Consumption of cooled rice that contains resistant starch can help aid weight loss.
Rice mainly contains two types of starch: digestible and resistant. The digestible starches can be quickly broken down and turn into glucose and would store as fat. The resistant starch cannot be digested, and they pass through the large intestine. However, scientists have developed a method of cooking rice that changes the digestible starch to resistant starch. This method could cut the number of calories absorbed by the body, reducing obesity rates.
According to PubMed Central, one of the studies examined the effects of retrograded rice on body weight gain, gut functions, and hypolipidemic actions in rats. Retrogradation is a reaction that takes place when the amylose and amylopectin chains in cooked, gelatinized starch realign themselves as the cooked starch cools.
Retrograded rice produced by repeated heating and cooling cycles contained significantly higher resistant starch amounts than ordinarily prepared rice. Sprague-Dawley rats were fed either normal rice powder or retrograded rice powder, and weight gain and liver weight were significantly lower in the retrograded rice group.
Meanwhile, the new international study presented at the 2019 European Congress on Obesity explained that obesity levels are "substantially lower" in countries where rice consumption is high (150 grams per day) than countries with lower average rice intake. The analysis found that obesity levels, smoking rates, and overall health expenditure were significantly lower in countries that consumed lots of rice. Also, lead researcher Tomoko Imai from Doshisha Women's College of Liberal Arts in Japan said that "eating rice seems to protect against weight gain."