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Activities in Eating Explained

What does food give us?

Everyone knows that 'you need food to grow' but a common misconception is that growth happens anyway and that food just helps somehow.

The key idea here is that you are the food you eat and NOTHING ELSE.

A cow is reorganised grass and NOTHING ELSE.  A humming bird is reorganised nectar and NOTHING ELSE.

Food is the only thing that your body has to work with to build the incredibly complex machine that is you.  If you only eat simple foods like refined sugars then your body can't build complex things like brains, eyes and nerves.

Energy and food

Sugars, starches and fats are all used by the body for energy but provide it in different amounts.

Sugary foods provide instant energy when you need it (like a match) with any left over stored firstly as glycogen in your muscles and liver and eventually as fat.

Starchy foods still provide your body with sugars for energy but because they need to be broken down by digestion, they are released more slowly and provide a longer term energy supply (like a candle). These are important to keep your blood glucose level constant, which helps to stop you feeling hungry and maintain concentration.

Fatty foods are the most concentrated sources of energy and therefore your body doesn’t need too many of them to meet its energy needs.

Bones, muscle and blood

Teenagers are growing quickly and it’s important that they have the right raw materials in the right amounts to meet their body’s high demands.

It is important therefore to make sure their diet provides all the goodies needed without being too high in fat or sugar.

Grilled fish: good.  Fried fish in batter: not so good. 

Low fat yoghurt: good.  Cream cake: not so good.

Mince in chilli con carne with rice: good.  Cheeseburger: not so good.

Vitamins: unlocking the goodness

Vitamins perform many functions in the body of which other nutrients is just one.

The key idea is that there's no point in eating, say, carbohydrates if you don't also have the thiamin to be able to make use of them.

Your body only needs tiny quantities of most vitamins and is quite good at storing many of them. 

However, even if illness from vitamin deficiency is uncommon, the body will not work at its optimum if certain vitamins are lacking from the diet over the long term.

Play your cards right with calories

It's not just the energy content of food that's important but also what form it comes in: simple sugars, carbohydrates or fats.

However the bottom line is that if you consume foods that can provide more energy then you use (about 2100 kcal a day for a typical 15 year-old girl and 2700 kcal for a boy) then you'll store that excess energy in fat.

Students might be quite surprised to find which foods have a high calorie content.

Food and our ancestors

Our preferences for food start from before we are born and are influenced by the foods our ancestors needed to eat to survive when food supplies were often limited or difficult to access.

It is quite useful to compare what foods we eat now with the diet of our ancestors- what do you think they would say?

Why do some foods taste so good?

The most important short-term requirement for a living thing is that it has access to enough energy.

The body can extract energy from most types of food including protein and alcohol but if you're starving you want energy immediately, which is why we like sugary food. 

A stomach full of fatty food contains more energy than a stomach full of any other kind.  Since you might be disturbed in the middle of a meal or might not be able to carry around anything you can't eat straight away, you want to get as many calories on board as quickly as possible, which is why we have a taste for fatty food.

Again, it's our ancestors playing tricks on us.

Supermarket secrets

What we choose to eat is influenced not only our ancestors but also our contemporaries.

Food outlets and supermarkets use a number of strategies to encourage us to buy and therefore eat more than we need e.g  Buy 1 get 1 free, 3 for 2 or supersizing offers.

This activity will make students more aware of how these clever marketing strategies may affect their food choices.

What stops you doing more exercise?

The issue is with activity rather than 'exercise'.  Young people are more sedentary than ever before.

Simple changes such as taking the stairs not the lift or getting off the bus one stop earlier can make a difference.

We should all be aiming for 1 hour of activity 5 days per week.

Who could influence what you eat?

Research suggests that the approval of peers is one of the most important criteria for deciding whether to change a particular .

This is particularly true when looking at food choices and preferences.

If two friends agree to eat more healthily then they will both be doing the other a .

Eating disorders: The warning signs

Women aged 15-25 are the main risk group for eating disorders.  All disorders involve an obsessive dissatisfaction with body size, shape and weight and can be brought on by low self-esteem, stress, family problems or sudden loss.

Anorexia nervosa involves dieting to the point of starvation in order to lose weight with sufferers appearing emaciated to others but feeling fat themselves.

This is a often a secretive disease with sufferers disguising their problems by adopting a strict vegetarian or healthy eating diet and hiding their weight loss under baggy clothes.

People with Bulimia Nervosa are harder to spot as they are often normal weight but binge eat in private and vomit or take laxatives to purge themselves of food.

Eating disorders are potentially life threatening.

If you think you might be suffering from an eating disorder then the most important first step is to talk to someone you can trust.

Play your cards right with shelf lives

One of the problems in preparing fresh food is that you have to shop for it more often, or at least plan your shopping fairly carefully.

Frozen vegetables are just as good for you as fresh ones so this activity should help students understand how they can have a balanced diet that isn't too inconvenient.

Traffic light labelling

The traffic light system helps you see at a glance the amount of problem nutrients, like sugar and salt a particular food contains.

The system is based on 100g of the food to allow you to compare foods directly but there is also information per serving as well so you now how much you have eaten.

Any food with a red light should be eaten in moderation with the majority of our diet made up from foods with green or amber lights.

The balance of good health

There are so many reasons why a good diet is important but what does one look like?

The Balance of Good Health illustrates what foods we should be eating and in what proportions on a daily basis.  This ensures we have enough of the things we need and not too much of the things we don’t.

BOGH targets per day are:
5 servings fruit and vegetables
3 servings milk and dairy foods
2 servings of meat, fish and alternatives
3+ servings bread, cereals and potatoes
Limited fatty and sugary foods

Note that butter counts as a fatty food rather than a dairy food and that nuts, pulses and peas belong in the protein group.

Fat, dieting and fitness

Around 50% of adults at any one time say they are trying to lose weight.

Even if students are not worried about their weight at the moment it's likely that they will at some point in the future.

The key message is that a certain amount of body fat is desirable and natural but that if you want to lose any excess there are right and wrong ways to go about it.

Losing fat is a long-term lifestyle decision requiring a balanced diet and regular exercise.

A diet as a one-off event is very unlikely to help you lose fat and keep it off.

Stages in changing how you eat

The important idea here is that there isn't always a black and white distinction between the different choices people make about their lifestyles.

This approach identifies five stages that a person may be at, which we could call precontemplation, contemplation, preparation, action and maintenance.

The advice and support you would offer should depend on the stage.

Even if this may seem overcomplicated we hope that all students will benefit from the increased self-awareness that this activity will give them.

Food myths

Food is something that affects everyone and everyone has their own ideas,  thoughts and beliefs about it, some of which may be right and some of which may be wrong.

This activity helps to clarify the fact from the fiction.

Healthy menus

The food people choose to eat is often very habitual because of preference, cost and convenience.

To ensure that any positive changes to their diet continue long-term, it is often easier to adapt foods already liked to make them healthier.