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The Unhealthiest Cereals on the Planet

Discover which brands will bowl you over, and which are just candy for breakfast, in our definitive list.
FACT CHECKED BY Jennifer Maldonado

Remember that old slogan "Mikey Likes It!" from the Life cereal commercial? Of course, he did. Life cereal is made with flour, oil, and sugar—the same ingredients as you'd find in a cookie!

You can do better—and should. A high-protein breakfast can lead to guaranteed long-term weight loss. Science proved it; of people who've lost 30 pounds or more, 78% kept the weight off by eating breakfast every day, according to a study done by The National Weight Control Registry. And while some brands have scrambled to maintain customers by cutting down on sugar and phasing out artificial colors, there are still a few Cookie Crooks out there.

That's why we scoured the cereal aisle to unbox the diet disasters wrecking your waistline. Watch out for these unhealthiest cereals you'll want to avoid, and for our complete lists of foods to avoid, don't miss our essential list of the unhealthiest foods on the planet.

How we graded them

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This list includes cereals with 11 or more grams of sugar per serving, and/or anything containing harmful ingredients—carcinogen-contaminated preservatives, artificial colors and flavor additives, and vegetable oils high in saturated fats.

When you're grocery shopping, we recommend looking for a cereal with at least 3 grams of fiber and no more than 10 grams of sugar per 1 cup serving. The fiber will help slow your body's digestion of the sugars, which can limit energy-draining spikes (along with subsequent crashes) in blood sugar that cause you to always feel hungry. Make sure you always skim the ingredient list, too: a whole grain should be listed as the first ingredient—not sugar—and ensure there are no artificial colors or flavors, preservatives, or partially hydrogenated oils. And if you're an oatmeal fan check out 16 Celebs Share How They Make Oatmeal.

Kellogg's Smart Start Original Antioxidants

kelloggs smart start breakfast cereal - unhealthiest worst cereals
Kellogg's
Per 1-1/4 cup: 240 calories, 1 g fat (0 g saturated fat), 260 mg sodium, 56 g carbs (3 g fiber, 18 g sugar), 5 g protein

Sorry, Kellogg's, but there's nothing smart about a high-sugar, low-fiber cereal. This Smart Start cereal hijacks the healthy-sounding claim "antioxidants"—compounds that mop up inflammatory, cancer-causing free radicals—making the cereal sound better for you than it is. In reality, their box contains an inexcusable 18 grams of added sugar per serving.

Kellogg's Cracklin' Oat Bran

kelloggs cracklin oat bran cereal - unhealthiest worst cereals

Per 3/4 cup: 230 calories, 8 g fat (3.5 g saturated fat), 65 mg sodium, 41 g carbs (7 g fiber, 16 g sugar), 4 g protein

Yes, it has "oats" and "bran," but Cracklin' Oat Bran also comes with nearly 20 grams of sugar if you eat a full cup, as well as a massive glut of palm and soybean oil that loads this box with inflammatory Omega-6s and saturated fats.

Mom's Best Crispy Cocoa Rice Cereal

Moms best crispy cocoa rice cereal - unhealthiest worst cereals
Post Consumer Brands
Per 1 cup: 170 calories, 1.5 g fat (0 g saturated fat), 240 mg sodium, 37 g carbs (<1 g fiber, 18 g sugar), 2 g protein

Although it's marketed as "Mom's Best," we're not sure if any mom would be happy to serve her child a bowl of cereal with 18 grams of sugar per cup. For one cup, you're looking at eating the sugar equivalent of 17 gummy bears for breakfast.

Malt-O-Meal's Chocolate Marshmallow Mateys

Malt o meal chocolate marshmallow mateys - unhealthiest worst cereals

Per 1-1/4 cup: 170 calories, 1.5 g fat (0 g saturated fat), 150 mg sodium, 37 g carbs (1 g fiber, 23 g sugar), 1 g protein

Generic brands, like this cereal from Malt-O-Meal, are cheaper, but that's because you're paying for sugar and chemicals—not healthy whole grains.

Cap'n Crunch Original

Capn crunch original - unhealthiest worst cereals

Per 1 cup: 150 calories, 2 g fat (0.5 g saturated fat), 290 mg sodium, 33 g carbs (<1 g fiber, 17 g sugar), 2 g protein

Did you know that Cornell University researchers found that cereal mascots, like Cap'n Crunch, who make eye contact with purchasers were the drivers of 28 percent more brand loyalty among cereal boxes? You may be loyal, but you're going to have to walk the plank if you think this cereal is good for you. It's high in sugar, low in fiber, and has no redeeming qualities.

Golden Crisp

Golden crisp cereal - unhealthiest worst cereals

Per 1 cup: 150 calories, 0.5 g fat (0 g saturated), 85 mg sodium, 34 g carbs (0 g fiber, 21 g sugars), 2 g protein

Did you know this box of cereal was initially advertised as a versatile cereal that could be eaten anytime from breakfast to dessert—and even in the place of candy? The mascot's name is even Sugar Bear, and the first ingredient listed in the cereal is sugar (and the third is corn syrup)! So it should come as no surprise that there are more than 21 grams of the sweet stuff in a cup. Count this as one of the foods that have more sugar than a donut.

Krave Chocolate

kelloggs krave chocolate cereal - unhealthiest worst cereals

Per 1-1/3 cup: 170 calories, 4.5 g fat (1 g saturated fat), 140 mg sodium, 32 g carbs (2 g fiber, 15 g sugar), 3 g protein

Kellogg's isn't even hiding the fact that they're trying to serve you a dessert craving for breakfast with these cereals called "Krave." They're mostly chocolate-flavored filling (yes, there's more sugar and soybean oil than there is whole grain in this cereal), and they also contain artificial colors and flavors.

