And no, we’re not talking about the skin.
We already know sweet potato to be a bit of a superfood. Fewer in calories than a regular potato, not only have these golden gems been linked to cancer prevention, but they are also a fabulous source of Vitamin A for healthy eyes, Vitamin B for energy and immunity and contain antioxidants that carry anti-aging properties.
Typically, we bake, mash or fry it, but a new study suggests that, in order to get the most nutrition out of the vegetable, we should perhaps be thinking outside the box in our consumption methods.
A team of researchers, led by Dr. Koji Ishiguro from the National Agriculture and Food Research Organization in Japan, began looking into ways to reduce the wastewater produced upon boiling sweet potatoes on an industrial scale.
The International Potato Center says that across the world, more than 105 million tonnes of the vegetable is being produced every year (making it the fifth most important crop), with their high starch content to be a valuable ingredient in noodles, confectionary, bread, flour and more.
In Japan alone, 15 percent of sweet potato is used to for starch-derived products, distilled spirits and processed foods, which naturally results in huge amounts of wastewater then ends up in rivers and oceans.
To avoid the environmental repercussions of this waste, the scientists set out on a health mission.
"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,” says Dr. Koji Ishiguro.
“Finding alternative uses for the sweet potato proteins in wastewater could be good for the environment and industry, and also potentially for health.”
The team fed three groups of mice high-fat diets – one group’s regime included a high concentration of the sweet potato peptide protein (SPP), while another was given a lower dosage.
After a month, the researchers collated the rodent’s data, taking to account their liver mass, fatty tissue, fat cholesterol levels and triglyceride levels.
They also measured levels of leptin, which controls hunger, and adiponectin, which regulates metabolic syndrome.
From these results, Dr. Ishiguro could see that the mice who had been given SPP has a significantly lower body weight and liver mass, as well as lower cholesterol and triglycerides.
And as they SPP groups also had higher levels of the hunger and lipid-controlling hormones, the team was able to speculate that SPP had the ability to act as an appetite suppressant.
"We were surprised that SPP reduced the levels of fat molecules in the mice and that it appears to be involved controlling appetite suppression molecules," said Dr. Ishiguro.
"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."
More research is yet to be conducted on the results of SPP in the human diet, so until then, feel free to help yourself to some of this pumpkin and sweet potato pie from our friends over at Food To Love!