What’s good for your wallet isn’t always good for your waist. (Photo: Getty Images/Teri A. Virbickis)
Everyone loves a good deal, whether it’s 50 percent off a new pair of sneakers or a bulk bargain on staples like cereal and TP. But according to new research from the United Kingdom, supermarket sales might backfire when it comes to your waistline. That’s because people are more susceptible to price promotions on unhealthy foods compared to healthier items, the study found.
The researchers conducted an exhaustive analysis of food purchasing patterns among nearly 27,000 households in the UK. Subjects used barcode scanners and receipt images to record all of the foods and beverages they procured at supermarkets in 2010. From this data, researchers were able to learn a Big Brother level of information about the participants’ buying habits, including the number of items purchased, their nutritional content, and their price.
Not surprisingly, any price promotion increased sales. But deals had a much greater purchase-boosting effect among unhealthy categories of foods, such as crackers and frozen meats, compared to healthy food groups such as fresh fruits and vegetables.
Specifically, a 10 percent increase in the frequency of promotions boosted sales on healthy types of food by 20 percent, but increased the sale of unhealthy food categories by 35 percent, study author Theresa M. Marteau, PhD, a professor and researcher at the University of Cambridge, tells Yahoo Health.
The reason is simple: Nutritious fruits and veggies spoil in a matter of days, but packaged foods can last in your cupboard for months. So when you see a great deal on potato chips, you buy three bags and assume you’ll eat them eventually. But if strawberries go on sale, you’ll still only pick up one quart since that’s all you can eat before they go bad.
The problem, experts say, is that having huge portions of food around encourages overeating. “If you see special offers with tempting prices, be aware that if you stockpile food or drink, you’re likely to consume them quicker, and may end up consuming more,” Marteau cautions.
“Imagine you love chocolate chip cookies and buy three bags of them when they go on sale,” Kristin Kirkpatrick, MS, RD, LD, Cleveland Clinic Wellness Manager, tells Yahoo Health. “Now you have not a dozen cookies, but three dozen — and triple the chance to overeat them.”
Kirkpatrick cites a classic study from Cornell University where people ate 34 percent more popcorn when it was served in a large container versus a medium bucket, even though the popcorn was stale. Other research suggests that it’s the amount of food available — not necessarily the package size — that encourages overeating.
The findings do have an upside, says Patricia Bannan, MS, RDN, author of Eat Right When Time Is Tight. “The good news is that putting healthy foods on sale still makes people significantly more likely to purchase those foods,” she tells Yahoo Health. Bannan suggests the following tips to help healthy foods keep longer, once you’ve got them home:
- Blanch vegetables quickly, then spread them out on a baking sheet and place it in the freezer. Once the veggies are frozen, store them in a large freezer bag or vacuum-seal bag. This method works well for broccoli, cauliflower, asparagus, corn, carrots, and bell peppers, Bannan adds.
- Wash, pit, core, and slice the fruit as you would normally, then freeze them in a plastic freezer bag. Tossing apples or pears with a little apple juice before freezing will prevent the pieces from browning, she says.
The study also compared the frequency of sales between different grocery categories. Some people tend to think that junk food is promoted more often than nutritious foods, the researchers say. But the study found that this wasn’t true, at least in the UK. “It may be that promotions of less-healthy foods are given more prominent locations in stores to encourage sales, which are more likely to attract consumers’ attention,” Marteau says.
“Remember that a deal is only a deal if that includes your health in addition to your wallet,” Kirkpatrick concludes. “I tell my patients to apply the same rules about food choices regardless of sale or value.”