Good Question
New research intensifies the debate
Americans are inveterate snackers.
More than 90% of the U.S. population eats at least one snack a day, and most of us eat several. Some experts have called snacking “a hallmark of the American dietary pattern.”
Our enthusiasm for snacking isn’t new. Between the early 1970s and the late 2000s, the average number of snacks we consumed hardly budged; we ate two or three snacks a day back then, and that’s about how many we eat now.
While we may not be snacking more frequently than we used to, there’s some evidence that our snacks have gotten bigger.
Measured in calories, the average American man’s daily snack intake has ballooned by 26% since the early ’70s, while the average woman’s has increased by 48%. That’s according to a 2015 study in the Journal of the Academy of Nutrition and Dietetics, which concluded that snacks now make up roughly a quarter of the average American’s daily energy intake, and so effectively constitute a fourth meal.
These sorts of findings have prompted some doctors and dietitians to highlight snacking as a likely contributor to the country’s escalating rates of obesity and severe obesity. This opinion contradicts the once-dominant expert view that snacking helps curb hunger and reduces mealtime portion sizes, and so is helpful.
The more often we eat, the anti-snack faction argues, the more opportunities we have to overeat. If we could just quit snacking, everything would get better.
While there’s some evidence to support this position, the case against snacking is shaky.
A 2021 editorial in the Journal of Health Design — provocatively titled “Is snacking the new smoking?” — argued that calorie-dense snack foods have replaced tobacco products as a means of unhealthy self-reward and stress reduction, and that the pandemic has likely exacerbated our reliance on food as a form of emotional comfort.
This snack-as-safety-blanket idea has some solid research behind it.
“Emotional states are dangerous for people who are trying to eat sensibly,” says Kent Berridge, PhD, a distinguished university professor of psychology and neuroscience at the University of Michigan. “If you’re unhappily stressed, food can act like hedonic self-medication.”
A lot of Berridge’s published research explores the neural correlates of liking and wanting, which are closely linked yet distinct reward processes in the brain. “We used to think liking and wanting were the same, but they’re not,” he explains. “They have different systems and different neurotransmitters, and so it’s possible to want something very strongly even in the absence of liking.”
Berridge says that today’s convenience foods are engineered to tap into the brain’s reward system in ways that supercharge wanting. “Modern snack foods are sweeter, fattier, saltier, and more rewarding,” he says. Combine this intense palatability with the additional pressures of stress and entrenched habit, and the urge to over-snack can quickly blossom.
“If the food is healthy, I see no evidence — biochemical, animal, or human — that it’s a problem to eat frequently.”
While these factors may lead some to over-snack, some of the most recent and robust research on snacking has mostly failed to produce the kind of smoking-gun findings that some had anticipated.
A 2020 research review in PLOS One examined nationwide snacking data collected from thousands of U.S. adults.
When snacking was defined as any food consumption outside of mealtimes, the data revealed an association between snack size and body weight among women, but not men. A snack’s calorie count tended to be “significantly higher among women with obesity compared to women with normal weight,” the study’s authors wrote. But these associations faded when they examined other snacking-related metrics and definitions. On the whole, snacking didn’t seem to have much to do with a person’s weight.
“The purpose of this study was to examine the association between snacking frequency and weight status,” they explained. But, contrary to their expectations, “there was generally no difference in adiposity risk between the different snack definitions utilized in this analysis.”
Like so much of the snacking research — and nutrition research in general — the study fixated on body weight as a proxy for overall health. And so its findings don’t necessarily exonerate snacking.
But some experts who study nutrition and eating frequency say that snacking — like nearly all facets of human behavior — can’t be crammed into tidy good-bad categorizations.
“Everyone wants a simple yes or no, but snacking’s not like that,” says Valter Longo, PhD, a professor of gerontology and biological sciences at the University of Southern California.
Longo is one of the world’s foremost experts on the health benefits of fasting.
He says it’s clear that the human body benefits in many ways when it gets extended breaks from food. Those benefits may include improved immune-system health, as well as a reduction in risk factors for certain cancers, heart disease, and other illnesses. (An “extended break” could range from 12 hours to five days, though he says longer fasts are only safe with nutritional supplementation and expert supervision.)
You might think that a guy who champions intermittent fasting and time-restricted eating would be firmly anti-snack, but Longo’s not. He says that if people aren’t careful, snacking can lead to “more calories, bad foods, and longer periods of daily food consumption.”
“But if the food is healthy, I see no evidence — biochemical, animal, or human — that it’s a problem to eat frequently,” he says. “Especially if snacks are a substitute for a larger meal, I think they’re a good idea.”
He says that, when he’s trying to lose weight himself, he eats two meals a day — breakfast and dinner — and supplements those meals with two snacks, usually one around lunchtime and another in the early evening. Once he gets back to his desired weight, he goes to three meals a day, plus a snack. “People hear that snacking is healthy or unhealthy,” he says. “But it all depends on the person and what they’re eating.”
His views align with weight-loss resources from the Mayo Clinic, as well as the latest Dietary Guidelines for Americans, which tout snacks as a helpful way to fit more healthy fruits and vegetables into your diet.
It would be convenient — or at least straightforward — if the research came down conclusively on one side or the other of the snacking debate. But for now, it doesn’t seem like cutting out snacks is a clear route to improved health or weight loss.
Is Snacking Healthy? - Elemental - Elemental
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