Hostility* is a psychological concept that is different to - but that overlaps to some extent with - the everyday use of the word. Previous studies have linked hostility to heart disease, high blood pressure and a greater overall risk of death and new research has suggested that it is also linked to weight gain as well. A study, carried out by French researchers, of 6,484 men and women in the U.K. measured the participants' hostility at the start of the study and tracked their weight over the following 19 years. At the start of the study both men and women with higher hostility levels weighed more. The participants' weight rose over the course of the study but while the relationship between weight and hostility remained constant in women hostility was found to accelerate weight gain in men. This could be because hostile people might be less likely to follow healthy-eating and exercise advice or because they are more likely to be depressed which, in itself, can lead to weight gain.
*for a definition of the psychological term hostility see