Long term exposure to stress can affect the function of all you body parts. Stress elevates different hormones and worsens your immune function making it harder to fight diseases and infections. It can also lead to heart disease, diabetes, depression and more. But its not only stress that can do this. What you eat can affect just about everything too, including your mental health. Different foods affect the bacteria in your microbiome which affects your hormones as well, leading to many other problems.