The relentless accumulation of excessive body fat in some children and adults may be at least partly due to viral infection. A study done by Richard L. Atkinson found that about 30% of obese individuals had signs of having been infected at least once by adenovirus-36 (AD-36); by comparison, a mere 11% of individuals within their normal weight ranges tested positive for the presence of AD-36 antibodies.
Another study titled “Adenovirus 36 and Obesity in Children and Adolescents” was published by the American Academy of Pediatrics. In the study, 124 children were examined and in those children, 46% were non-obese and the remaining 54% were obese. In those 124 children, 19 (15%) of them were AD-36 positive. Out of the 19, 15 (78%) were obese children. The study showed that majority of children with AD-36 positive were obese. Children exhibiting AD-36 positive were heavier than AD-36 negative children by about 50 pounds. In the obese group, AD-36 positive children were about 35 pounds heavier than AD-36 negative children.
Adenoviruses are commonly the cause of a variety of respiratory, gastrointestinal and other infections in humans. In laboratory experiments, monkeys deliberately infected with adenovirus-36 have gained weight. Accumulating evidence suggests that an AD-36 infection can trigger immature fat cells, which are called preadipocytes, into developing more rapidly and into increasing their numbers beyond normal levels. Researchers suspect a specific gene in the virus E4 ORF-1 may be the culprit. Blocking this particular gene has been found to prevent the deleterious effects on immature fat cells.
Childhood obesity has become an epidemic, deeply concerning health experts. Once obese, children mostly retain the excess body fat throughout adulthood. The possibility that viruses may hold considerable responsibility for uncontrolled weight gain leads to the tantalizing prospect of effective pharmaceutical treatments for combating obesity. However, AD-36 is the only virus thus far to be connected to obesity in humans, and the disease vectors and metabolic effects remain poorly understood. Not all medical experts are convinced, preferring instead to await the results of more research.