To snack, or not to snack. That is the question.
Over 90 percent of Americans snack on a daily basis, according to the U.S. Department of Agriculture. And yet, the messaging around snacking and being healthy is still confusing.
Some proponents of snacking say that you should eat between meals to maintain stable blood sugar levels and prevent you from overeating later. However, others believe that it is important to give our stomachs time to empty out between meals and that snacking encourages us to reach for unhealthy food choices.
So, what does the science say?
"Surprisingly little has been published on snacking, despite the fact that it accounts for 20-25 percent of energy intake," Kate Bermingham, a researcher in Nutritional Sciences at King's College London, said in a statement.
In a recent study, Bermingham and her team analyzed the snacking behavior of 1,001 participants as part of the ZOE PREDICT project, a series of large in-depth studies coordinated by the personalized nutrition app, ZOE.
Using this data, the researchers examined the relationship between snacking quantity, quality and timing with blood fats and insulin, both of which are indicators of heart health and metabolism.
Of the 1,001 participants, 95 percent had at least one snack every day, with an average of 2.28 daily snacks, accounting for roughly 22 percent of daily calorie consumption. Four patterns of snacking emerged, which greatly influenced how people's bodies reacted to snacking.
The first was the morning snackers, who ate more than half of their daily snacks before 12 p.m. The second was the afternoon snackers, who mostly snacked between 12 and 6 p.m., and then there were the evening snackers who ate most of their snacks after 6 p.m. Seventeen percent of the participants had no distinct snacking peak and were classified as "grazers."
Of the evening snackers, those who tended to snack after 9 p.m. had more unfavorable blood glucose and fat markers compared to the daytime snackers. This could be simply because we tend to opt for less healthy snacks late at night, but it could also be because it shortens how long we are able to fast overnight.
Having a 12-hour gap between dinner and breakfast forces our bodies to break down stored fat reserves and may improve the health of our gut microbiomes. Eating late at night shortens this fasting window and makes it harder for our bodies to carry out metabolic housekeeping.
The results also showed that the quality of snacking was important. Participants who chose high-quality snacks—like fruits, veggies and nuts—tended to have healthier blood glucose and fat levels. Snacking quantity, however, did not seem to have a significant effect.
"Our study showed that the quality of snacking is more important than the quantity or frequency of snacking, thus choosing high-quality snacks over highly processed snacks is likely beneficial," Bermingham said. "Timing is also important, with late night snacking being unfavorable for health."
Bermingham will present her results at NUTRITION 2023, the annual flagship meeting of the American Society for Nutrition, on July 24.
