Science Update

Study demonstrates the benefits of green banana resistant starch in patients with insulin resistance

The consumption of green banana products has recently increased due to their nutritional and physiological benefits. Green bananas are a great source of fiber and resistant starch, as well as vitamins A, C, B6, potassium, magnesium, phosphorus, and zinc.

Previous research has shown a variety of health benefits from resistant starch, including increased insulin sensitivity, preventing obesity, lowering cholesterol, preventing constipation, and producing short chain fatty acids in the gut.

In a new review published in Nutrients, which consisted of 18 articles, researchers investigated the potential benefits of green banana consumption. Most of the health benefits of green banana were associated with improvements in gastrointestinal health, dysglycemia, weight loss, and complications secondary to diabetes. As a result, studies demonstrated an improvement of both diarrhea and constipation. In individuals with type 2 diabetes, there was a reduction in body weight and an increase in insulin sensitivity. In addition, body weight, body composition, and lipid and inflammatory biomarkers were all improved in overweight individuals.

A high fiber diet leads to the production of short chain fatty acids (SCFAs) in the gastrointestinal tract. These play an essential role in T regulatory cell activation, which regulates the intestinal immune system.

Resistant starch includes all starch and starch degradation products that bypass digestion in the small intestine because they are physically inaccessible in the food matrix (RS1), within starch granules (RS2) or because they are present as retrograded starch (RS3), which is produced during food manufacturing and preparation. Starch can also be chemically modified (RS4) to make it resistant to enzymatic digestion.

Green banana is considered RS2, as it is indigestible due to the high amylose content in its raw form. This plays an important role as a prebiotic and is responsible for some of its physiological properties. Prebiotics impair the uptake of dietary cholesterol and reduce bile acid reabsorption. They also increase bacterial fermentation in the colon, which affects gut barrier function and cholesterol metabolism, regulates GLP-1, and reduces translocation of lipopolysaccharides.

Resistant starch should be considered for patients with obesity, insulin resistance, dyslipidemia, and metabolic syndrome. It can also be a great substitute to regular starch in baked goods, which lowers the caloric density and glycemic index of food products.

By Michael Jurgelewicz, DC, DACBN, DCBCN, CNS

Source: Falcomer AL, Riquette RFR, et al. Health Benefits of Green Banana Consumption: A Systemic Review. Nutrients. 2019 May 29; 11(6).