Smoothies: Are They Good for You?

Medically Reviewed by Jabeen Begum, MD on November 28, 2023
Written by Katie Cameron
6 min read

A smoothie is a thick beverage made by mixing fruits, vegetables, and other ingredients in a blender.

Common smoothie ingredients

Based on your preferences, healthy additions to a smoothie can include:

  • Fruits like apple, mango, banana, avocado, or pineapple
  • Other vegetables like carrot, beetroot, cucumber, or cauliflower
  • Nuts and seeds like almond or peanut butter, hemp or chia seeds, and flax meal
  • Herbs and spices like ginger, cinnamon, turmeric, or cocoa powder
  • Natural sweeteners like honey, dates, or Stevia
  • Creamy additions like yogurt, dairy or nondairy milk, or silken tofu

Smoothies are also an easy way to take supplements like protein powder, spirulina, or other powdered vitamins and minerals just by adding a serving to the blender. 

Green smoothies are nutrient-rich blends of fruits and vegetables. They’ve become a popular way for people to meet their recommended daily intake of vitamins and minerals. Unlike juices, green smoothies retain the beneficial fiber content from whole foods.

At their most basic, green smoothies combine leafy greens like spinach, kale, arugula, and microgreens with a base liquid like water. While these greens alone can make for a bitter-tasting smoothie, there are tons of combinations that improve its flavor profile and add nutrition. 

The nutritional value of a smoothie can change drastically based on the ingredients used to make it. Smoothies made with whole-milk yogurt, for example, will have more fat than smoothies made with water or nonfat yogurt. Smoothies made with milk, yogurt, or water will have less sugar than those made with fruit juice. Here are some examples of brand-name smoothies and their unique nutritional profiles. 

Small Baskin-Robbins fruit cream strawberry smoothie: 

  • Calories: 530
  • Fat: 15 grams
  • Cholesterol: 0.055 gram
  • Sodium: 0.29 gram
  • Carbohydrates: 90 grams
  • Fiber: 2 grams
  • Sugar: 85 grams
  • Protein: 12 grams

Strawberry banana V8 smoothie: 

  • Calories: 91
  • Fat: 0 grams
  • Cholesterol: 0 grams
  • Sodium: 71 micrograms
  • Carbohydrates: 20 grams
  • Fiber: 0 grams
  • Sugar: 18 grams
  • Protein: 3 grams

Yoplait strawberry swamp smoothie:

  • Calories: 120
  • Fat: 1 gram
  • Cholesterol: 0.05 gram
  • Sodium: 0.9 milligram
  • Carbohydrates: 23 grams
  • Fiber: 0 grams
  • Sugar: 20 grams
  • Protein: 4 grams

As you can see, despite all of these foods being marketed as strawberry smoothies, the nutritional profile of each is vastly different. It’s important to read the label on a smoothie to determine its nutritional value before making a purchase. 

When making your own smoothies, measure your ingredients, calculating your calories and nutrients before putting anything into the blender. That way, you know exactly what your nutritional profile will look like and can make the best decisions about what to include. 

To limit the amount of sugar in your smoothie, consider making one at home. If you make your own green smoothie, its nutritional content will vary based on what you include.

Green smoothie nutrition:

As a baseline, an 8-ounce serving with a half-cup each of spinach, kale, apple, and banana contains: 

  • Calories: 120
  • Protein: 3 grams 
  • Fat: 0 grams
  • Carbohydrates: 30 grams 
  • Fiber: 5 grams 
  • Sugar: 15 grams 

This combination is a good source of: 

Green smoothies are also a great source of B vitamins. The B vitamins found in leafy greens, like folate, vitamin B6, and niacin, help your body release energy from food and can promote a healthy nervous system.

There are many health benefits of smoothies. If you’re the type of person who’s content replacing a meal with a smoothie, you may benefit from adding more of these blended beverages to your life. Before you make any changes to your diet, discuss them with your doctor.

Here are some other upsides to smoothies: 

You can get more fruits and vegetables

One great trait of smoothies is that you can sneak almost any fruit and many vegetables into them while still making them taste good. Studies show that eating enough fruits and vegetables each day reduces the risk of chronic diseases and helps you maintain a healthy body weight. But many people don’t meet their daily recommended intake of fruits and vegetables.

If you’re one of the many people who struggle to eat enough fruits and vegetables each day, adding smoothies to your diet may help. One smoothie can have two to three servings of fruits or veggies packed inside, making it easier to meet the mark. 

Increased fiber intake

Although the U.S. Department of Agriculture (USDA) recommends 25 to 38 grams of fiber a day, the average American is only taking in about 16 grams a day. This is a big deal, as poor fiber intake is linked not only to poor digestion but also to chronic illnesses like type II diabetes and heart disease.

Because smoothies are loaded with fruits and vegetables, they also tend to be loaded with fiber. This can help bridge the gap between your normal fiber intake and the USDA’s suggested fiber intake, lowering your risks of chronic illnesses and improving your overall health. Fibrous foods can also help you feel fuller for longer, which can help you meet weight loss goals.

Better bone strength

The leafy greens like kale and spinach in green smoothies are a great source of vitamin K1. Research has shown that people with a high intake of vitamin K1 are have a lower risk of bone fractures, osteoporosis, and decreased bone mineral density. 

May support immunity

Leafy greens are much higher in vitamin C than other vegetables. Vitamin C is known to support the immune system, fight infection, and help maintain healthy cellular function throughout our bodies, making these greens a nice addition to any smoothie. 

May lower risk of chronic disease

Antioxidants like beta carotene and vitamin C, which help to prevent and may even reverse oxidative damage caused by free radicals, can be found in leafy greens. Free radicals occur naturally but can increase in the body due to lifestyle and environmental factors, and the damage they cause to our cells is linked to chronic issues like inflammation, heart disease, and cancer. 

Help lower cholesterol

Bile acid sequestrants are compounds used in medicine to lower cholesterol and are found naturally in leafy greens – and the smoothies you make with them. Maintaining healthy cholesterol levels keeps fatty deposits from building up on your artery walls, reducing your risk of heart disease. 

For the most part, if you use a smoothie to replace a meal, you’ll be fine. The biggest problem with smoothies stems from using them alongside meals to replace what you drink. This can lead to eating too many calories overall throughout the day. And for some people, smoothies can aggravate other issues:

Higher blood sugar levels

Added sugars in your already-sweet smoothies can be especially bad for your body, and should be avoided if possible. But even if you’re making your smoothie yourself using all-natural ingredients, it can still have a lot of the natural sugar in it. After all, fruit is high in sugar, and smoothies contain a lot of fruit.

People with type II diabetes and other conditions that make sugar risky should be careful about consuming smoothies. 

Weight gain

Leafy greens are naturally low in calories and fat. But common smoothie additions like fruits, nut butters, sweeteners, or milks can add excessive amounts of these nutrients to a single serving. Too much fat or too many calories can lead to unwanted weight gain, so measure your portions so you know what’s in your drink. 

Medication interference

The high vitamin K content in leafy greens can reduce the effects of certain anticoagulant drugs. While people taking blood thinners don't need to avoid vitamin K, you should still talk to your doctor about how much you should consume.