阅读下面材料，在空白处填入适当的内容（1个单词）或括号内单词的正确形式。
Scientists have discovered that___(stay) in the cold could help us lose weight. Researchers at the University of California found that exposure to the cold increases levels of a protein that helps form brown fat-the type of fat that produces heat and keeps us warm. Brown fat burns energy, _____ helps us lose weight. White fat stores extra energy, which results    weight gain. The researchers said that because air conditioning and heating give us constant, ___(comfort) temperatures, our body's need for brown fat has decreased. They found that:“Outdoor workers in northern Finland who_____(expose) to cold temperature have___ significant amount of brown fat when_____(compare) to same - aged indoor workers.”
The research was conducted on two different control groups of mice.__ __group was injected with the protein that helps create brown fat. This group later gained 30% less weight after both groups were fed high - fat diets. The researchers say this could be good news in the fight against obesity. People who are obese have _____(low) levels of brown fat than thinner people. Head researcher Hei Sook Sul said: "This protein could become an important target for research into the treatment and prevention of obesity and obesity - related diseases.” She added: "If you can somehow increase levels of this protein, you could____(possible) lose more weight even if eating the same amount of food.”