Could a Smoothie Diet Help You Lose Weight (& Is It Keto-Compatible)?

Jun 9, 2023
Anna Paula Auziņa
, nutritionist
What you’ll learn

    You’ve got a big event coming up, but your slinky black dress is still just a little too tight. Your usual routine of eating healthily (most of the time) and counting calories just isn’t getting you to your goal weight fast enough. And you don’t want to have to leave your gorgeous dress hanging in your wardrobe yet again.

    Could a smoothie diet be the solution you’re looking for?

    Smoothie diets have become hugely popular — but do they work? This article will dig into how smoothie diets can help you lose weight, whether they’re safe, and how to make smoothies keto-friendly.

    What is a smoothie diet, and does it work?

    A smoothie is a blended drink with fruits, vegetables, and other ingredients like almond milk or yogurt. Depending on the recipe you follow, a smoothie can be a full meal replacement, a snack, or a supplement. Standard smoothie recipes will differ from keto-friendly recipes, which are low in carbs.

    Smoothies can be a great source of fiber and nutrients in a wide range of flavors. Think of it as a way to eat your fruits and veggies in a convenient, delicious meal you can take on the go. As for whether smoothies can help you lose weight, the answer is yes — but only if done correctly.

    What is a smoothie diet?

    A smoothie diet involves replacing one or more meals with a smoothie each day. Some smoothie diets are designed to take place for just a few days, with all meals replaced with smoothies. Others can be followed for longer, with smoothies replacing only one or two of your daily meals.

    Are smoothie diets effective?

    Smoothie diets can be effective, at least for some people. In a study where participants were asked to replace their breakfast and lunch with a beverage and follow an appropriate calorie-restricted diet, overweight and obese adults — 42 females and 13 males — who had a mean weight of 206 lbs and a BMI of 32.7 lost an average 4.8% of their total body weight.

    Image of a person holding a smoothie and smiling

    Adding smoothies to your diet can also help you increase your fruit intake (though if you’re following a keto diet, you’ll need to be careful to choose low-carb fruits). A study of middle and high school students at two schools offering fruit smoothies for breakfast found that the percentage of students eating a full serving of fruit at breakfast increased from 4.3% to 45.1%.

    Plus, a recent study has shown that smoothies containing berries such as blackberries and raspberries resulted in lower blood sugar levels than consuming them as whole fruits. Researchers believe that the additional fibers released from blending contributes to this effect. So, there are multiple benefits to adding smoothies to your diet.

    Are smoothies compatible with keto diets?

    Smoothies are compatible with a keto diet as long as they utilize low-carb ingredients, like avocado, unsweetened coconut milk, spinach, frozen berries, and proteins like Greek yogurt. You’ll need to be careful to avoid high-carb fruits and added sweeteners in your smoothies if you’re trying to stay in ketosis — but with a little bit of creativity, it can be done! It will all come down to your preference for what flavor combinations you enjoy.

    Tips for transitioning to a smoothie diet

    If you're considering a smoothie diet, here are some tips for making the transition easier:

    Start slow

    A smoothie diet is not intended to be an all-or-nothing type of endeavor, as this can be unsustainable over time. This type of diet is only designed to have one or two daily meals replaced by well-balanced smoothies rather than every meal.

    You don't have to jump in head-first, either. Start with a smaller goal, like drinking one smoothie three days per week. Then, as you get more comfortable in the routine, you can increase the number of days you plan to drink a smoothie.

    Choose high-quality ingredients

    The quality of the ingredients that go into your smoothies is just as important as the number of servings. Choose organic ingredients whenever possible, and choose low-sugar fruits like blueberries or strawberries when you can.

    Additionally, adding protein and healthy fats like nuts, nut butter, avocado, coconut oil, or chia seeds can help to keep you full for longer. This can help you avoid snacking on unhealthy snacks between meals, resulting in a lower daily calorie intake.

