Last reviewed 19 November 2021

Obesity is one of the greatest long-term challenges that we currently face. Around two-thirds of the UK population are considered to be overweight and around 35 million are said to be obese. Former headteacher Michael Evans considers the growing problem of obesity and eating disorders in secondary schools.

The increase in obesity and its consequences

The last 30 or 40 years have seen a massive growth in eating disorders among all age groups, not just in the UK, but around the world. Obesity begins at an early age and often this can be linked to socio-economic background. For instance, five-year-olds from the poorest income groups are twice as likely to be obese, but by the age of 11, these same children will be three times more likely to be obese.

The National Child Measurement Programme uses body mass index as its guide and the latest 2021 data indicates a dramatic rise in annual figures for obesity. It shows that by the time English children are ready to start secondary school, just over one in four will be classed as obese.

Boys are more likely to be obese than girls and children living in the most deprived areas are at greater risk than those living in the least deprived areas.

Latest figures for 17-year-olds indicate that more than a third are overweight, but given the latest figures for younger children, if the current trend continues, rather than reducing, the number of obese adolescents is likely to significantly increase.

Adolescents and young adults make up approximately 20% of the UK population and they are effectively our future. In many ways, today’s young adults have a more responsible attitude to life than those of earlier generations. There has been a significant decline in underage drinking among young people, fewer now smoke and there has been a marked decrease in illicit drug use.

In spite of this, reports indicate that young people in the UK between the ages of 10 and 24 have poorer health and wellbeing outcomes than those of similar countries. Obesity, for instance, is more prevalent among older adolescents in this country than in almost any other high-income nation. Social and economic differences across all age groups have a profound effect on health. Those living in deprived areas are far more likely to be obese.

To give an idea of how the UK compares with the rest of the world, approximately 26% of the UK population is considered to be obese, compared to 40% in the USA and only 4% in Japan.

Being overweight can have serious effects on people of all ages, but to young people it can be particularly stressful during a time when they are trying to develop meaningful relationships. It can seriously limit their physical movement and there will often be feelings of shame and embarrassment about their appearance.

What is an eating disorder?

Generally speaking, an eating disorder will involve inadequate or excessive food intake and is usually accompanied by a range of emotional difficulties including low self-esteem, issues of control, a disordered perspective about weight and shape, and difficulty in managing mood and interpersonal relationships. It is responsible for more loss of life than any other mental health condition.

It is important to realise that eating disorders are not “normal” concerns about diet and body shape. Rather, they are serious mental illnesses with damaging physical consequences. They present complex problems that are unique to each individual and require professional treatment.

Binge Eating Disorder

There are three major eating disorders and over-weight people often suffer from Binge Eating Disorder. As it sounds, Binge Eating Disorder is where a person regularly binges on food, partly because they are always hungry and partly because when they see food, they have a compulsive desire to eat it. This usually results in further significant weight gain and can tip an already overweight person into obesity.

Obesity often inhibits any form of physical activity. Shame and disgust at appearance can lead to the avoidance of social situations. There is often a generally a feeling of being unable to control eating and weight. Social life is restricted as a result, and this can lead to depression, loneliness, helplessness, and self-anger.

Binge Eating Disorder is just one of several eating disorders that affect between 1.25 and 3.4 million people in the UK, around 75% of whom are female. Obesity can be present from an early age, but like other eating disorders, Binge Eating Disorder generally develops during adolescence, in this case usually between the ages of 14 and 25.

Anorexia Nervosa

Anorexia Nervosa is almost the opposite of binge eating. Here a person restricts their food intake to a point where their body weight falls to a level where their health becomes a cause for serious concern. Apart from extreme weight loss, major signs include tiredness, lethargy and fatigue, fainting and light-headedness, skin changes, hair loss, muscle wastage and difficulty in sleeping.

Sufferers will go to great lengths in their efforts to maintain a low body weight. They will avoid social situations involving food and they are likely to have compulsive routines to continually check their weight. Self-esteem will be at a low ebb, and they will have a continual belief that they are fat. This is a very serious psychiatric disorder that requires specialist assessment and intervention.

Anorexia Nervosa affects around 10% of people who have an eating disorder, and the average age of onset is around 16 or 17 years. There are many causes and often a number of different ones will have combined. Common causes are lack of self-esteem, social pressure, family breakdown, emotional issues, having a perfectionist personality, or feeling out of control with life.

Anorexia Nervosa has the highest mortality rate of any adolescent psychiatric disorder.

Bulimia Nervosa

Bulimia Nervosa is when efforts are made to control weight initially through not eating, but after resolve breaks down there will be bursts of compulsive eating of anything that is available, often in secret. Remorse immediately sets in, leading to the unpleasant process of getting rid of the food that has just been eaten.

There will be constant thoughts about food, coupled with anxiety in social situations if food is involved. Low self-esteem and body dissatisfaction are very common, as will be depression and feelings of embarrassment and shame.

Bulimia Nervosa accounts for 40% of people affected by an eating disorder and the average age of its onset is around 18 or 19 years.

What can schools do?

With all three conditions early intervention is essential and the most important action is to develop an eating disorder policy on the lines of the following.

  • It should clearly outline the school’s response to managing an eating disorder.

  • It must define the three main groups: Anorexia Nervosa, Bulimia Nervosa and Binge Eating Disorder, explaining the differences between them.

  • The objectives should be clear, why there is a need for the policy and how it is there to support students, parents, carers and staff.

  • It should include a clear chain of action, involving a nominated teacher and the school nurse. Parents should be advised to consult their GP and hopefully the school will receive feedback in return.

  • In situations of extreme concern, the school can contact Children and young people’s mental health services (CYPMHS).

  • There should be a named core team in the school, who should be identified.

  • There should be a policy of confidentiality.

  • There should also be a policy to cover how to manage a pupil who returns to school after treatment for an eating disorder, plus a further policy giving details of action to be taken if a pupil dies as a result of an eating disorder.


  • Obesity is one of the greatest health challenges that needs to be faced. When English children begin secondary school, more than 25% will have been identified as obese.

  • An eating disorder is a mental condition where an individual is unable to control food intake.

  • Binge Eating Disorder — where an individual effectively cannot stop eating.

  • Anorexia Nervosa — where an individual compulsively restricts food intake.

  • Bulimia Nervosa — where an individual tries to restrict food intake but loses resolve and following a burst of compulsive eating, gets rid of it in the easiest way possible.

  • Schools need to have eating-disorder policies that identify potential problems and clearly detail and appropriate action.