Special K Fruit & Yogurt

Kelloggs special k fruit and yogurt cereal - unhealthiest worst cereals

Per 1 cup: 160 calories, 1 g fat (0.5 g saturated fat), 190 mg sodium, 36 g carbs (3 g fiber, 13 g sugar), 3 g protein

You've likely heard of the benefits of yogurt, but don't let that convince you to pick up this cereal. Kellogg's uses nonfat yogurt powder that's heat-treated (and, thus, contains no probiotics), and throws in a medley of inflammatory sugars, artificial flavors, and artificial colors that will knock your gut health off track.

Marshmallow Fruity Pebbles

Post marshmallow fruity pebbles cereal - unhealthiest worst cereals
Post
Per 1 cup: 160 calories, 1 g fat (0 g saturated fat), 240 mg sodium, 36 g carbs (0 g fiber, 18 g sugar), 2 g protein

It's not just the 18 grams of sugar per cup that did Marshmallow Fruity Pebbles in. It was also their addition of artificial colors—Yellow 5, Yellow 6, Red 40, and Blue 1. Red 40 and the two Yellows have both been banned from food products in the UK based on research that has connected the colorants with allergies, migraines, headaches, behavioral problems, and hyperactivity among children.

Mega Stuf Oreo O's

mega stuf oreo os

Per 1-1/3 cup: 160 calories, 2 g fat (0 g saturated fat), 210 mg sodium, 34 g carbs (1 g fiber, 17 g sugar), 1 g protein

Mega Stuf Oreos in a cereal form? Sounds like you'll be eating a bowl of sugar! In fact, one serving has nearly as much sugar as two Original Glazed Krispy Kreme donuts.

Cap'n Crunch OOPS! All Berries

Captain crunch oops all berries - unhealthiest worst cereals

Per 1-1/4 cup: 150 calories, 1.5 g fat (0.5 g saturated fat), 240 mg sodium, 33 g carbs (<1 g fiber, 17 g sugar), 2 g protein

OOPS! Cap'n Crunch opted to fill this box with sugary corn flour and artificial flavors and colors.

RELATED: 100+ healthy breakfast ideas that help you lose weight and stay slim.

Kellogg's Raisin Bran Crunch

Kelloggs raisin bran crunch - unhealthiest worst cereals
Kellogg's
Per 1 cup: 190 calories, 1 g fat (0 g saturated fat), 200 mg sodium, 46 g carbs (4 g fiber, 19 g sugar), 4 g protein

Here's a tip you should always follow when picking up a box of cereal: steer clear of the three C's. What are the three C's? They're crunch, crisps, and clusters. This trio is code for clumps of rice, oats, or corn held together by sugar and fat. That even goes for bran cereals like this one from Kellogg's. It's time to end Raisin Bran cereals' long-held reputation for being healthy. Dried fruits (like raisins) should be eaten in moderation because they don't fill you up as much as water-filled fresh fruit and are higher in sugar. Each of these boxes contains 13 grams of added sugars and 15 or more grams of sugar compared to fiber per serving, which is higher than what is expert-recommended.

Honey Maid S'mores

Post honey maid smores cereal - unhealthiest worst cereals

Per 1 cup: 160 calories, 3.5 g fat (0 g saturated fat), 270 mg sodium, 33 g carbs (1 g fiber, 17 g sugar), 1 g protein

Besides the fact that sugar is listed as the second ingredient in this cereal, this box of marshmallows and refined flour also earns a place on our list because it also includes artificial flavors, caramel color, and synthetic preservatives.

Honey Smacks

Kelloggs honey smacks cereal - unhealthiest worst cereals

Per 1 cup: 130 calories, 0.5 g fat (0 g saturated fat), 45 mg sodium, 32 g carbs (2 g fiber, 18 g sugars), 2 g protein

Wondering what the worst way to start your day is? It's with a bowl of this cereal, which contains 36 percent of your total recommended intake of added sugars for an entire day.

Quaker Real Medleys Cherry Almond Pecan Multigrain Cereal

quaker real medleys cherry almond pecan cereal - unhealthiest worst cereals

Per 3/4 cup: 240 calories, 7 g fat (1 g saturated fat), 35 mg sodium, 41 g carbs (3 g fiber, 15 g sugar), 5 g protein

The description of this cereal on Quaker's website? "Feed your sweet tooth and your, well, wholesome tooth." So at least Quaker realizes the amount of sugar (which totals more than five Chips Ahoy cookies worth) they put in this box.

Honey Oh's

post honey ohs - unhealthiest worst cereals

Per 1 cup: 170 calories, 3 g fat (0 g saturated fat), 240 mg sodium, 34 g carbs (<1 g fiber, 18 g sugar), 2 g protein

Oh no! Behind pulverized corn flour, this cereal is mostly sugar and molasses, and it has no redeeming nutritional qualities.

Cocoa Krispies

Kelloggs cocoa krispies - unhealthiest worst cereals

Per 1 cup: 160 calories, 1 g fat (1 g saturated), 150 mg sodium, 35 g carbs (0 g fiber, 15 g sugars), w g protein

Snap, crackle, pop? We commend Kellogg's for FINALLY removing artificial flavors and partially hydrogenated oils (trans fat) from this cereal, but there's still too much sugar (15 grams) if you pour yourself a one-cup serving.

Olivia Tarantino
Olivia Tarantino is the Managing Editor of Eat This, Not That!, specializing in nutrition, health, and food product coverage. Read more about Olivia
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