    Image of a blender and various veggies/fruit and almond butter or chia seeds being measured and prepared for a smoothie.

    Experiment with flavors

    If you’re planning to drink smoothies as a meal replacement each day, chances are you’ll grow tired of drinking the same flavor every day. To combat this, try experimenting with different flavor combinations and ingredients to keep your taste buds excited about your smoothie selection.

    Remember, you're on a journey.

    Whatever your goals are regarding smoothie dieting, it's important to remember that the results won't happen overnight. It takes time and dedication to make healthy changes, so be kind to yourself and remember that you’re on a health and wellness journey. Celebrate even the little victories along the way and be proud of yourself for every step you take towards reaching your goals.

    Are smoothie diets safe?

    Generally, smoothie diets are a safe way to lose weight and improve your diet. However, as with any diet, following safety guidelines is key. Avoiding added sugars, artificial ingredients, and low-quality ingredients is vital to ensure that you’re getting the most nutrient-dense smoothies.

    Additionally, if you’re planning to replace meals with smoothies, it is essential to ensure that you still get the proper balance of macronutrients. Aim to include a source of protein, healthy fats, and fiber in your smoothies. Be sure to consult with a dietician to check if any supplements might be useful for you on this diet.

    Let's look at some of the risks associated with incorrectly following a smoothie diet:

    Hunger and cravings

    If your smoothie meals are not properly balanced in terms of macronutrients, you may find yourself struggling with hunger and cravings during the day. This can lead to overeating and binging, which will defeat the purpose of your diet.

    It's also possible that replacing too many meals with smoothies may cause too low of a caloric intake, leading to feelings of sluggishness and fatigue.

    Excessive sugar consumption

    Drinks marketed as smoothies can be very high in sugar, potentially leading to increased blood sugar levels. Even if you’re making your own smoothies, you need to be mindful of the sugar content of the fruits you use. This is especially crucial if you’re following a keto diet and thus keeping your carbohydrate intake very low.

    Fruits that are high in sugar

    High-sugar fruits to limit (or avoid altogether if you’re following a keto diet) include tangerines, cherries, grapes, figs, pomegranates, mangoes, and bananas.

    Risk of nutritional deficiencies

    Diets that replace too many meals with unbalanced smoothies can also lead to nutrient deficiency risks. Store-bought or premade smoothies that use fruit juices and purees rather than whole fruits lose some of the nutritional health benefits of fruits, such as fiber, phytonutrients, vitamins, and minerals.

    You should be aware of the risk of nutrient deficiencies if you plan to replace more than one meal a day with smoothies. It's crucial to ensure that the smoothies you make or purchase are well-balanced and provide enough calories, protein, healthy fats, vitamins, and minerals to meet your dietary needs.

    Certified Keto Diet customized meal plans have smoothie recipes that align with the dietary guidelines of a Keto diet, so you can feel good about what you’re drinking.

    Steps to start a smoothie diet

    1. Decide how many meals to replace with smoothies

    When starting a smoothie diet, it's best to analyze your health and wellness goals to determine how many meals per day you should replace with smoothies. If weight loss is your goal, replacing one or two meals with smoothies can help you reduce your caloric intake.

    Your other meals and snacks should combine to give you a healthy, balanced diet. Drinking a smoothie for breakfast and another for lunch won’t result in weight loss if you eat lots of fast food for dinner and constantly snack on high-sugar treats.

    2. Prepare your shopping list

    It’s best to make your own smoothies instead of using store-bought ones. By making your own, you can make them as healthy as you’d like.

    Good low-sugar fruits to use in your smoothies include:

    • Blackberries
    • Strawberries
    • Blueberries
    • Raspberries
    • Starfruit
    • Tomatoes
    • Avocados

    You’ll also want to include a protein source, like yogurt, kefir, or milk, along with healthy fats like flax seeds, chia seeds, avocados, nuts, coconut oil, or low-carb nut butter. And don’t be afraid to add vegetables. Kale, spinach, and other leafy greens make great additions to a traditional fruit smoothie.

