Middle aged people in England face a health crisis
Desk jobs, fast food and the daily grind are taking their toll, says Public Health England. Eight in every 10 people aged 40 to 60 in England are overweight, drink too much or get too little exercise, the government body warns.
PHE wants people to turn over a new leaf in 2017, and make a pledge to get fit.
Health officials say the "sandwich generation" of people caring for children and ageing parents do not take enough time to look after themselves.
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We are living longer, but are in poorer health because we store up problems as we age.
The campaign's clinical adviser, Prof Muir Gray, said it was about trying to make people have a different attitude to an "environmental problem".
"Modern life is dramatically different to even 30 years ago," Prof Gray told Radio 4's Today programme, "people now drive to work and sit at work."
"By taking action in mid-life... you can reduce your risk not only of type 2 diabetes, which is a preventable condition, but you can also reduce your risk of dementia and disability and, being a burden to your family," he added.
Many people no longer recognise what a healthy body weight looks like, say the officials - and obesity, which greatly increases the risk of type 2 diabetes, is increasingly considered normal.
The PHE website and app has a quiz that gives users a health score based on their lifestyle habits by asking questions such as, "Which snacks do you eat in a normal day?" and "How much exercise do you get every day?".BBC