A passenger waits at Heathrow airport in London, August 12, 2006. Elderly people who are obese appear to have a lower risk of falling ill with tuberculosis compared to those who are underweight or of average weight, according to an extensive geriatric study in Hong Kong. (Toby Melville/Reuters)Reuters - Elderly people who are corpulent appear to father a lower imperil of falling ill with tuberculosis compared to those who are underweight or of customarily weight, according to an far-ranging geriatric retreat in Hong Kong.