Sweet potatoes are known to be superfoods in their own right, but a new study suggests that consuming waste water from sweet potatoes cooking may offer up a trimmer waistline. Researchers found that the starchy waste left behind in the water after cooking made mice slimmer.
The mice in the study consumed high-fat diets and yet had lower body weight after one month of consuming the waste water from sweet potatoes. The researchers suggest that the peptide found in the waste water could hold a secret of fat digestion, but whether humans would experience the same effects remains unknown for now
Lead investigator Dr. Koji Ishiguro explained, “We throw out huge volumes of wastewater that contains sweet potato proteins – we hypothesized that these could affect body weight, fat tissue, and other factors. Finding alternative uses for the sweet potato proteins in wastewater could be good for the environment and industry, and also potentially for health.”
Mice who consumed a high-fat diet were fed sweet potato peptide either in a high concentration or low concentration. After 28 days, body weight was measured in both groups, along with cholesterol and triglyceride levels. Mice given high concentrations of sweet potato peptide had lower body weight and liver mass, along with lower cholesterol and triglycerides. Furthermore, they had higher levels of hunger-controlling hormones.
Dr. Ishiguro continued, “We were surprised that SPP [sweet potato peptide] reduced the levels of fat molecules in the mice and that it appears to be involved controlling appetite suppression molecules… These results are very promising, providing new options for using this wastewater instead of discarding it. We hope SPP is used for the functional food material in future.”