Professor Timothy Barrett has told ITV Daybreak that "many young obese children have very low self-estime and poor body image so they need sociological support."
David Hennessey, headteacher at St Peter and St Paul School in south London, says too many families are becoming reliant on fast food and see it as one of the main meals of the day.
National Obesity Forum member Tam Fry, who chairs the Child Growth Foundation charity, has warned about the "tragic" dangers of obesity in teenagers during pregnancy.
He said: "Girls are not only getting fat, but getting pregnant.
"The result is not only distressing for the girls but threatening for their children."
Talking about the increase of child admissions related to pregnancy, Mr Tam added: "I'm not surprised by this leap.
"A lot of these young people are completely unaware that piling on the pounds will not only make them fat but give rise to these other conditions."
The number of children being admitted to hospital for obesity related problems has quadrupled in less than a decade, a study has found.
Researchers from Imperial College London say the rise reflects increasing awareness among clinicians, who have become better at recognising obesity:
The burden of obesity is usually thought to have its serious consequences in adulthood, but we now see it manifesting earlier, in childhood.
It's clear that rising obesity levels are causing more medical problems in children, but the rise we observed probably also reflects increasing awareness among clinicians, who have become better at recognising obesity.
A study of the number of children and teenagers admitted to hospital for conditions linked to obesity between 2000 and 2009 found:
- A total of 20,885 young people were treated in hospital for obesity-related conditions.
- Teenage girls accounted for the biggest rise of admissions.
- In 2009, obesity is believed to have contributed to complications in 198 pregnant girls. Pregnancy complications included gestational diabetes, high blood pressure, the dangerous condition pre-eclampsia, and neural tube defects.
- The number of bariatric surgery procedures conducted to help children and young people lose weight also saw a sharp rise, from one per year in 2000 to 31 in 2009. Three-quarters of the patients were teenage girls.
Doctors in England and Wales have seen a four-fold increase in the number of children and teenagers admitted to hospital for conditions linked to obesity.
The rise in admissions from 872 to 3,806 occurred in the space of a decade between 2000 and 2009, according to research published in the online journal Public Library of Science ONE.
Researchers from Imperial College London analysed NHS statistics for children and teenagers aged five to 19 who had a written record of obesity.
Over the whole 10-year period, a total of 20,885 young people were treated in hospital for obesity-related conditions.
Nearly three-quarters of cases involved problems complicated by being overweight, such as asthma, breathing difficulties during sleep, and pregnancy complications.
Millions of lives could be saved every year if people ate more potassium-rich foods such as bananas and cut down on their salt intake, health experts have said.
People who have a high potassium intake have a 24% reduced risk of stroke, according to a new study.
And increasing levels of potassium - which can be found in many foods including fruit, vegetables, nuts, seeds, milk, fish, beef, chicken, turkey and bread - can help to reduce high blood pressure, the results indicate.
Researchers also said that increased levels of the chemical do not have an adverse effect on kidney function in adults.
Previous studies have suggested that older people are at an increased risk of harm from potassium because as people get older, their kidneys may become less able to remove potassium from their blood.
The Department of Health advises that older people should not have potassium supplements unless advised to take them by a doctor.
It says that adults need 3,500mg of potassium a day - which people should be able to get from eating a balanced diet.
The research, published on bmj.com, analysed data on potassium intake and health concerning 128,000 participants, who took part in 33 trials.
Health Minister Dan Poulter has told Daybreak that Family Nurse Partnerships will be good for the economy.
He said: "Mums and dads who benefit from the programme are more likely to go back into education, training and work."
Thousands of disadvantaged young mothers are to get more support bringing up their babies, Health Minister Dan Poulter has announced.
Daybreak's Cordelia Kretzschmar speaks to Antonia Trevena Jones, 17, and family nurse practitioner Amy Weston:
Parents have different needs and it is easy for problems and worries to be missed.
Having a specially-trained family nurse will give vulnerable families the support they need during the first 1,000 days, giving children the best possible start in life.