Consuming carbohydrates in the diet is always a hot topic of debate, especially when we talk about diabetics. The moment you are diagnosed with diabetes, it is recommended to steer clear of rice, potatoes and everything starch. But is it ideal for diabetics to avoid carbs completely? Ideally, around half of our calories should be consumed in the form of carbs. However, there is no persistent evidence recommending the exact amount of consuming these. Typically, the quality, as well as the quantity, is what matters when one, especially a diabetic has to consume carbohydrates. One such type of carbohydrate is resistant starch (RS).
They are a type of starch that are resistant to gastric enzymes and take a long time to get digested and absorbed. They escape digestion in the stomach and small intestine and enter the large intestine, usually the colon, where they are acted by local resident bacteria. Thus, in this respect, they somewhat work similarly to dietary fibre.
Glucose vs starch
Glucose is basically a single sugar molecule that the body can directly absorb from the intestine. Starch, on the other hand, is massive and is formed by two or more types of sugars bonded together. They must be broken down into simpler molecules in the gastrointestinal tract before absorption. Based on this property, starch usually takes a long time to digest unlike glucose, and aid in delaying the insulin spike and/or postprandial hyperglycemia in diabetic individuals.
Resistant starches are naturally present in some foods and there are some ways that can be followed to cook, store and prepare our foods in such a way that they become starch resistant.
Foods with naturally occurring starch includes:
- Whole cereals
- Raw banana
- Root vegetables
Also Read: Stop noshing on starchy snacks as study says it can lead to heart problems
Resistant starch and its effect on blood glucose levels
Resistant starch is beneficial, but how does it help in controlling glucose levels? Will it make it possible for a diabetic to enjoy eating rice? Isn’t that something that is contraindicated from the day you are diagnosed with diabetes? Let’s find out!
Well, resistant starch, because of its complex structure, delays the gastric emptying time, preventing insulin spikes and postprandial hyperglycemia. Since resistant starch has a low glycemic index, it can be substituted for conventional starches like maize, wheat, rice, potato and tapioca in foods. RS contributes to the total carbohydrate (CHO) in a meal, but not the available CHO thereby causing energy dilution.
RS has also been shown to reduce the glycemic response to a forthcoming meal, a phenomenon known as the “second meal effect” which is of prime importance in managing diabetes.
June Zhou et al. studied the association between resistant starch and the regulation of Incretins like GIP, and GLP. They are the hormones that regulate the amount of insulin to be secreted by the pancreas and are secreted by the enteroendocrine cells of the GI tract. Research has shown that chronic consumption of RS upregulates the GLP-1 synthesis, which can improve glycemic control and insulin sensitivity in diabetic individuals and helping maintain plasma glucose homeostasis.
Resistant starch has been shown to have probiotic effects as well. As they reach the colon, the local resident bacteria (good gut bacteria) ferment them to liberate SCFA (Short chain fatty acids). These SCFAs are nothing but the food for healthy bacteria which facilitates their growth.
The research found that the participants with insulin resistance who consumed supplements with 66 gram of resistant starch (type 2) per day for 2 weeks, improved their insulin sensitivity and their ratio of ‘good’ bowel bacteria also increased.
How to increase resistant starch in foods?
There are some ways in which we can increase the amount of resistant starch in the foods. This greatly depends upon how the food is prepared, cooked and whether it is reheated.
One such method is retrogradation, a process of cooking and then cooling down the food which enables the molecules of cooked starch to get recrystallised in an aligned manner. For example, by cooking rice in water, the starch molecules gelatinize. The rice grain swells by absorbing water. After refrigerating it, the water molecules seep out of them and starch molecules rearrange into a crystalline structure and can no longer be broken by the enzymes thus can simply escape the digestion.
Retrogradation thus can be done on various starchy foods such as rice, potato, legumes, cereals and peas by simply cooking followed by cooling.
Resistant starch is the type of carbohydrate that escapes digestion in the maximum part of our GI tract. Starchy foods should be retrograded (cooked and then cooled at low temperatures) so as to reduce their digestibility across most of the GI tract. This helps avoid insulin spikes, and postprandial hyperglycemia, improving insulin sensitivity and thereby aiding in the management of diabetes. In this way, a diabetic individual can freely enjoy eating this modified version of rice without any stress. A positive correlation was also seen between the consumption of Resistant Starch and the growth of a healthy gut microbiome in individuals with Type 2 diabetes mellitus.