Are Smoothies Healthy? Here’s What the Experts Say
Smoothies have a health glow about them. They’re often an integral part of cleanses, and they’re ubiquitous at health food stores and health-centric restaurants. And the smoothie trend is still going strong. Workout studios serve them up post-class, dietitians preach their powers and fit celebrities tout their nutritional prowess.
But are smoothies healthy? Here’s what you should know about the drink, whether you’re picking one up or making your own.
- How to make healthy smoothies
You can put nearly anything into a smoothie. But most consist of liquid (like water, non-dairy milk or kefir), fruits, vegetables, seeds, nuts (or nut butter), supplements like protein powder, maca or matcha, and toppings (such as granola, coconut and cacao nibs), says Ryan Andrews, a registered dietitian and author of A Guide to Plant-Based Eating.
The key to making it healthy is to strike the right balance of vegetables, fruit, protein and fat, says Miranda Hammer, a registered dietitian and natural foods chef based in New York. “The smoothie is a really great way to get in those key foods,” Hammer says. When you make this type of smoothie, “you have the foundation for a healthy breakfast or snack.”
Protein can come from unsweetened nut butter, chia, hemp or flax seeds, plain yogurt or nut milk. And fat, which helps fill you up, is the other key factor in a smoothie. “Good sources of fat in smoothies are salt and sugar-free nut butter, chia, flax, sesame, or hemp seeds, flax oil, coconut meat, coconut yogurt, or full-fat organic yogurt,” Hammer says.
For an additional nutritional boost, she recommends adding ingredients such as maca, acai powder, lucuma, cacao, spirulina, herbs like cilantro or parsley and spices like cinnamon, nutmeg, ginger or turmeric.
And do embrace variety. “Try to mix up the ingredients. Dietary diversity can be really helpful to ensure a well-rounded nutrient intake,” Andrews says. If you use kale, kefir and blueberries one week, for instance, try spinach, hemp milk and pineapple the next.
- Are fruit smoothies healthy?
While fruits have antioxidant and anti-inflammatory benefits, smoothies often become hyper-concentrated sources of fruit sugars, Andrews says. Balance it by adding a dark leafy green like spinach, kale or Swiss chard (which provides fiber, calcium, vitamins A, C and K, as well as powerful phytochemicals) and protein to keep blood sugar in check and control cravings and hunger.
Just beware of the smoothies you buy. “With store-bought smoothies, you lose total control over quality and quantity of the ingredients used,” says Hammer. Store-bought varieties may use artificial sweeteners, fruit juice, large amounts of fat or sweetened dairy products, contributing to higher amounts of sugar, fat and calories. Smoothie bowls can also contain large amounts of sugary granola and sweetened coconut flakes, she says.
“Once in a while, these aren’t a major concern,” says Andrews. But if these types of smoothies are in your regular rotation, they could lead to excessive sugar intake or digestive distress, he says.
- Are green smoothies healthy?
Yes. One of Hammer’s rule is that all of her smoothies include a dark leafy green like spinach, kale or Swiss chard, which provides fiber, calcium and vitamins A, C and K, as well as powerful phytochemicals.
Green smoothies are a great way to get much-needed vegetables. Only 9% of Americans get the recommended daily amount of vegetables (2 to 3 cups), despite research suggesting that plant-based diets reduce the risk of chronic disease and cancer.
Green, leafy vegetables in particular are linked to a lower risk of developing type-2 diabetes, as well as slower age-related cognitive decline. A handful or two of greens usually makes for the best-tasting smoothie.
- Are smoothies good for weight loss?
Smoothies are often touted as a diet food and a way to detox the body. But when it comes to the idea of a “detox,” most experts agree that smoothies (or any other food, for that matter) aren’t the solution - and that the human body has its own resources (namely the liver, kidneys and GI system) to cleanse itself naturally. There’s also no solid scientific evidence to suggest the idea of a detox for overall health or well-being.
As for weight loss, instead of focusing on dieting - and what foods might be a part of that diet - it’s best to consider all of the behaviors that support a healthy body, says Andrews. Drinking smoothies could fit as one of those weight-loss behaviors, along with eating a balanced diet, getting plenty of physical activity, ensuring adequate sleep, building social connections and practicing stress management. But it’s not the only part of the puzzle.
- Can a smoothie replace a meal?
While eating a smoothie as a meal could be a healthy option, in order to make it nutritious, it’s important to make sure the smoothie contains a mix of foods that would be similar to a meal, says Andrews. “If someone just blends up some fruit, I wouldn’t say that’s an adequate meal,” he says. But add vegetables, seeds or nuts, kefir or yogurt and possibly some protein powder, and “this would be similar to foods that make up a meal.”
A well-rounded smoothie usually has 1 to 2 tablespoons of fat, 1 cup of fruit, a handful or two of greens and 1 cup of protein, Hammer says. How much you eat depends on what else you’re eating that day, as well as how you’re eating your smoothie - as a meal or as a snack - notes Andrews.
To make one of Andrews’ favorite breakfast smoothies, combine 1 cup frozen blueberries, 1/2 frozen banana, 1/2 cup frozen cauliflower, 1 to 2 leaves of kale, 1 to 2 cups of unsweetened non-dairy milk, 1 to 2 spoonfuls of mixed seeds (chia, hemp, flax), 1 scoop hemp protein powder and some granola.
- What’s the healthiest way to eat a smoothie?
“When you are eating a fruit or vegetable in its whole original form, your body is breaking everything down itself,” says Hammer. Digestion starts with the process of chewing, adds Andrews. Smoothies don’t involve chewing. Essentially, the blender does the chewing for you, he says.
That means some people might notice that they feel a little bloated when they drink a smoothie quickly. Smoothies can have a lot of calories, Andrews says, and the more calorie-dense a beverage is, the longer it will stay in the stomach, he says. To help slow you down, Andrews suggests eating a smoothie with a spoon, like you would a whole-food meals.