Like the saying goes - we are what we eat. So it's important to eat right.
There is no right diet. But some foods, more than others, will keep us feeling healthy
Why eat right?
We eat for a million different reasons. Bad day? Chocolate on the way home. Birthday? Cake and candles. 7 o'clock? Mum says it's time to eat. Oh, and we also eat because we're hungry and we need to eat to survive! We eat, it tastes good, we get full, then we forget about it. But in fact, each mouthful stays with us for three more days as our body tries to use what we've chowed down to keep our bodies running. You are what you eat? You'd better believe it.
How much should I eat?
Calories needed per day for the average:*
- Girl - 2390
- Boy - 2820
- Girl - 2414
- Boy - 2964
- Girl - 2462
- Boy - 3083
- Girl 2462
- Boy - 3155
*This is just a guide, depends on how much activity you do also and how your body is developing during puberty
Food is fuel. The more we eat, the more we have spare, and that's when we start to store extra as fat. The more active we are, the more calories we burn up. Simple maths.
And what should I eat?
There is no right diet. But some foods, more than others, will keep us feeling healthy and looking great.
- Fresh fruit & veg - At least five daily. If you do nothing else, do this one. Different fruits and vegetables will give you different vitamins and minerals, so try to mix it up.
- Iron - Girls lose iron with each monthly bleed. Green veg or red meat will stop you running low.
- Calcium - Demand strong bones for life. Think dairy: milk, yogurt and cheese.
- Salt - Don't add extra.
- Saturated Fat - Good fats found in things like oily fish and nuts are great news. But the crisps, chocolates and biscuits aren't great if they're the staples of your diet.
Balance carbs (bread, potatoes, pasta, rice) and protein (meat, eggs, fish, beans) throughout the day. Keep your diet varied. A little of what you fancy does you good - no one's asking you to give up the odd doughnut. But try to focus on eating non-processed, natural foods that aren't full of chemical nasties as much as possible - as these are more likely to keep your body (and your mind healthy) and well.
BBC Dish Up has loads of ideas on how you can eat better, save money and have fun in the kitchen. Whether you want to know why your food bill is so big, or you're after the perfect food to fuel exercise, head over to bbc.co.uk/dishup for tips, tricks, recipes and inspiration.
Here are a few to get you started!
BBC Advice factfiles are here to help young people with a broad range of issues. They're based on advice from medical professionals, government bodies, charities and other relevant groups. Follow the links for more advice from these organisations. The BBC is not responsible for the content of external websites.
This page was last updated on 9 Oct 2017.