10 Worst Supermarket Rip-Offs

But make a few mistakes and you'll leave with an empty wallet—not to mention a lot of empty calories. In fact, even the lowest-priced supermarket in your neighborhood is brimming with complete rip-offs—"health" foods that aren't healthy, "gourmet" foods that aren't gourmet, specialty items that just aren't that special.

Here are just some of the foods you're overpaying for, plus some weight loss-friendly swaps:

Organic Onions and Avocados

The Environmental Working Group, an organization that studies pesticide contamination, ranks onions and avocados among the most-pesticide-free vegetables and fruits, respectively—even when grown conventionally. In fact, as a general rule, anything you have to peel before you eat it (such as a banana or garlic, for example) is relatively low in pesticides. If you want to eat organic, splurge on produce with permeable or edible skin, such as peaches, lettuce, and apples—one of these 30 Foods That Uncover Your Abs for Under $1!

Bottled Spices

What all those TV chefs say is true: You should try to refresh your spice cabinet as often as possible—at least once a year. Over time, spices' essential oils fade, and with them goes the flavor you're looking (and paying) for. So what's a savvy cook to do, pay $6 for a bottle of star anise you're only going to use twice a year? Absolutely not. Instead, shop at stores like Whole Foods and ethnic markets where you can buy all your spices from bulk containers that allow you to choose the amount. Fifteen grams of cardamom or cumin or coriander will cost you about a quarter of what a normal supermarket charges for a small bottle and will last you the better part of a year. Plus, high turnover ensures you're getting potent spices—not something that's been sitting on a shelf since Reagan left office.

Swordfish

A pound of swordfish can cost more than $20. Why? Supply and demand: Because it's scarce, it's viewed as a luxury. But you should consider its high cost a blessing: It probably has saved your family from slow, steady infusions of poison. Due to its abnormally high levels of mercury, the Environmental Defense Fund recommends that children and women who could potentially become pregnant cut swordfish from their diets entirely. A better seafood option: wild salmon. It's a meaty, flavorful fish like swordfish, but it's nearly contaminant free, and costs about half as much

Gluten-Free Baked Goods

Gluten-free foods generally cost two to three times more than their gluten-containing counterparts, and unless you're among the less than 1 percent of people with celiac disease, there's no point in coughing up the extra dough. Gluten-free pastries and breads don't necessarily have fewer calories or more nutrients than regular products. A 2006 study published in the American Journal of Gastroenterology followed a group of gluten-free dieters with celiac disease for 2 years and discovered that 81 percent of them actually gained weight.

5-Hour Energy

There's a lot of hype about this bottle, but the only ingredient that provides any significant energy is caffeine, of which there are 135 grams in each bottle. That's less than you'd find in a 14-ounce cup of coffee (a Dunkin' Donuts 14-ounce medium has about 164 grams of caffeine). Cost for a cup of coffee: A buck or two. Cost for 5-Hour Energy: $3 to $4.

Tenderloin Steak

This is consistently one of the most expensive cuts of beef, but all you're buying is a little bit of tenderness. In fact, tenderloin isn't a particularly flavorful steak. So why does it cost so much? Because there aren't many tenderloin steaks on a cow, and because demand from diners looking for beef that cuts like butter tends to be high. Switch to skirt or flank steak instead. They're both lean cuts that pack far more rich, deep, beefy flavor. Marinate for at least 4 hours in a 50-50 solution of balsamic vinegar and soy and you'll have a steak you can cut with a spoon. Most importantly, it will cost you about half of what you would pay for that tenderloin. Remember this next time you're at the steakhouse, too. And speaking of meat and protein be sure to stock up on some of these 29 best Ever Proteins for Weight Loss.

Anything with a Cartoon on the Box

You know there's trouble when a food needs a mascot. A grinning cartoon character on the front of a box is a surefire sign of two things: 1) The box is filled mostly with cheap carbohydrates, and 2) most of the money you spend on it will end up in the pockets of marketers. See the Post Golden Crisp box here? The mascot on the front is known as Sugar Bear, which explains why more than half the calories come from sugar. This box is like a billboard for obesity. What should you be pouring into your bowl instead? Any of these 11 Best Brand Name Cereals for Weight Loss are safe bets.

Sugar-Free Packaged Foods

If you're craving something sweet, skip "sugar-free" options and eat what you're really craving in moderation. (If you're diabetic, consult with your doctor for healthy, safe ways to cut down on processed "sugar-free" foods in your diet.) Why? Not only are conventional products typically cheaper, when manufacturers take sugar out of products, they often add in bad-for-you fats like palm oil and cream to make up for the taste, explains nutrition expert Toby Amidor, M.S., R.D. "They also use sugar alcohols, which can have a laxative effect if eaten in excess."

Microwave Popcorn

A 30-ounce container of popping corn costs about $4 and makes anywhere from 10 to 12 bowls. However, the microwaveable varieties which come in a box, inside their own individual bags, are an entirely different beast. They are often the same price but yield about half the amount of popcorn. But that's not all. Many major brands like Jolly Time and Jiffy Pop not only contain heart-harming trans fats but also line their bags with perfluorooctanoic acid (PFOA), the same toxic stuff found in Teflon pots and pans—that's why it's one of these 20 Unhealthiest Foods on the Planet. Stay away from the stuff at all costs.