Why Do I need to eat?

Your body's trillions of tiny cells work day and night to keep you alive. To keep going they need energy, which comes from the food you eat. Food also provides the building materials that your cells use to make you grow, but first, your body must digest the food, releasing the simple nutrients that your body can use.

10 Things your liver is doing right now

• Processing digested food.

• Controlling levels of glucose (sugar) in your blood.

• storing and transporting fats.

• Processing amino acids (protein building blocks) and making proteins.

• Making green bile, which flows into the small intestine to help digest fats.

• Storing vitamins A, B12, D, E, and K.

• Removing hormones (chemical messengers) from the blood once they've done their job.

• Removing and breaking down drugs and poisons.

• Removing bacteria (germs).

• Removing worn-out red blood cells.

Nutrients you need from food

What?	Why?	Which foods?
carbohydrates	to provide energy	meat, fish, beans
proteins	growth and repair	meat, fish, beans
fats	energy, insulation	dairy foods, plant oils, meat, fish
vitamins	to help cells work	fruit, vegetables, eggs, meat, fish
minerals	to help cells work	dairy foods meat, fish, nuts, beans
water	essentials for life	all food and drinks
fiber	to help intestines work	fruit, vegetables

Some numbers

100 trillion

The number of bacteria living in your colon.

100 ml

(3.4 fl oz) The volume of water a person loses in their faeces each day.

20

The number of teeth in a set of milk (baby) teeth, which are replaced from age six onwards.

32

The number of teeth in a full set of adult teeth.

30 tonnes

The weight of food eaten in an average lifetime.

11 .5 liters

(14 pints) How much food, liquid, and digestive fluid flows through your digestive system every day.