Alcohol misuse: tackling the UK epidemic - London

4
Nutrition, exercise and obesity
Nutrition, exercise and obesity in adolescents
Adolescents in the UK are not eating optimal diets, often exercise too little and are increasingly likely to
be overweight or obese. This section discusses the current nutritional status of adolescents, their activity
patterns and the prevalence of obesity amongst this group. It outlines the policy approaches that have
been adopted to improve the situation in these areas and reviews the effectiveness of various interventions.
The nutritional status of adolescents
The diet of adolescents is important. Nutritional status can have an immediate impact on the health of
adolescents, contributing to obesity, susceptibility to illness and general health. Also, there is increasing
evidence that adult susceptibility to disease is associated with nutrition in childhood and adolescence. 10
The National Diet and Nutrition Survey (2000) examined the diets of British school children aged four to
18 years. It found that adolescents ate more than the recommended level of sugar, salt and saturated fat.
The most frequently consumed foods were white bread, savoury snacks, biscuits, potatoes and chocolate
confectionery. Although in general, average vitamin intakes exceeded recommendations, there was
evidence of low intake of some minerals in adolescents, especially in girls. 11
On average, adolescents fail to
eat the recommended amount of fruit and vegetables. The Health Survey for England 2001 found that less
than 20 per cent of boys and less than 15 per cent of girls aged 13 to 15 managed to eat five or more
portions of fruit and vegetables per day. 12
In 2000 less than half of 15 to 16 year olds in Wales reported eating
fresh fruit on a daily basis. 13
Much attention has recently focused on adolescents’ high consumption of fast food and confectionery.
Fast food typically incorporates all of the potentially harmful dietary factors including saturated and trans
fat (fat from partially hydrogenated vegetable oils), a high glycaemic index, high energy density and,
increasingly, large portion size. These foods also tend to be low in fibre, micronutrients and antioxidants;
dietary components that affect risk of cardiovascular disease and diabetes. 14
High salt consumption (over 6 grams per day, or over 5 grams per day for children aged seven to 14) may
also pose a health risk to adolescents. Eating too much salt, especially during childhood, has been
associated with the development of hypertension 15
and may even contribute to hypertension in the
young. 16
Adolescents’ diets are typically high in salt. Some pre-prepared meals, including many of those
marketed as healthy, have been found to contain more than the recommended daily intake of dietary salt
for an adult.
Adolescent consumption of soft drinks is also a cause of concern. The physiological effects of energy intake
on satiation appear to be different for energy in fluids as opposed to solid food. 17
This means that
consumption of energy at meal times may not be adjusted to take into account the energy consumed in
the form of soft drinks, thus contributing to obesity. 18
The Food Standards Agency and the Department for Education and Skills have recently undertaken
qualitative research into 14 to 16 year olds’ dietary knowledge and choices. Preliminary analysis suggests
that adolescents have a broad sense of the key constituents of a healthy diet but do not critically assess their
own diet in the context of recommendations. Respondents did not tend to check nutritional labelling and
generally did not weigh up the nutritional content of the foods that they chose for themselves. 19
British Medical Association Adolescent health