    A list of low-sugar keto fruits

    Avoid using smoothie ingredients that have a lot of added sugar, such as ice cream, frozen yogurt, honey, and agave.

    3. Make your smoothies

    Got your ingredients ready? It’s time to blend up those smoothies! To get your smoothie nice and smooth, add the liquid first, then the greens, and add the frozen fruits/veggies and other solids last. Start your blender at low power, then gradually increase the speed. You’ll get a smoother smoothie by blending at a low speed for longer.

    Some people prepare a week’s worth of smoothies in advance, while others prepare them daily. Freezer packs with all of the ingredients (minus the liquid) can be a helpful way to save time when making smoothies daily.

    3 great keto smoothie recipes to try out

    Ready to give some smoothie recipes a try? We’ve picked some delicious keto smoothie recipes that you could choose as part of your smoothie diet. The best thing about smoothies is how customizable they are, meaning you can switch out ingredients to make them work for your taste or dietary needs.

    1. Strawberry avocado keto smoothie

    A refreshing strawberry avocado smoothie is an excellent choice if you're looking for a smoothie perfect for the summer months. All you have to do is pick a base of unsweetened almond or coconut milk, add a handful of spinach, half an avocado, and frozen strawberries. Blend all the ingredients together and enjoy!

    If you need a little extra sweetness, monk fruit extract is perfect for adding a touch without any additional carbs or calories. This smoothie is a tasty way to get your daily intake of healthy fats and fiber, and it is a beautiful pink color, too.

    2. Keto peanut butter smoothie

    One of the most versatile smoothies you can make is the peanut butter smoothie. There are countless variations you can create, but this one is a great start. Begin with a base of ice, unsweetened almond milk, natural peanut butter (no sugar added), unsweetened cocoa powder, and the keto-friendly sweetener of your choice (one popular option for this smoothie is erythritol).

    Image of a keto peanut butter smoothie

    Blend all the ingredients until it is a creamy, rich smoothie packed with healthy fats and protein. It's a great way to indulge your sweet tooth without spiking your blood sugar levels.

    3. Keto blueberry smoothie

    Try a blueberry coconut smoothie if you're looking for a fresh, tart flavor. This recipe utilizes unsweetened coconut milk as the base, combined with frozen blueberries, unsweetened coconut milk yogurt, and vanilla extract. Blend all the ingredients until you see a creamy, bright smoothie.

    The blueberries in this keto blueberry smoothie make it a fantastic source of antioxidants, folate (vitamin B9), and vitamin C, and it’s incredibly simple and quick to make. For an added boost of healthy fats and protein, toss a tablespoon of chia seeds or MCT oil. This will help you feel full and energized for hours. This smoothie is excellent for a healthy snack or breakfast without added sugar.

    These are just a quick selection of some delicious keto smoothie recipes you can try. Remember to keep your ingredients low-carbohydrate, low-sugar, and high-fiber to keep your body in ketosis. Always measure your fruit to ensure you are not exceeding your daily amounts of carbohydrates. Additionally, find a balance of fats and proteins that works for you. With the right ingredients, smoothies can be a great way to help you reach your health and weight loss goals. Celebrate your success when you reach your goals, and be sure to enjoy the entire journey.

    Get customized smoothie recipes with CertifiedKetoDiet.

    Smoothies can be an ideal way to get more fruit and veggies into your diet, and you can absolutely enjoy them on a keto diet plan.

    You can eat a breakfast smoothie daily or replace a couple of meals with smoothies to help with weight loss.

    Not sure what ingredients might work best or whether a smoothie diet is right for you? Our team of experienced nutritionists can create a keto meal plan customized to your needs. Get started with the Certified Keto Diet quiz today.

    Let's see how Certified Keto Diet can help you!