Do you take the time to shop for the freshest produce you can find, yet breeze right past the wet-wipes dispenser as you walk into your favorite market? That’s just one of the common mistakes that could put your health at risk and lead to some very painful illnesses. We took a round-trip from your front door to the market and back with Seattle-based lawyer and national food-safety expert Bill Marler to show you the pitfalls to avoid all along the route…

Before you leave home: Making sure your food is safe and practicing safe buying habits make up a process that starts before you set foot in the market. Yes, do pack your reusable bags to do your part for the environment, but give them a deep clean periodically and immediately when you see meat juice or any leakage while unpacking your groceries. These bags can become a haven for E. coli, Salmonella or Campylobacter from placing them on the ground as you unpack your car or on your less-than-spotless kitchen floor, as well as from the foods you load into them. If you clean your bags regularly, bacteria from them won’t get passed on to your next food purchases. Store reusable supermarket bags inside your house between shopping trips, and in warm weather, put them in the coolest part of your car as you head out. One study found not only large numbers of bacteria on most reusable bags tested but also that bacteria can increase tenfold if you keep your bags in your trunk while running errands for two hours.

Which brings us to the next thing to consider before you set foot in your grocery—your agenda for the day. Since perishable foods (any food kept under refrigeration at the store) can start going bad quickly, take a cooler loaded with ice packs if it will be more than 30 minutes before you get home. Leaving your food in the back of your car or, worse, in the trunk, especially during warm weather, gives bacteria the time and temperature they need to grow, increasing your risk of getting sick—and it can happen that fast.

At the store: The very first thing to do once you set foot in your store is to wipe down the handle of the shopping cart with a sanitizer. You may have heard about a study from the University of Arizona that detected more bacteria on shopping carts than in a public restroom. If your supermarket doesn’t offer a sanitizer at the entrance, bring your own.

Now, on to your food. While it’s important to “shop the perimeter” of markets because that’s where stores tend to keep their fresh, whole foods, Marler points out that fresh meats and produce are also the items at highest risk for contamination.

So, what’s the work around? With produce, a simple step you can take is to place each type of produce in a separate plastic bag. This isn’t to say that every food in your grocery store is contaminated, but the more you contain each food that could be contaminated, the more you reduce the risk for cross-contamination or exposure to other foods, Marler explained.

Marler acknowledges that precut fruits and vegetables make cooking easier for busy people, but he warns that precut produce has a higher risk for contamination because of the number of people who have handled it. Listeria is an especially problematic bacterium because it can grow in cool temperatures. So if a food is contaminated with Listeria before it gets to the market, even refrigeration (common for precut produce in markets) won’t prevent its spread. And Listeria is deadly, killing 25% of people exposed to it and hospitalizing 100%. One workaround for precut fruits and vegetables is to always wash them before eating or cooking with them, even if the packaging states that they were prewashed. Although washing may not get rid of all Listeria, the goal here is to reduce it to a level that can be defeated by your body’s immune system.

As for meat: Place packages individually into doubled plastic bags. Even though most meat and poultry come in packages that seem sealed, they generally are not sealed that well, and you don’t know what’s on the outside. Use separate plastic bags to catch any leakage and prevent these juices from mixing with other foods…even other packages of meat or poultry.

There are two specific foods that Marler never buys because he thinks the health risks are way too great—raw sprouts and raw milk. Sprouts thrive in warm, humid temperatures, the same conditions in which bacteria such as E. coli and Salmonella thrive, so the risk is greater than with other raw vegetables. And none of the purported health benefits of raw milk are worth the risk of consuming it—he sticks with pasteurized milk.

Marler also avoids grocery store salad bars and premade salads from the deli counter because it’s impossible to know whether all the necessary safe-handling steps were followed. After 25 years of litigating food-safety cases, he says that he’s just not the kind of person who wants to leave food safety to someone else.

As for canned and packaged products, be on the lookout for damage or tampering. Dented cans are always a risk because of the potential for small holes—a botulism spore could get in and grow in the can. Look out for your fellow shoppers by bringing a dented or bulged can to a store employee rather than just leaving it on the shelf.

Back home: The first thing you should do after unpacking your groceries is to wash your fruits and vegetables before storing them. Just a quick rinse under cool water, followed by patting dry, will help protect you, Marler says. Our bodies can handle some bacteria, so you don’t need to kill them all off. However, the sooner you consume produce, the better, he suggests. It’s not just that your food will taste better, but you reduce bacterial growth that can happen if produce sits around for a few days.

It’s no longer advised to rinse meat and poultry products before preparing them because you’ll end up spreading any contaminants in your sink. But do cook these foods within a few days or freeze them right away. Safely handling poultry products in particular is more important than most people think—because US food-safety law doesn’t include a “zero tolerance” policy for Salmonella and Campylobacter with poultry, you should assume that your raw poultry is contaminated. In fact, Marler takes the position that all meat should be considered possibly contaminated and safely handled.

And finally, when you’re in the home stretch, don’t ignore the more well-known safety practices that are important to preventing sickness—wash your hands well after handling meat and poultry, use a dedicated cutting board for these foods when raw and cook them to the recommended internal temperatures to help prevent illness.