What is resistant starch?
Resistant starch is a kind of starch that is not digested in the small intestine like other starches, hence its name. Instead it is digested by the gut bacteria in our large intestine and ‘resists’ digestion as such. Due to this fact it does not spike blood sugar or insulin. Our gut bacteria metabolise resistant starch and create molecules inside the body that are beneficial to health. Resistant starch enhances metabolism, helps balance blood sugar and optimises our gut flora to promote weight loss.
Resistant starch is made by cooking, cooling and then eating starches like potato or rice without reheating them, or reheating them to less than 130 degrees celsius. After the cooked starch is cooled, the starch (amylose) molecules rearrange structures (crystalize) and become less digestible. This process is called retrogradation.
Resistant starch is in fact a prebiotic which feeds our gut bacteria like psyllium, potatoes, green bananas and chicory. More on prebiotics here. It encourages a greater diversity of bacteria in the gut which is linked to good health. Beneficial gut bacteria produce short chain fatty acids like butyrate which reduce inflammation, protect the gut and help us sleep better, article on that here.
The fact that resistant starch doesn’t spike insulin should allow us to sleep deeper for longer. Deep sleep seems to be the hardest type of sleep for people to maintain as we get older. The less deep sleep you have the more of a negative effect on cognitive function it will have, and it may even lead to Alzheimer’s later in life. Insulin degrading enzyme is also responsible for breaking down beta-amyloid plaque in the brain, a factor in Alzheimer’s disease. If you use it all on breaking down insulin from you last meal before bed, the less likely it is that it will break down beta-amyloid. Studies have shown resistant starch to optimize cholesterol, triglycerides whilst decreasing fat mass.
So how can we incorporate resistant starch into our diets?
Resistant starch can be mixed into water, almond milk, smoothies and yogurt. You can also eat it in the form of prebiotic-rich foods such as bananas, onions, garlic, Jerusalem artichokes and leeks or cook and cool your starches such as potato, legumes (soaked or sprouted) and rice before eating, overnight cooling/chilling is preferable or for 1-2 days. Steaming, pressure cooking and stir-frying rice produce higher levels of resistant starch than boiling.
If you add resistant starch to your diet, do take it slowly because this stuff will change your gut bacteria. Start with ¼ teaspoon daily if you’re going for unmodified potato starch. Expect some gas and boating to start but this should pass. If it continues, you may have a gut issue that needs to be fixed so go see your NT!