energy you need to keep 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, such as some cancers 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.
More about vitamins, minerals and nutrients
Type 2 diabetes:
Maintaining a healthy weight and eating a balanced diet that's low in saturated fat and high in fibre found in whole grains can help to reduce your risk of developing type 2 diabetes.
More about type 2 diabetes
A healthy diet rich in fruits, vegetables, whole grains and low-fat dairy can help to reduce your risk of heart disease by maintaining blood pressure and cholesterol levels.
High blood pressure and cholesterol can be a symptom of too much salt and saturated fats in your diet.
Eating a portion of oily fish - such as salmon and trout - each week can also help to lower your risk of developing heart disease. The high levels of omega-3 fatty acids in oily fish are good for heart health.
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.
More about vitamin D
How to manage your weight:
Eating a healthy diet that includes lots of fruit, vegetables, whole grains and a moderate amount of unsaturated fats, meat and dairy can help you maintain a steady weight. Having a good variety of these foods every day leaves less room for foods that are high in fat and sugar - a leading cause of weight gain.
Together with exercise, eating a healthy diet in the right proportions can also help you lose weight, lower your cholesterol levels and blood pressure and decrease your risk of type 2 diabetes.