Two new scientific studies published in the British Medical Journal confirm what many parents have feared for some time; that munching on so-called ultra-processed foods is linked to poor health and shorter lives.

One study, conducted by researchers at Spain's University of Navarra, tracked 19,899 people over 10 years and found that, for every 10 deaths among people who ate mainly unprocessed food, there were 16 among those with a soft spot for ultra-processed food.

Another study, carried out by experts at the University of Paris, in France, followed 105,159 people over five years and found that those who ate mainly ultra-processed food had weaker hearts than their peers. It reports a 10 percent increase in consumption of ultra-processed food caused a 12 percent increase in cardiovascular disease, a 13 percent increase in coronary heart disease, and an 11 percent increase in cerebrovascular diseases, which affect blood supply and can trigger a stroke.

Maira Bes-Rastrollo, a professor at the University of Navarra, told BBC News such foods are widespread.

"It is said that if a product contains more than five ingredients, it is probably ultra-processed," Bes-Rastrollo said.

Mathilde Touvier, from the University of Paris, added: "The rapid and worldwide increasing consumption of ultra-processed foods, to the detriment of less-processed foods, may drive a substantial burden of cardiovascular diseases in the next decades."

Examples of ultra-processed foods include breakfast cereals, ice cream, chicken nuggets, and packaged snacks. Typically, they have been through extensive processing and have a long list of ingredients, including color enhancers, preservatives, and sweeteners. They tend to be high in sugar, fat, and salt and lacking in fiber and vitamins.

Touvier said the evidence against such foods has been piling up for a while.

"Increasing numbers of independent studies observe associations between ultra-processed foods and adverse health effects," Touvier said.

Last year, a study found a link between such foods and an increased risk of developing cancer.

But researchers caution that, despite poor diet appearing to create poor health, it is possible that other factors also play a part. For example, people who eat a lot of ultra-processed food are also likely to have other unhealthy behaviors, such as smoking.

As for why such a diet may cause poor health, an earlier United States study found that people who ate more ultra-processed foods than their neighbors tended to be fatter. It is thought that weight-gain and the detrimental impact of additives are likely among the reasons why ultra-processed foods may be bad for health.

The British Heart Foundation recommends people try to stick to a "Mediterranean-style diet" and prioritize vegetables, fruit, nuts, fish, seeds, lentils and beans.

Fact Box

Examples of ultra-processed foods

Breakfast cereals

Cake

Cereal bars

Chicken nuggets

Chocolate

Hamburgers

Ice cream

Instant soup

Meal-replacement shakes

Packaged snacks

Pies

Pizza

Poor quality bread

Ready meals

Sausages

Sugary fizzy drinks