Kefir may be a beneficial post-exercise beverage for cancer survivors. It means that cancer survivors can enjoy the nutritional support that milk provides without the potential for significant stomach upset, report researchers in the Journal of Dairy Science®. Regular exercise plays an important role in improving cardiorespiratory fitness, muscular strength, and feelings of fatigue in cancer survivors during and after treatment. However, many people with cancer experience digestive upset due to treatment and may be wary of incorporating dairy products into their diet to help support their recovery.

Kefir is a fermented milk product that is a good source of protein, health-promoting bacteria, and carbohydrates. Documented health effects attributed to the consumption of kefir include improved lactose use, anticarcinogenic activity, control of intestinal infections, and improved milk flavor, and nutritional quality.

Investigators explored cancer survivors' attitudes about consumption and acceptance of a kefir recovery beverage made from cultured milk, whole fruit, natural sweeteners, and other natural ingredients. A kefir beverage that met the American College of Sports Medicine guidelines for recommended nutrition after endurance and resistance exercise was developed and manufactured at the Louisiana State University Creamery. It was made by inoculating and fermenting milk with kefir grains. The kefir was then mixed with a fruit base and given to 52 cancer survivors following an exercise session.

Participants evaluated the acceptability of the beverage samples (overall appearance, aroma, taste, mouth-feel, and overall liking) using a nine-point scale, and they evaluated the smoothness using a three-category just-about-right scale (not enough, just about right, and too much). They also expressed their physical and psychological feelings about the beverage using a five-point scale (ranging from 1 = not at all to 5 = extremely) and indicated their intent to purchase the drink.

Following the initial test, the health benefits of kefir were explained and participants sampled the product a second time, answering the same questions related to overall liking, feeling, and intent to purchase.

Participants showed a high intent to purchase both before and after they learned about the health benefits, but the beverage scored significantly higher for overall liking after the health benefits were explained.

"Kefir may be a great way for cancer survivors to enjoy a post-exercise dairy drink in the future," commented lead investigator Laura K. Stewart, PhD, Associate Professor at the University of Northern Colorado, School of Sport and Exercise Science. "The beverage received high scores overall and, except for an improvement in overall liking, we observed no significant differences in physical and psychological feelings before and after participants learned that it contained kefir and had potential health benefits."

O'Brien K, Boeneke C, Prinyawiwatkul W, Lisano J, Shackelford D, Reeves K, Christensen M, Hayward R, Ordonez KC, Stewart LK.
Short communication: Sensory analysis of a kefir product designed for active cancer survivors.
J Dairy Sci. 2017 Jun;100(6):4349-4353. doi: 10.3168/jds.2016-12320.