Obesity makes it harder for some people to fight infections and heal wounds, according to a Yahoo! News Article dated December 12, 2007. This may be due to the tendency of obese people to have weakened immune responses.

In a Boston University Research study, researchers tied silk threads laced with gum disease to the teeth of obese mice and mice of regular weight to compare the animals' response to the infection. It was discovered that the obese mice were more susceptible to the disease and were less able to fight the gum infection.

The white blood cells of the obese mice, which are mainly responsible for fighting infections, had lower levels of a signaling molecule and altered genes that fight inflammation. The study was not conclusive on why this connection exists. One theory is that constant exposure to food alters a signaling pathway that controls a protein, NF-kB, which, in turn, alters the ability of a person to fight infection.

The study also concludes that this process works the same in humans. In general, obese people are more likely to have gum disease as a result of a lower immune response to fight the infection and stop the inflammation properly.

The researchers also propose that new treatments should be developed for obese people that specifically target a weakened immune response system.