When It Comes to Diet Quality, Snacking Habits Often Overshadow Healthy Meal Choices

A new study finds that one in four people reverse the benefits of nutritious meal choices with unhealthy snacking, highlighting the importance of addressing patients' snacking habits to improve their diet and health outcomes.

The study, published in the European Journal of Nutrition, was conducted by researchers from the School of Life Course and Population at King’s College London in England using data from the ZOE PREDICT, a large nutritional research study. Investigators sought to examine how snacking frequency, quality, and timing can impact cardiometabolic health.

Included in the study was data from 854 people from the ZOE PREDICT study, which collected data on the participants’ self-reported snacking habits, health measures such as blood sugar levels, fat levels and BMI, age, sex, education, physical activity level, and mail meal quality. 

Approximately 95 percent of the participants reported snacking. The analysis showed that 26 percent of the participants reported eating healthy main meals and poor-quality snacks. According to the data, 24 percent of the participants’ daily energy intake came from snacks such as cereal bars, pastries, and fruit.

While the study did not find that snacking itself was unhealthy, the results suggested that poor-quality snacks were associated with poorer health markers and left people hungrier. In contrast, high-quality snacks like nuts and fresh fruit were associated with lower body weights, better metabolic health, and decreased hunger.

"Considering 95 percent 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, PhD, Associate Professor in the Department of Nutritional Sciences at King’s College London, and Chief Scientist at ZOE.

The study also showed that snack timing can impact health outcomes. The analysis revealed that snacking after 9 p.m. was associated with poorer blood markers compared to other snacking times. In addition, the data suggested that nighttime snackers tended to gravitate more to calorically dense foods high in fat and sugar.

According to researchers, these results indicate that poor-quality snacking can eclipse the benefits of good mealtime choices, underscoring the importance of staying consistent with healthy eating throughout the day.

"This study contributes to the existing literature that food quality is the driving factor in positive health outcomes from food,” said Kate Bermingham, PhD, from King's College London and senior scientist at ZOE. “Making sure we eat a balanced diet of fruit, vegetables, protein, and legumes is the best way to improve your health."