The clinical nutritionist and doctor of natural medicine and is out to prove that food should take center stage when it comes to treating health issues. Jen Selter has received her share of criticism for dishing out suspect fitness advice.

The authors of the study, published on Wednesday in The Lancet, noted that unhappiness was strongly linked to poor health and increased risk of death. But after adjusting for poor health and the lifestyle factors that could lead to illness, such as smoking and inactivity, the researchers found virtually no difference in the mortality rate between happy and unhappy individuals.