Regular Exercise: You should be aiming to be as active as you can be, not just by jogging once a week, but by minimizing the amount of time you spend sedentary and by regularly engaging in both leisurely exercise and more intense exercise.
A Healthy Diet: It is a well-known fact that diet plays a major role in how the body fights infection. A diet which consists of too many processed foods, unhealthy fats and sugars leads to poor health, simple as that. Being deficient in the minerals and vitamins found in fruits and vegetables, will reduce your body’s ability to repair, grow and defend itself which can lead to feelings of lethargy and mood swings.
Get enough sleep: Everybody has different needs when it comes to a good night’s sleep. Some seem to be able to survive perfectly well on five hours, while others need 8-9 to get through the day. Most people should aim to get between 7-9 hours per night, no more, no less.
Limit stress: There is a close connection between the mind and body. Emotional feelings of stress, upset and anxiety can manifest in physical symptoms. Some studies have suggested that prolonged feeling of stress, which increases levels of cortisol in the body, can lower immune system response.