The Fat Virus

New evidence has emerged that suggests that obesity may not be entirely the result of unfavourable eating habits and low physical activity levels. A recent study by a group at the University of Wisconsin, published in the International Journal of Obesity has reported that a virus may be a contributing factor to obesity.

The researchers inoculated chickens and mice with the virus, known as AD-36, resulting in excessive fat gain. Adiposity in the affected animals increased (in particular visceral fat, total fat and body weight), however serum cholesterol and triglyceride levels decreased. There was no evidence of damage to those parts of the brain that control energy balance in affected chickens; however more studies in mammals where much more is known about control of energy balance would be helpful.

Obese people may have antibodies to the virus as demonstrated in a sample of obese and lean people from New York. Antibodies were found in 20-60% of obese people compared to only 5% of lean people, and were also demonstrated in the chickens and mice used in this study.

The virus seems to work by affecting part of the brain that controls energy expenditure, however this has not yet been established. The jury is still out as to whether this virus may be a contributing factor to obesity as further studies are needed to ascertain it's role in mammals, in particular humans, and the means by which it is contracted and operates in the body.

Therefore, eating a nutritious and healthy diet, combined with regular physical activity remains the best way to avoid obesity or to maintain or reduce weight.

References

• Editorial. Is obesity contagious? International Journal of Obesity
  
• On the trail of the fat virus? Choice Health Reader, September 2000.

Last Updated: April 5, 2001