Study finds unhealthy snacking can increase risk of strokes, cardiovascular disease and obesity

The findings, published recently in the European Journal of Nutrition by researchers from the School of Life Course & Population Sciences and ZOE, detail the snacking habits of 854 people from the ZOE PREDICT study.

Researchers found that half of the participants did not match the healthiness of their meals to their snacks and vice versa.

This difference has a negative effect on health measures, such as blood sugar and fat levels, and addressing this could be a simple diet strategy to improve health.

"Considering 95% of us snack, and that nearly a quarter of our calories come from snacks, swapping unhealthy snacks such as cookies, crisps and cakes to healthy snacks like fruit and nuts is a really simple way to improve your health," said Sarah Berry, a Reader in nutritional sciences.

The analysis showed that the UK is a nation of snackers, with 24% of our daily energy intake from snacks such as cereal bars, pastries and fruit.

The average daily snack intake in people who snack – 95% of the cohort – was 2.28 snacks a day, with 47% of people eating two snacks a day and 29% of people eating more than two.

Contrary to popular belief, the analysis showed that snacking is not unhealthy - as long as the snacks were healthy.

People who ate high-quality snacks like nuts and fresh fruits frequently were more likely to have a healthy weight compared to those who don’t snack at all or those who snack on unhealthy foods.

Analysis also showed good quality snacks can also result in better metabolic health and decreased hunger.

However, a quarter (26%) of the participants reported eating healthy main meals and poor-quality snacks.

Poor-quality snacks, such as highly processed food and sugary treats, were associated with poorer health markers and left people feeling hungry.

Unhealthy snacks were linked with higher BMI, higher visceral fat mass and higher postprandial – the period after eating a meal – triglycerides concentrations, all of which are associated with metabolic disease such as stroke, cardiovascular disease and obesity.

The most popular snacks consumed were cookies, fruit, nuts and seeds, cheese and butter, cakes and pies and granola or cereal bars. The greatest contribution to calorie intake were cakes and pies (14%), breakfast cereals (13%), ice cream and frozen dairy desserts (12%), donuts and pastries (12%), candy (11%), cookies and brownies (11%), nuts and seeds (11%).

The timing of the snacking can also be crucial to your health, as analysis showed snacking after 9pm was associated with poorer blood markers compared to all other snacking times. Snackers at this time tended to eat energy-dense foods which were high in fat and sugar.

“This study contributes to the existing literature that food quality is the driving factor in positive health outcomes from food. Making sure we eat a balanced diet of fruit, vegetables, protein and legumes is the best way to improve your health.”