Your body needs foods from all of the main food groups in order to function correctly and feel healthy and energetic. It is important not to cut out any food group completely, or to restrict it unnecessarily.

Protein

The body uses protein to build and repair all protein components of the body. This includes muscle, blood, organs, nerves, skin, hair and the brain. It also helps to keep you feeling full for a longer period of time.

Some good sources of protein include:

• lean meats and poultry
• low-fat dairy products
• soy beans
• nuts
• lentils
• eggs

Carbohydrates

Carbohydrates provide your body with the energy it needs for normal functioning, such as maintaining your breathing and heartbeat, and for everyday activities such as walking and general movement.

Some good sources of carbohydrates are:

• whole-grain breads
• high-fiber cereals
• potatoes
• fruits
• vegetables
• brown rice
• corn
• legumes

Fats

Fats provide a concentrated energy source for the body, which is essential for good health. They also help absorb and transport fat-soluble vitamins throughout the body.

However, not all fats are equal. For example, saturated and trans fats are bad for your body and are therefore best avoided or limited. Most Americans eat too much of these bad fats. Some sources of these unhealthy fats are cream, butter, and processed foods which have "partially hydrogenated vegetable oils" or "hydrogenated oils" listed in the ingredients section of the pack. 

Sources of healthy fats include:

• Avocados
• Oily fish, such as salmon, tuna and sardines
• Olive and canola oils
• Raw nuts