A British tabloid reported that Kate Middleton has to lose weight since the announcement pertunangannua with Prince William in November last.
Although not confirmed, the British newspaper said the queen's future is losing two dress sizes, originally from the U.S. size 6 to size 2.
"Basically, this could mean losing weight about 4.5 kg to 6 kg or more, and not just body fat," said Leslie Bonci, director of sports nutrition University of Pittsburgh Medical Center.
According to Bonci, the loss or lose weight in that amount (for her body size) are not healthy anyway.
But there are circles who claim that weight loss Kate is still relatively healthy.
"If within a period of 5 months she was losing weight 9 kg (20 pounds), meant he was losing weight 1 pound (O, 45 kg) every 7.5 days. The recommendation is safe to lose weight is not more than 0.45 kg (1 pound) per week. So, losing weight 9 kg in 5 months is still in accordance with the guidelines for healthy, "said Carla Wolper, obesity researcher at St. Luke's Hospital and assistant professor of Eating Disorders Research Center at Columbia University Medical Center, New York.
Besides mentioning her weight loss is unhealthy, Bonci also said that the ratio between height and weight, relatively thin Kate.
"Rumors say height 5 feet 10 inches (177.8 cm) and weight 120 pounds (54.4 kg). Weight loss that he put 80 percent of ideal body weight, or certainly thin," says Bonci.
Observers of the royal family believe that stress is a partial cause of weight loss Kate.
"Recently in each successive appearance since she got engaged, he looked thin and getting thinner. I imagine he probably could not eat," said Duncan Larcombe.
But nutritionists in the United States said this stress may be a factor, but he believes there are other reasons behind her weight loss.
"This seems to be a voluntary case, go-on-a diet, a quick way to lose weight," said Dr. David Katz, director of Yale University's Prevention Research Center in New Haven, Conn.
But for some experts, it's all part of a pre-marriage rituals are very normal.