Every week Americans head to the grocery store knowing what should fill their carts — fruits, vegetables and unprocessed foods packed with whole grains.
Yet many end up walking out with bags full of sugary cookies, a couple of frozen meat lovers' pizzas and liters of soda.
This happens most in the Minneapolis-St. Paul-Bloomington metro area, where shoppers spend 11.47 percent of their yearly grocery bill on unhealthy items (the national average is 8.5 percent). In second-place Richmond, Va., that number drops slightly, to 11.45 percent, and in Indianapolis and Carmel, Ind., No. 3 on our list, unhealthy items eat up 11.33 percent of a typical grocery shopper's bill.
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Chicago-Naperville-Joliet and the Charlotte-Gastonia-Concord region in North and South Carolina round out the top five.
While we all indulge every now and then, new data show that shoppers in certain portions of the country are more prone to regularly buying unhealthy items at the grocery store than others, due in part to a mix of regional, community and familial influences.
Behind The Numbers
To determine the country's unhealthiest grocery shoppers, Forbes.com used data compiled by St. Petersburg, Fla.-based Catalina Marketing, a company that specializes in developing behavior-based marketing strategies.
Catalina tabulated what percentage of grocery shoppers' purchases consisted of unhealthy foods across the country's 50 largest Census-designated metropolitan statistical areas from June 2007 through June 2008. To do so, analysts calculated the total amount of money spent on more than 100,000 individual product codes deemed generally unhealthy at 17,000 grocery stores. Those figures were then corrected for total expenditures in grocery stores.
Grocery stores that provided data excluded some small independent stores, club and mass merchandisers, drug stores, natural foods stores, such as Whole Foods, and Wal-Mart, which does not share its numbers.
Unhealthy purchases included cake and brownie mix, cookies, a wide range of candy, frozen pizza, regular mayonnaise, chips, sodas, ice cream, bacon and sausage.
Most nutrition and health experts were not surprised that states in the Midwest and the South topped our list. People's eating and purchasing habits are largely formed by the tastes they grow up with: the familiar and comforting, or, in the South, where obesity rates soar, deep-fried food and in the Midwest, pop and pizza.
"Grocery shoppers, who are usually female, think, 'This is what I've been eating or this is what grandma cooked for me and this is what I'm going to make for my family,'" says Gloria Tsang, a registered dietitian and founder of the online nutrition community HealthCastle.com.
People are also more influenced by the dietary choices of friends and family than they realize, says Dr. Robert Kushner, weight-management expert and professor of medicine at Northwestern University's Feinberg School of Medicine. Research out of Harvard Medical School and the University of California San Diego published in the New England Journal of Medicine last year showed that obesity and thinness are socially contagious, with friends, siblings, spouses and neighbors affecting each others' eating habits and physical activity levels. In other words, if your friends tend to skip the gym and go out for ice cream, you're likely to as well.
There are socio-economic factors at work too. If you live in a community full of convenience stores and restaurants that sell food in wrappers, it's probably affecting your diet on the whole, including the choices you make in the grocery store, Kushner says.
In addition, if the people in your neighborhood or community are on the heavy side, you may not even realize that you could stand to lose a few pounds too. Being overweight is the norm.
People who tend to make unhealthy grocery store purchases usually don't need more nutrition education, experts say. They need help breaking their bad habits. Most people, for instance, know that they should order the side salad or fruit cup when they go to a McDonald's, but that doesn't matter if they don't have the mindset to resist the smell of French fries hanging in the air, says Joy Bauer, registered dietitian and author of Joy Bauer's Food Cures.
The first step, Bauer says, isn't an instant diet makeover, which will likely set you up for failure. Instead, start by making a grocery list that includes a few healthy items you and your family like. That will help you break out of the rut of just buying all of the snacks and processed foods that you're running low on in the pantry. Lists are also great if you're prone to unhealthy impulse buys or you're shopping with kids in tow and need to get in and out of the store quickly.
There are lots of little things you can do to make those favorite foods more figure friendly too. Holly Clegg, the Baton Rouge-based author of the new cook book, Holly Clegg Trim & Terrific Gulf Coast Favorites, tells people they can still eat cake and pizza, they just have to cut the butter, use reduced-fat cream cheese and egg whites and load on the vegetables toppings. Many popular southern dishes can be made in the oven, instead of the frying pan, with little loss in flavor too.
For people worried about losing taste along with calories, Clegg suggests shopping with an eye toward fruits and vegetables in season and at their peak in terms of juiciness and flavor. Replacing soda with flavored tea would also cut your intake of calories and sugar while keeping your taste buds happy.
You might also consider skipping the grocery store altogether. A study published in The International Journal of Behavioral Nutrition and Physical Activity last fall, showed that people trying to lose weight who ordered their groceries online were able to reduce the amount of food in their home--and of high-fat items in particular.
Don't discount the importance of attitude and persistence, either.
"Being healthy is 50 percent attitude," Bauer says. "If you make up your mind you're going to do it, you will find a way."