We are often told not to eat between meals, and there is a general perception that snacking is unhealthy. But, as usual when it comes to food, temptation prevails.
Snacking is very common, and increasingly so. In the early 1970s, for example, US adults consumed about 18 per cent of their total calories in snack form. By 2010, that had . Similar numbers have been recorded in the UK, and .
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This article is part of a series on nutrition that delves into some of the hottest trends of the moment. Read more here.
Given how common snacking is, it would be nice to know whether the received wisdom is true. But research on the health effects of snacking has produced a dog鈥檚 dinner of results. Some studies have found that, as expected, snacking has negative health consequences. But others have .
To get a clearer picture, earlier this year, at King鈥檚 College London, who is also chief scientist at the Zoe nutrition app, and her colleagues, they had gathered as part of an experiment carried out in 2018 and 2019, in which around 850 participants recorded everything they ate and when they ate it across two to four days. They were also tested on a range of measures of cardiovascular health, such as levels of blood fats and glucose.
Berry and her team found that 95 per cent of people in the study snacked, which they defined as consuming food or drink at least 30 minutes before or after main meals. The average number of snacks per day was 2.28, and around 24 per cent of calories were consumed in snack form. The researchers also devised a measure of the nutritional quality of snacks, called the snack diet index.
Snacking: good or bad?
Their overall finding was somewhat surprising: snacking, per se, isn鈥檛 associated with negative health outcomes. This contradicts one of the most common arguments against snacking. 鈥淭here are many people who say having multiple eating events throughout the day is bad for you,鈥� says Berry. 鈥淵ou need to give your body a rest.鈥�
Yet her team鈥檚 results suggest this isn鈥檛 the case. 鈥淭here was no difference in health outcomes depending on the number of eating events,鈥� she says. 鈥淚f you had three or if you had six, it didn鈥檛 matter.鈥�
But snacking isn鈥檛 a free lunch either. It depends on what you eat and when. Unsurprisingly, people who snaffled poor-quality snacks, such as biscuits, crisps and cakes, and/or ate after 9pm were worse off health-wise than those who didn鈥檛 snack at all or who snacked on nuts, seeds, fresh fruit and vegetables.
Research on the health effects of snacking has produced a dog's dinner of results
鈥淲hat seems to matter is the quality of the snack 鈥� obviously 鈥� and the timing,鈥� says Berry. The effect of late snacking may be due to the disruptions in circadian rhythms associated with eating at the wrong time.
But here鈥檚 the thing: people who snacked on healthy foods and didn鈥檛 snack late were better off than non-snackers. Snacking on fruit, vegetables, nuts and seeds earlier in the day is associated with a healthier weight and body mass index.
That may be because well-timed, healthy snacks reduce hunger and overall calorie intake. In 2022, a team at Winona State University in Minnesota with giving first-year college students 鈥� who often gain weight after starting university 鈥� a snack 90 minutes before their evening buffet meal. They either got 190 calories of walnuts, a 190-calorie gummy candy or no snack. The snackers ate fewer calories鈥� worth of food in the subsequent meal, and less overall, compared with the non-snack group, even with the snack factored in. The walnuts also proved more effective than the candy at reducing calorie intake. This suggests that eating a wholefood snack shortly before meals can reduce our overall energy intake.
Another thing to consider when reaching for a snack is why you are doing it. Research shows that most of us rather than hunger. 鈥淚f you don鈥檛 need the energy, that鈥檚 where it becomes a problem,鈥� says Berry.
at Purdue University in Indiana concurs with this view. He says our ability to gauge energy intake isn鈥檛 precise, 鈥渟o in the current environment where foods are abundantly available and social custom often dictates that we eat when we鈥檙e not hungry, that tends to be the problem鈥�.
This means that the planning 鈥� or not 鈥� of snacks is important. 鈥淲hen snacking is a planned eating event, then compensation [for calories at mealtimes] seems to be stronger,鈥� says Mattes. 鈥淲hen it鈥檚 an unplanned eating event, generally it鈥檚 less well compensated and so the energy from those types of snacks tends to add more to total daily energy intake.鈥�
The take-home message is that snacking isn鈥檛 automatically bad for your health 鈥� and can be positive. 鈥淚f you are a grazer, as long as you鈥檙e grazing on healthy food and not grazing late at night, current evidence would support that this can be part of a healthy, balanced dietary pattern,鈥� says Berry. 鈥淚t鈥檚 a simple dietary strategy that can improve your health.鈥�
鈥淚 think we have to accept that people want to eat more times per day than they used to,鈥� says Mattes. 鈥淭he real goal now is to understand how to incorporate it in a way that isn鈥檛 problematic.鈥�
