We all assume millennials are obsessed with avocado and acai berries.

But research suggests that they may not be splashing out on healthy brunches as much as we think - because they are worried the food is too expensive, the Daily Telegraph reports.

Despite the stereotype that they are a health-conscious generation, 25-34 year-olds were more likely than any other age group to say that they struggle to eat healthily because the foods cost too much.

The survey, carried out by insurers Aviva, found that more than three quarters of young people were interested in eating more healthily but found themselves unable to afford the food.


Women were slightly more likely than men to say it was a problem, with almost 80 per cent stating that they struggled to afford healthy food, compared to 75 per cent of men.

Among those aged over 55 the proportion was just 54 per cent.

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Dr Doug Wright, the organisation's medical director, said the data "goes against the view that this is a generation who are juicing, detoxing and taking up all the latest healthy eating plans."

Young people also said they starved themselves during the day to "save up" calories for a big night out.

Half of men and almost 40 per cent of women aged 25 to 34 said they did this, as well as 48 per cent of people in their late teens and early twenties.

The majority of young women also said they were concerned they did not have a "healthy relationship" with food, with 65 per cent saying they worried about this.

Most millennials also said they had put themselves on a diet to lose weight in the past, including 61 per cent of men in this age group.

Dr Wright said: "Starving oneself can also lead to bingeing and overeating, which could mean ironically people take in more calories than through eating regular sensible meals.

"And if a big night out involves alcoholic drinks, this could mean people are swapping foods with a range of useful nutrients for 'empty calories' from alcohol with little nutritional value."

Figures released on Monday by Cancer Research UK suggested that millennials were set to be the most overweight generation since records began.