A well-balanced diet provides all of these: 

The energy you need to keep you active throughout the day

Nutrients you need for growth and repair, helping you to stay strong and healthy and help to prevent diet-related illness.

Keeping active and eating a healthy balanced diet can also help you to maintain a healthy weight.

Deficiencies in some key nutrients such as vitamin A, B, C and E, and zinc, iron and selenium - can weaken parts of your immune system.

Strong bones and teeth

 A diet rich in calcium keeps your teeth and bones strong and can help to slow bone loss(osteoporosis) associated with getting older. Calcium is usually associated with dairy products, but you can also get calcium by eating sardines, pilchards or tinned salmon (with bones), dark green vegetables such as kale and broccoli, calcium-fortified foods such as soya products, fruit juices and cereals. As vitamin D helps your body absorb calcium, make sure you get outside (your body gets vitamin D from the sun) and have plenty of foods containing vitamin D in your diet such as oily fish and fortified cereals.