As the weather warms up and our schedules show no signs of slowing down, smoothies are back on the menu as our go-to morning meal. Packed with produce, our beloved blended beverages taste just as good as ice cream... but are healthy enough to justify slurping one down at 8 a.m.

Or so we thought.

Here’s the thing: Some store-bought options (and even homemade blends) can easily pack more than 500 calories and 120 grams of sugar into your morning meal—that’s four times as much as a can of Coke(!)—if you're not watching your ingredients.

That’s why we dug into some of the most common smoothie add-ins to break down what’s packing in the good stuff... and which ones are pretty much pure sugar. So before you break out the blender, check out the best smoothie ingredients to keep adding and those to avoid if you don't want to drink the sugar equivalent of a... well, Slurpee.

The Best Smoothie Add-Ins

Plain Greek Yogurt

Adding a healthy dollop of Greek yogurt (packed with an average of 15-20 grams of protein per six-ounce serving) to your blender is a great way to keep you fuller for longer. It also adds a nice creaminess that will remind you of a diner milkshake. Just be sure to opt for the plain variety—flavored Greek yogurt is often just sugar wearing a dairy disguise.

Ground Flaxseed

It’s OK to get a little seedy with your smoothie. Sprinkling some flaxseeds will amp up the fiber, omega-3 fats, and protein content of your drink without changing its flavor. We love it because it doesn't really have a flavor, and after a few whirls in the blender, you'll hardly know it's in there.

Natural Nut Butter

Whether you’re a long-time peanut butter loyalist or all about the almond, there are natural varieties of most nut butters that will add richness and body to your beverage—without all the sugar. Make sure you read the label and look for ingredient lists that only say "peanuts" or "almonds" and maybe a little sea salt, but you don't need the added sugar that some brands sneak in there. Go ahead and add a spoonful of almond butter or your nut butter of choice for added protein, fiber, and good monounsaturated fats.

Unsweetened Milk or Nondairy Alternatives

Whether or not you’re dairy-free, making sure your base is unsweetened is key to making a better (and better-for-you) smoothie. While dairy milk has the added benefit of protein (about eight grams per cup), some plant-based milks are lower in calories (some are as low as 30 calories per cup). So make your pick based on what other protein-rich add-ins you’ve got going in or on your dietary preferences.

Greens

We all know how hard it is to eat all the veggies we're supposed to eat, so get those greens in early in the day by adding some to your smoothie. Toss in a handful of leafy greens like kale or spinach for an extra dose of nutrients, fiber, and that green color that screams "healthy." While kale has a more prominent taste than spinach, don't be scared of it; your other ingredients will mask any bitterness.

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Protein Powder

Adding a scoop of protein powder is a great way to balance out the sugar content of any fruit or sweet smoothie add-in. Steer clear of protein powders with paragraph-long ingredient lists (less is more!) that you can't understand, and obviously, shoot for no added sugar. You can also add a couple tablespoons of hemp seeds instead of protein powder so you know exactly what's going into your a.m. concoction. Plus, some protein powder flavors are so overpowering that they might make you wince every time you sip. Breakfast is too precious for that.

High-Fiber Fruit

Even when you’re trying to cut back on the sweet stuff, a smoothie still has to taste good or you'll be dumping it down the drain and making a run for the bagel shop. Add natural sweetness with high-fiber, lower-sugar fruits like raspberries, strawberries, and blueberries. Most of us are not getting our 25-38 grams of fiber each day from food alone, so adding more fibrous foods to your smoothie is an easy way to get your fix and stabilize your blood sugar levels.

Spices

Flavor doesn’t have to come from a spoonful of honey or syrup. Try adding a hint of warmth with your favorite baking spices and seasonings. A dash of cinnamon, nutmeg, allspice, cardamom, or vanilla adds tons of flavor while keeping sugar out of the picture.

Avocado

If you're craving a thick consistency that you typically achieve by adding bananas, but your bananas aren't ripe enough or you just want to cut back on fruit sugars, add a quarter of an avocado instead. The avo adds creaminess but zero sugar and will leave you feeling satisfied.

The Worst Smoothie Add-Ins

Fruit Juice

While I have no qualms about adding a splash of 100-percent fruit juice to a smoothie that’s otherwise packed with protein and healthy fats, if you’re trying to cut back on sugar, juice may be a good place to start. A cup of juice has about 23 grams of sugar, and while it is the healthy, natural variety, it still can spike your insulin if it’s not well-balanced with protein, fiber, or fat. Stick to just a splash and focus mainly on adding whole fruit.

Sweetened Fruit or Vanilla Yogurt

The yogurt aisle can be overwhelming, but for every protein-packed carton of plain Greek yogurt on the shelves, there are at least three options swimming in the sweet stuff. Some fruit-on-the-bottom brands of yogurt pack a whopping 24 grams of sugar and only six grams of protein per six-ounce container. Sorry, yogurt lovers, but that is hardly enough staying power to keep you satisfied until your next meal!

High-Sugar Fruit

We’re not telling you to avoid the goodness of nature’s candy, but a blender full of bananas isn’t a smoothie—it’s super-sweet baby food. It’s also not necessarily nutritionally balanced if you're hoping to get in a breakfast that will hold you over until lunchtime. If you want to cut back on sugar, limit some of the higher-sugar fruits like grapes, mangos, bananas, pineapples, and kiwis. If you simply can’t resist, mix them with protein and fat for a more balanced meal.

Sweetened Milk or Nondairy Alternatives

Most sweetened (or “original,” as they’re often called on the carton) milk alternatives can pack 10-12 grams of sugar per cup and negligible amounts of protein. If you decide to go with traditional dairy milk, beware the chocolate variety, which has 24 grams of sugar per cup—that’s more than a serving of Count Chocula! And at that point, wouldn't you rather just eat the cereal?

Sugar

OK, so this one may seem obvious. But a lot of smoothie shops still haven’t quite figured it out. We aren't talking about adding a scoop of the white stuff into the blender (if they do that, then definitely stop going there), but so many healthy cafes and juice bars feel the need to add honey, agave, coconut sugar, maple syrup, etc., which can all impact insulin levels. They may be more natural, but they are still considered added sweeteners that we promise you don't need. Trust us: If there's fruit in your smoothie, it's sweet enough. One other option is to add a Medjool date... it's sweet but has some fiber to help balance it out.

So, as it turns out, smoothies don’t have to be stealthy milkshakes masquerading as breakfast. With a few low-sugar swaps, you can easily throw together a smoothie as healthy as it is delicious.

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