Smoothies aren’t always healthy—here’s how to ensure your next one is

There are few foods out there with more of an enduring healthy reputation than smoothies. Experts love to recommend them for breakfasts, colorful recipes are splashed all over wellness influencers’ feeds, and they’re a mainstay of many wellness-minded restaurant menus.

It makes sense as to why we love them, too. They’re delicious, beautiful, portable, and relatively easy to throw together in the blender. They seem to be a perfect snack or breakfast, depending on what you put in them.

But considering that we are unfortunately in a climate of peak nutrition information overload—even second-guessing the health merits of certain vegetables, no less—it’s worth revisiting the health merits of the perennial favorite that is the smoothie. Are smoothies healthy, or have we just been fooling ourselves for years? Here’s what you should know.

So, real talk: Are smoothies healthy?

Unfortunately, not always. “Not all smoothies are truly healthy—some can contain a lot of added sugar and sweeteners and if you’re having it pre-made somewhere, you don’t [always] know if they’re using unsweetened milk or what type of protein powder exactly of the portion size,” says Maggie Michalczyk, MS, RD.

It can be super confusing—smoothies are often seen as being packed with vitamins and minerals, as well as fiber and protein (if there’s a source like nut butter, milk, or avocado inside, and there usually is to make it creamy). And if you compared a smoothie to a bacon breakfast sandwich, you’re probably thinking that smoothie is the healthier option.

Yet smoothies can be surprisingly high in sugar and calories, thanks in part to their high concentration of fruit. Fruit is generally a healthy choice thanks to its antioxidants, vitamins, and fiber. However, fruit also contains natural sugars and carbohydrates, which can add up when you’re adding in several different kinds to a single smoothie. “Not knowing the portion size or the type of ingredients can unfortunately send you on a blood sugar roller coaster after you have a smoothie that you want to avoid,” Michalczyk says.

That blood sugar spiking effect can be compounded if additional sweeteners are added to the mix (something common at a lot of smoothie and juice chains). “It’s a good idea to avoid added sugars on top of the natural sugar that’s already in a smoothie from the fruit. Some places will add agave syrup, maple syrup or honey which is just unnecessary in my opinion,” she says.

Again, those natural and added sugars can really add up if you’re not careful. Just a small 16-ounce Mango-A-Go-Go smoothie at Jamba Juice, for example, contains 65 grams of sugar. (Sugar sources include mangos, a mango juice blend, and pineapple sherbet.) At Smoothie King, the Original High Protein Chocolate smoothie contains 34 grams of sugar in a 20-ounce serving. (The majority of that sugar comes from a serving of dates.)

Speaking of sugar, here’s the lowdown on how sugar impacts your body—and the healthiest possible alternatives: 

What does a healthy smoothie look like? Try this formula

Thankfully, making a truly healthy smoothie doesn’t have to be complicated. “I think one mistake is packing their smoothie with every ingredient under the sun. Simple smoothies can still be very nutritious and healthy and balanced so don’t feel like you have to add a ton of ingredients,” Michalczyk says.

Here’s her go-to formula for making the perfect balanced smoothie: 1 cup of greens (such as spinach or kale), a source of healthy fat (such as 1/4 avocado or a serving of nut butter), a source of protein (such as protein powder, chia or hemp seeds), then a source of carbohydrates such as berries, or bananas.

Your winning healthy smoothie formula = 1 cup greens + 1 healthy fat source + 1 protein source + 1 fruit

This combo will ensure that your smoothie is delicious and filling, without just being a sugar bomb that leaves you hungry an hour later. 

And don’t be afraid to get creative with what ingredients you use! Take a page out of Mark Hyman, MD’s book and use zucchini, almond milk, and berries as the core ingredients of your morning smoothie. Or use cauliflower (yes, really) to add some lower-sugar creaminess to your smoothies. You can also try experimenting with lower-sugar fruits to add sweetness without making your final product too sugary. “Even pumpkin puree works great in smoothies for a dose of fiber,” Michalczyk says.

How often to enjoy smoothies

If you do it right, every day. “I would say if you’re making a balanced smoothie that is low in sugar and providing your body with proper nutrition they can work for breakfast, a snack, and a post workout recovery drink,” Michalczyk says.

She particularly recommends them post-workout. “Because they are hydrating and usually packed with things that can help to replenish your electrolytes post-workout like banana, having [a smoothie] after a workout is a good idea,” she says. “Your body is craving energy to replenish with post-workout and a smoothie can have a pretty good carb-to-protein ratio, which is great for that,” she says.

However, Michalczyk recommends that the smoothies that might be a little more sugary, like those with more fruit in them than green veggies and protein powder or good fats, should be saved as an occasional treat.

“If you can when getting a pre-made smoothie, ask to see what brand of ingredients they use or how much of that they put into the smoothie. Don’t be afraid to ask for less or none of an ingredient. That’s the beauty of smoothies—they’re customizable,”she says.

On the subject of sugar, here’s why one RD hates the term “no added sugar.” And looking for other healthy breakfast ideas? Here’s what readers like you love to eat in the a.m.