Discuss snacking among fitness and nutrition experts and you'll likely receive radically different views. Advocates argue snacks or "mini-meals" can curb appetite, stabilize blood sugar, and help you eat less during a subsequent meal.
Based on my research and experience helping people who struggle with weight-loss resistance, I'm against snacking for fat loss and fast metabolism.
Snacking has become a multibillion-dollar industry where savvy manufacturers push an ever-widening array of Frankenfoods loaded with high-fructose corn syrup and trans fat. Worse, gluten-free snacks, 100-calorie sugary packs, and nutrient-added cookies give people a halo effect about repeated snacking that contributes to overeating and weight gain.
Children and adolescents are particular targets for snack manufacturers. For instance, a study in the journal Preventive Medicine found the prevalence of snacking increased from 77 to 84 percent between 1977-1978 and 1994-1996 for children and adolescents.
Granted, that's not an astronomical jump: It shows snacking was common even 35 years ago. Sugary drinks proved a major culprit here, but more importantly, high-fat, salty snacks doubled during that time.
Researchers concluded the "large increase in total energy and energy density of snacks among young adults in the United States may be contributing to our obesity epidemic."
No kidding. But everyone, not just young adults, becomes more susceptible to fat gain when they snack. Here's why.
Snacking Raises Insulin Levels
Whenever you eat, your body secretes insulin, which delivers sugar from your bloodstream to your cells, then to your liver and muscle for storage.
These storage units, however, only take what they need. They aren't greedy. If you've still got sugar hanging out in your blood, your liver repackages that sugar as triglycerides. Insulin then stores those triglycerides as, you guessed it, fat.
Every time you snack, you raise insulin levels. Granted, those 100-calorie snack packs will raise insulin more than a handful of almonds, but snacking raises insulin, period.
"If you snack just as your insulin blood level is decreasing, it will promptly rise, even if you have a good snack such as fruit and nuts," says Eduardo Castro, M.D., a specialist in fat-loss resistance syndrome.
In other words, snacking keeps insulin levels elevated, which makes your body more readily store fat.
Snacks Rack Up Calories
A study in the European Journal of Clinical Nutrition found snacks have higher calories and lower nutrients than meals, and researchers cautioned against "a snack-dominating meal pattern."
These excess calories might be fine if they made you eat less at your subsequent meals, but that doesn't often happen.
Case in point: A small, eight-person study in The American Journal of Clinical Nutrition found that regardless of whether they ate a high-carb or high-protein snack, young men still ate the same amount at dinner. (Worth noting: The high-protein snack delayed hunger better, most likely because protein curbs your hunger hormone ghrelin.)
Researchers concluded, "A snack consumed in a satiety state has poor satiating efficiency irrespective of its composition, which is evidence that snacking plays a role in obesity."
You're Snacking for All the Wrong Reasons
You had a fight with your partner this morning, so a cheese Danish with your morning latte assuages that frustration. That afternoon your boss praises your third-quarter sales and you reward yourself with your coworker's homemade cookies. After a big dinner with your girlfriends, you're home watching Sex and the City reruns and realize there's a big jar of almond butter in the fridge. Even though you're not hungry, you instinctively head into the kitchen during a commercial.
Track your eating habits: You probably don't snack out of hunger. More often, you're bored, depressed, or celebrating some minor victory. Regardless, you've connected snacking with reward or gratification.
Kids learn these habits, too. A study in the Journal of Pediatric Gastroenterology and Nutrition found that how parents eat (and more specifically, snack) affects their children's behavior. So if you dive into a bag of Sausalito cookies while you're watching The View, kids are more likely to emulate this behavior.
Researchers in this study specifically looked at the snacking habits of 8- to 10-year-olds. They found savory snacks particularly triggered weight gain in those kids who, on average, ate an astounding four snacks a day.
Late-night Snackers Store More Calories
Most people inadvertently save snacking for evening hours. You know the scenario: You ate healthy all day, so you justify that half-eaten pint of Ben & Jerry's by rationalizing how it fits into your daily caloric allotment.
Fifteen minutes later, empty carton in hand, you resolve to do better tomorrow. I've got bad news to add to your guilt: Studies indicate that nighttime snacking stores more fat.
One small study in the American Journal of Physiology: Regulatory, Integrative, and Comparative Physiology found evidence suggesting that young females who snack at nighttime prevent fat breakdown and increase their obesity risks.
Another study in the journal Obesity showed mice fed a high-fat diet before sleep gained approximately 48 percent body weight, compared to mice that ate the same amount not at bedtime and only gained 20 percent.
This makes sense on a practical level: Those calories must go somewhere, and unless you're doing sprints while sleepwalking (not recommended, by the way), chances are they'll land on your midsection.
You've probably heard about intermittent fasting. You can get its benefits without hunger or deprivation by cutting your food intake off after dinner. That way, your body goes into fat-burning mode for about 12-14 hours until tomorrow morning's protein-rich breakfast.
