Study Shows Plant Protein Shake Better for Blood Sugar Control than Dairy-Based Whey

Full publication – Nutrients 2021

A study published June 23, 2021 in Nutrients aimed to look at the short-term effects on glycemic indices, gut hormones and subjective appetite ratings of two plant proteins (potato or rice) compared to an animal/dairy-based whey protein.

Nine healthy male volunteers completed the single-blind, triple crossover study. In other words, on three different visits participants randomly received one of three different protein shakes without knowing which protein they were receiving, followed by a 1-week washout period between visits. Protein shakes were matched for protein (49g), calories and carbohydrates and prepared using Oryzatein® rice protein isolate, potato protein isolate or whey protein isolate mixed with a standard orange juice.

Participants had to consume the shake within 5 minutes and following a 12 hour overnight fast. Glyceamic indices (blood sugar, insulin, insulin resistance), gut hormones (GLP-1, PYY, ghrelin) were measured at baseline (before shake consumption) and then 30, 60, 120 and 180 minutes after shake consumption. Subjective palatability was measured during consumption of the shake and satiety was measured at baseline and every half hour during a 3-hour period after consumption.

Appetite and satiety perceptions were very similar between all proteins, with no significant differences observed despite a greater GLP-1 response shown after drinking the whey shake. GLP-1 is a key appetite regulating hormone.

The researchers report that both insulin and glucose responses were more substantial with whey protein than both plant-based proteins. On the other hand, plant-based proteins had smaller responses with a significant difference observed for insulin between potato and whey proteins.

As such the researchers concluded that plant-based proteins appears to better control blood glucose compared to whey protein.