Food is essential—it provides vital nutrients for survival, and helps the body function and stay healthy. Food consists of macronutrients including protein, carbohydrate and fat that not only offer calories to fuel the body and give it energy but play specific roles in maintaining health, it also contains micronutrients that can be divided into four groups — water-soluble vitamins, fat-soluble vitamins, macrominerals and trace minerals. Good nutrition is an important part of leading a healthy lifestyle. Combined with physical activity, your diet can help you to reach and maintain a healthy weight, reduce your risk of chronic diseases (like heart disease and cancer), and promote your overall health.