For instance, a study in the journal Cell Metabolism found mice confined to an eight-hour feeding period became leaner and healthier than mice that casually grazed whenever they wanted to.
What if you did dinner right and still feel hungry before bed? Have a glass of water. A study at the University of Washington found everyone who drank just eight ounces of water before bed curbed their hunger completely.
What About Those Studies That Show Snackers Are Actually Leaner?
But wait, you say. Your receptionist munches on raw nuts throughout her day and she's lean.
Some studies do show snackers stay leaner than non-snackers. For instance, one in the Journal of the American Dietetic Association found high-fiber snacks could curb your appetite and help control your weight, whereas sugary snacks could "impede weight-loss progress."
Here's the deal. People who eat higher-fiber snacks tend to be more conscious about their eating habits overall. In other words, you're more likely to have a salad with chicken and avocado for dinner than nosedive into a deep-dish pizza.
Other pro-snacking studies reveal interesting loopholes. One in the Journal of the American Dietetic Association, for instance, found normal-weight people snack more and eat an average of five times a day compared to overweight people, who only eat about four times a day.
Researchers concluded that "three meals and two snacks per day [could] be important in weight loss maintenance."
Sounds good, right? Except read a little closer and you'll find while normal-weight people ate more often, they also ate on average fewer calories than overweight people.
Furthermore, the normal-weight people exercised about twice as much as overweight people. So while normal-weight people may eat more often, they also eat more smartly. Like your receptionist, they choose high-fiber, low-sugar whole, unprocessed foods like nuts and seeds.
When You Do Snack, Snack Smartly
Breaking the snack habit might prove challenging if you habitually reach for a sweet treat for every victory and mishap that comes your way.
Rather than deprive yourself, find a non-food reward. Take a spa half-day if you can afford it, or enjoy a hot bath or walk through the park to reduce stress and increase pleasure.
But I get it: occasionally lunch didn't satisfy you or you'll need something healthy to resist hot buttery movie popcorn. You'll have a snack. Do it right with one of these:
• Apple slices with almond butter
• Kale chips with hummus
• Raw nuts and seeds
• Plant-based (but not soy) protein smoothie with berries, kale, and unsweetened coconut or almond milk
• Celery with cashew butter
• Sliced natural turkey with avocado
Arble DM, et al. Circadian Timing of Food Intake Contributes to Weight Gain. Obesity (2009) 17 11, 2100-2102. doi:10.1038/oby.2009.264.
Bachman JL, et al. Eating Frequency Is Higher in Weight Loss Maintainers and Normal-Weight Individuals than in Overweight Individuals. Journal of the American Dietetic Association (November 2011) 111:11, 1730-1734.
Hatori M, et al. Time-restricted feeding without reducing caloric intake prevents metabolic diseases in mice fed a high-fat diet. Cell Metab. 2012 Jun 6;15(6):848-60. doi: 10.1016/j.cmet.2012.04.019. Epub 2012 May 17.
Hibi M, et al. Nighttime snacking reduces whole body fat oxidation and increases LDL cholesterol in healthy young women. Am J Physiol Regul Integr Comp Physiol. 2013 Jan 15;304(2):R94-R101. doi: 10.1152/ajpregu.00115.2012. Epub 2012 Nov 21.
Kong A, et al. Associations between snacking and weight loss and nutrient intake among postmenopausal overweight to obese women in a dietary weight-loss intervention. J Am Diet Assoc. 2011 Dec;111(12):1898-903. doi: 10.1016/j.jada.2011.09.012.
Maffeis C, et al. Could the savory taste of snacks be a further risk factor for overweight in children? J Pediatr Gastroenterol Nutr. 2008 Apr;46(4):429-37. doi: 10.1097/MPG.0b013e318163b850.
Marmonier C, et al. Snacks consumed in a nonhungry state have poor satiating efficiency: influence of snack composition on substrate utilization and hunger. Am J Clin Nutr. 2002 Sep;76(3):518-28.
Ovaskainen ML, et al. Snacks as an element of energy intake and food consumption. Eur J Clin Nutr. 2006 Apr;60(4):494-501.
Zizza C, et al. Significant increase in young adults' snacking between 1977-1978 and 1994-1996 represents a cause for concern! Prev Med. 2001 Apr;32(4):303-10.
University of Washington Study. 2002. Reported in Integrated and Alternative Medicine Clinical Highlights. 4:1(16).
© 2013 JJ Virgin & Associates, Inc. Celebrity Nutrition & Fitness Expert JJ Virgin helps clients lose weight fast by breaking free from food allergies. She is the bestselling author of Six Weeks to Sleeveless and Sexy, a Huffington Post blogger, creator of the 4X4 Burst Training Workout & co-star of TLC's Freaky Eaters. Her latest book, New York Times Bestseller The Virgin Diet: Drop 7 Foods, Lose 7 Pounds, Just 7 Days, is out now. Learn more at www.thevirgindiet.com.
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