Resistant Starch: Discover Its Properties and Benefits

Is it true that cooling potatoes and sweet potatoes after cooking makes them less fattening? And what happens to their health impact when starch turns into sugar?

Potatoes are primarily made up of water (75-80%), starch (15-20%), and small amounts of protein and fibre. When we cook potatoes or other tubers, the starch inside them gelatinises: it absorbs water, swells, and loses its crystalline structure. This process makes the starch easier to digest and absorb in the intestine as glucose, a simple sugar that provides essential energy for the body.

However, if you cool cooked potatoes, a portion of the starch reorganises due to the cold (a process called retrogradation), forming a more compact structure that is harder for the body to metabolise. This restructured starch is known as resistant starch.

What Is Resistant Starch and How Does It Work?

Resistant starch is not digested in the small intestine. Instead, it travels to the colon, where it acts like dietary fibre, serving as a prebiotic. It promotes the growth of beneficial bacteria, such as Bifidobacterium and Lactobacillus. When these bacteria ferment resistant starch, they produce butyrate, a short-chain fatty acid with remarkable health benefits.

Benefits of Resistant Starch

1. Gut health: Butyrate protects colon cells, reduces the risk of inflammatory bowel diseases, and supports the intestinal mucosa.
2. Healthy microbiome: It fosters the growth of good bacteria and maintains an acidic pH in the colon, inhibiting harmful bacteria.
3. Weight management: Resistant starch increases feelings of fullness, helping to reduce snacking.
4. Improved metabolism: It enhances insulin sensitivity, regulates blood sugar spikes, and prevents excessive fat storage.

How to Increase Resistant Starch in Your Diet

To maximise the amount of resistant starch in your food, cook potatoes thoroughly (boiling is ideal) and cool them for at least 4 hours before eating. This simple process transforms digestible starch into resistant starch, boosting its health benefits.

In summary, resistant starch not only supports a healthy gut microbiome but also aids in weight control, improves metabolism, and lowers the risk of metabolic diseases. Adding resistant starch to your diet is a simple yet effective way to enhance your overall health.