Diet is often referred to as some dietary regimen for losing weight. However, diet simply means what food we eat in the course of a 24-hour, one week, or one month, etc. period.
A good diet is a nutritional lifestyle that promotes good health. A good diet must include several food groups because one single group cannot provide everything a human needs for good health.
This Medical News Today information article provides details on when we should eat, what defines healthy eating, World Health Organization (WHO) recommendations on healthy eating, what the Healthy Eating Index (HEI) is, the consequences of unhealthy eating, and how plant-based diets protect from chronic diseases.