starch?
When I was 1st diagnosed as T2D, I had a long list of do's and dont's, and it became somewhat complex, to establish a routine. Now I've broken it down into the important things, and everything else is simply an optimisation.
The basics being - A low carb diet, with some fruit(small amount) and varied set of vegetables as the priority, and get as much activity as regularly as possible, and get enough sleep, and drink enough water or fluids, with anything else being incremental, a further enhancement to these basics.
Simplifying this lifestyle has helped make it sustainable, and also observe that I continue to lose weight, albeit somewhat slowly, even though I really do not do any significant portion control.
