ers went through earlier studies and reports on both energy drinks and sports drinks, which don't contain any stimulants. They note that energy drinks contain a jumble of ingredients -- including vitamins and herbal extracts -- with possible side effects that aren't always well understood. While there aren't many documented cases of harm directly linked to the beverages, stimulants can disturb the heart's rhythm and may lead to seizures in very rare cases, Benjamin said. Recently, she saw a 15-year-old boy with attention deficit hyperactivity disorder who came into the hospital with a seizure after having drunk two 24-ounce bottles of Mountain Dew, a soft drink that contains caffeine. The boy was already taking stimulant ADHD medication, and the extra caffeine in principle might have pushed him over the edge, according to Benjamin. "You just never know," she said. "It's definitely a concern." Earlier this year, Pediatrics published another review of the literature on energy drinks. In it, Florida pediatricians described cases of seizures, delusions, heart problems and kidney or liver damage in people who had drunk one or more non-alcoholic energy drinks -- including brands like Red Bull, Spike Shooter and Redline. While they acknowledged that such cases are very rare, and can't be conclusively linked to the drinks, they urged caution, especially in kids with medical conditions (see Reuters story of February 14, 2011). U.S. sales of non-alcoholic energy drinks are expected to hit $9 billion this year, with children and young adults accounting for half the market. Manufacturers claim their products will enhance bothry housing will be made available for up to 18 months. Some people along the Gulf Coast still live in FEMA trailers nearly six years after Hurricane Katrina. Another FEMA spokesman, Bob Josephson, said the agency will consider bringing trailers to Joplin if enough existing housing isn't available. He said every effort will be made to find existing rental units closest to Joplin and that many residents may simply choose to find their own housing options. People who lived in the 8,000 structures smashed in the storm have scattered to the homes of friends and relatives or camped out in emergency shelters in the city. Some may leave town -- New Orleans lost nearly one-third of its population after Katrina. Penny Musgraves is happy -- and almost surprised -- to be alive. But for Musgraves, whose low-income townhouse was ripped away above her head as she protected her cowering 6-year-old daughter, the joy of surviving is beginning to give way to confusion and anxiety about the future. "I'm kind of scared," said the 45-year-old mother, who is unemployed and currently living with her daughter at the Red Cross shelter set up at Missouri Southern State University. "There isn't much low-income housing. I can't rent a place. I don't know what I'm going to do." While many of the survivors had insurance, it could be months, if not years, before they can rebuild. Removing the millions of tons of debris and remaking the city's destroyed infrastructure will likely take well into the summer if not longer. Rebuilding homes can't start until that work is finished. For low-income residents, the Housing Authority of Joplin provides some housing. But it was not known how many, if any, of the homeless it can accommodate. Recent history suggests many people won't be able to wait for the answers to emerge or for the rebuilding to be completed. The current population could drop substantially. New Orleans lost 29 percent of its population after Hurricane Katrina as residents left and settled elsewhere. Greensburg, Kan., which was leveled by a tornado in 2007, lost about half its population even though the town was rebuilt. It dropped from 1,574 before the tornado to 777 in 2010. At the Red Cross shelter, 150 people seemed grateful for the cot, warm food and donations of clothing. Many were trying to figure out where to go next. Ask 64-year-old William Whittenback where his home is, and he has a quick answer. "Plum off the map," the retiree said. Whittenback and his 67-year-old wife, Lorna, narrowly made it through the tornado. The roof of the home they've lived in for 15 years collapsed, leaving Lorna with a massive gash on her forehead and her cheeks black and blue. Every house in their neighborhood was a total loss. The coup