Winter brings hot chocolate, holidays and some really stubborn seasonal myths.To clear the air, we talked to Dr. Rachel Vreeman, an assistant professor of pediatrics at the Indiana University School of Medicine and co-author of Don’t Cross Your Eyes … They’ll Get Stuck That Way!: And 75 Other Health Myths Debunked.Myth No. 1: Poinsettias are extremely toxic.You don’t want to let the kids munch on the poinsettia — or any other household plant that’s not intended for human consumption. But Vreeman says that the data don’t show any really serious problems with poinsettia consumption. (A 1996 study of more than 22,000 poinsettia exposures reported to poison control centers found that most people had no symptoms and there were no “major effects” such as life-threatening reactions.)Rats, Vreeman says, have to eat enormous quantities of poinsettia — many times their body weight — before they even show signs of feeling sick. “I don’t think poinsettias taste very good from what people report, but they are not toxic,” Vreeman says.Myth No. 2: The suicide rate spikes over the holidays.“If you look at the data, you realize it’s just not true,” Vreeman says. So why do we continue to believe in the seasonal suicide spike? The holidays really are difficult for many people, and the emphasis on togetherness makes us feel sorry for those we think are alone, Vreeman says. “I think [the myth] has just enough of a sense of truth to it that we just believe it and hold onto it.”The suicide rate for the general population is 12.4 suicides per 100,000 people, according to the Centers for Disease Control and Prevention, which says that the suicide rate peaks in spring and fall.November, December and January typically have the lowest daily suicide rates, according to the Annenberg Public Policy Center at the University of Pennsylvania.Myth No. 3: Sugar makes kids hyper.“Sugar has actually been studied in children in randomized controlled trials better than many of the drugs we use in children for medication purposes,” Vreeman says. “And I think it’s been studied over and over again because scientists themselves cannot believe that sugar isn’t making children hyper.”The kids may indeed be keyed up over the holidays, she says, but don’t blame the cookies.Myth No. 4: Cold weather makes you sick.“People have studied this in so many different ways — going so far as studying all the people on an island in the Arctic Sea to see if they’re getting more sick than people in warmer places,” Vreeman says. “Scientists have done tests where they’ve put cold viruses right into people’s noses to see if they get sick more easily in cold conditions.” Cold, she says, is not the culprit.Myth No. 5: You lose most of your body heat through your head.“You lose heat from whatever part of your body is exposed,” says Vreeman. “It has to do with what is uncovered and its surface area.”In other words, there’s nothing special about your head. If you leave another body part with a similar surface area exposed, you’ll lose just as much heat.