Are middle-aged people more unhealthy than ever?

About one in three middle-aged Britons has multiple health conditions - such as chronic back pain, mental ill health and high blood pressure, a study suggests.

But is this decline just an inevitable part of middle age every generation has to face - or is this current cohort of 40-somethings less healthy than previous ones?

According to researcher Dr Dawid Gondek, from University College London, who led the most recent study, overall trends show this generation is not doing so well when it comes to their health.

It is not that straightforward to compare previous generations - because data isn't always available or collected in the same way - but studies suggest levels of mental ill health, obesity and type 2 diabetes have increased, alongside other chronic conditions.

Dr Gondek suggests worsening diets, less exercise and an increase in air pollution play a role.

And when it comes to stress, research in this area is relatively new - but some scientists suggest jobs have become more stressful in recent years, which is likely to play out as worsening mental health in the years to come.

It is not all doom and gloom - for example, studies suggest education levels have increased and alcohol consumption has decreased in recent years.

And an increase in health literacy may also be important - more people take an interest in the conditions they have and are more likely to report them in surveys, for example.

But despite this, Dr Gondek says, for people currently in their late 40s, a complex mix of factors has led to overall worsening health.

Kevin Wright, 46, an information-technology (IT) project manager, from Leicestershire, says it is not too late to turn things around.

Having had back pain for most of his life, in his early 40s he noticed he was becoming breathless climbing the stairs.

"I was eating all the wrong food, drinking regularly and feeling grumpy after a heavy night," he says.

And he realised he needed to make some changes.

About five years ago, Kevin:

He cut out processed food and now drinks on special occasions only.

"The worst thing was giving up the alcohol - that was hard, a month or two of realising I couldn't have a drink when I came home from work," Kevin says.

And when it comes to diet, "the biggest challenge is sharing a home with my family who are eating different things, and feeling like the odd one out".

To keep motivated, Kevin uses apps to track his fitness and join in challenges with others.

"Having the camaraderie of the football team is good for my physical and my mental health too," he says.

In his 20s and 30s, Kevin travelled abroad with his job, ate out a lot and "was not healthy at all" - but he feels so much better now he has lost weight.

"I'm running faster in my 40s than I was in my 20s," he adds.

Childhood is the most critical time to intervene, Dr Gondek and his team say.

And responsibility for this rests on policymakers and parents alike.

Reducing inequalities in health and education and increasing access to healthy food are crucial, for example.

His study suggests body-mass index (BMI), which relates a person's weight to their height, at the age of 10 is strongly linked to middle-age health.

Other important factors include socioeconomic circumstances, with people whose fathers had "unskilled jobs" faring worse than those in professional roles.

Mental health at the age of 16 is also important - those who said they were more anxious or badly behaved at this age were more likely to have mental-health and physical conditions in middle age.

There are many theories about why health in childhood has such an impact on later life - with genetics and environment playing important roles.

Some scientists, for example, say obesity drives inflammation in the body, disrupting hormones and healthy growth.

Obesity can also increase the general wear and tear on the body - much of the science is still being worked out.

But the focus on future generations of adults should not distract from what those in their 40s right now - and what those in charge of policies - can do to improve health, Dr Gondek says.

Healthy eating, regular exercise and cutting down on cigarettes and alcohol can improve people's health in mid-life and set them up for a smoother ride into older age.