Young people's diets should sustain growth, promote health - and be enjoyable. During this time a number of physiological changes occur which affect nutritional needs, including rapid growth and considerable gains in bone and muscle.

Nutritional considerations

Alarmingly, during the seven-day recording period, more than half the young people in the survey had not eaten any citrus fruits, leafy green vegetables, such as cabbage, greens or broccoli, eggs or raw tomatoes.

Iron deficiency
Iron deficiency is one of the most common nutritional deficiencies in the UK and adolescents are at special risk - up to 13 per cent of teenage boys and girls were found to have low iron stores. Rapid growth, coupled with a fast lifestyle and poor dietary choices, can result in iron-deficiency or anaemia. Teenage girls need to pay particular attention to iron as their iron stores are depleted each month following menstruation.

The main dietary source of iron is red meat, but there are lots of non-meat sources too, including fortified breakfast cereals, dried fruit, bread and green leafy vegetables. The body doesn't absorb iron quite as easily from non-meat sources, but you can enhance absorption by combining them with a food rich in vitamin C (found in citrus fruits, blackcurrants, green leafy vegetables). In contrast, tannins found in tea reduce the absorption of iron. Therefore, it's better to have a glass of orange juice with your breakfast cereal than a cup of tea.

Calcium deficiency
The report also highlighted that 25 per cent of teens had calcium intakes below recommended levels. This has serious implications for the future, with respect to bone health.

Osteoporosis is a bone disease that causes bones to become brittle and break very easily. Bones continue to grow and get stronger until the age of 30 - with the teenage years being the most important for development. Vitamin D, calcium and phosphorous are vital for this process. Calcium requirements for the teenage years range from 800 to 1000 mg per day.

Calcium-rich foods should be consumed on a daily basis. The richest source of calcium in most people's diet is milk and dairy products. Consuming a pint of milk a day or eating other dairy products will ensure a sufficient intake of calcium. Alternatively, try fortified soya milk.

Young people's diets should sustain growth, promote health - and be enjoyable. During this time a number of physiological changes occur which affect nutritional needs, including rapid growth and considerable gains in bone and muscle.

Foods to choose

In practice, this often isn't the case; average consumption of fat and sugars is high, while that of starchy carbohydrates and fibre is low. While undesirable, in the short term this won't do much harm. This only becomes a potential problem when this type of diet persists into adulthood.

Teenagers should be encouraged to choose a variety of foods from the other basic food groups:

• Plenty of starchy carbohydrates - bread, rice, pasta, breakfast cereals, chapattis, couscous and potatoes.
  
• Plenty of fruit and vegetables - at least five portions every day.
  
• Lots of dairy products, such as milk, yoghurt, fromage frais and pasteurised cheeses.
  
• Enough protein, such as meat, fish, eggs, beans and pulses.
  
• Not too many fatty and sugar-rich foods.

Other important dietary habits to follow during adolescence include:

• Drink at least eight glasses of fluid a day.
  
• Eat breakfast -it can provide essential nutrients and improve concentration in the mornings.
• Choose a fortified breakfast cereal with semi-skimmed milk and a glass of fruit juice.
  
• Take regular exercise, which is important for overall fitness and cardiovascular health, and also helps in bone development.
  
• Be sensible with alcohol - experimenting with alcohol is often part of growing up and asserting independence. If you do drink try not to binge and keep intakes within sensible limits.
  

Slimming

The most popular methods of losing weight are skipping meals; avoiding red meat, snacks and sugary foods; and even fasting. It has also been reported that teenage dieters have very low levels of calcium, vitamin C, beta-carotene, selenium, zinc, riboflavin and folate. This is a crucial age when a diet high in nutritional quality is important - and the so-called growth spurt increases the demands for these nutrients.

If you want to slim, make sure that firstly it's appropriate - are you really overweight or are you just dissatisfied with your natural body shape? Secondly, make sure you do it properly. Strict or faddy diets will be low in essential nutrients and frequent unsuccessful dieting can make your weight 'yo-yo'. Sensible eating and regular exercise is the only answer. Cut down on sugary and fatty foods, not foods from the other four groups. Don't let slimming get out of hand.

Despite this sensible advice, the teenage years are a time when eating disorders can manifest. If you think you may be suffering from an eating disorder, speak to your doctor or practice nurse, or get in touch with the Eating Disorders Association for confidential information and advice.

Vegetarianism
Vegetarians are often healthier than the rest of the population - they can be leaner, have a greater intake of key nutrients and generally be fit and well. Being a vegetarian while a teenager needn't be a problem, providing the diet is well balanced and provides suitable alternatives to meat, instead of simply cutting it out.

Meat provides protein, iron, essential B vitamins and zinc - all necessary for the growing teenager. Alternative sources include:

• Iron - fortified breakfast cereals, breads, dried fruits, beans, peas and lentils. Try to have two portions of iron-rich foods every day. To help with absorption, eat them with foods rich in vitamin C (eg, oranges, fruit juice, tomatoes and vegetables).
  
• B vitamins - if you're still consuming dairy products daily then intakes of these vitamins shouldn't be a problem. For vegans, vitamin B12 can be found in some yeast extracts, soya milks, breakfast cereals and TVP (texturised vegetable protein) products.
  
• Zinc - may be found in wholemeal breads, cereals, beans and pulses.

As a sensible precaution you may benefit from taking a vitamin and mineral preparation especially for vegetarians.

Acne
Contrary to popular belief, there's little scientific evidence that acne is caused or exacerbated by fatty and sugary foods. Hormonal factors are the most likely cause.

Key points

• Eat regular meals from the main food groups.
  
• Keep a sense of proportion about fatty sugary snacks and foods.
  
• Iron and calcium are the key nutrients in the teenage years, so make sure you're getting sufficient amounts by consuming milk and dairy products, and lean red meat or non-meat iron sources every day.
  
• If you want to slim - do it sensibly.
  
• Be active.
  
• If you do drink alcohol, be sensible and keep well within safe limits.