Despite the UK government introducing nutritional standards for school meals, pupils are still eating unhealthily at school, a study has shown.

A study by the consumer group Which? found that pizzas, chicken nuggets, chips and baked beans were often the basis for many school lunchtime meals, reported BBC Online.

Which? asked 246 children to keep food diaries. The study revealed many diets were lacking in essential nutrients such as iron, zinc, protein, calcium and vitamins A and C, but were high in saturated fat, sugar and salt.

The government introduced nutritional standards for school meals in 2001, but Which? said children’s diets do not appear to have improved since the consumer group last carried out a survey in 1992.

Which? found that school meals contributed less than 1.5 portions on average to the five portions of fruit and vegetables that the government recommends people eat each day.

Government inspections have shown a wide variety of foods, including healthy options, are available. However, children often opt for the less healthy alternatives.