Smoothies and Intermittent Fasting: What You Need to Know

by Shane Vaughan March 16, 2022

Intermittent fasting is one of today’s most popular wellness trends—and for good reason. Thousands of people around the globe are successfully using it to lose weight, improve their health, and simplify their lives.

In this article, we’ll be covering what you need to know about your intermittent fasting journey, including what it is, how to break your fast, and the role smoothies can play in intermittent fasting.

smoothie with healthy fat and minimal calories for optimal hydration

What Is Intermittent Fasting?

Intermittent fasting (IF) is not a diet in the conventional sense. It’s more accurately described as an eating pattern that cycles between periods of fasting and eating. It doesn’t specify which foods you should or shouldn’t eat, but rather when you should eat.

Anytime you’re not eating, you’re intermittent fasting. For example, most people have a fasting period between dinner and breakfast the next day, a period of approximately 12 hours. The term “breakfast” refers to the meal that you use to break your fast. In that sense, intermittent fasting is something that’s considered a part of everyday life.

What Are the Different Types of Intermittent Fasting?

There are three methods of intermittent fasting, which include:[*]

Time-restricted eating: This method involves eating only during a certain number of hours each day, often establishing a consistent daily pattern of eating within an 8-12 hour time window. Some approaches further restrict the time window, such as the 16:8 diet, which entails 16 hours fasting periods with an 8-hour eating window per day. This is the most common approach, with most of the fasting hours taking place overnight.
Alternate-day fasting: This method involves alternating between a 24-hour fasting window where a person eats less than 25% of their everyday energy needs, followed by a 24-hour non-fasting “feast day” period.
Periodic fasting: Also called whole-day fasting, this method involves a period of consecutive fasting of more than 24 hours. An example of this method is the 5:2 diet, which includes two fasting days per week and five days of normal eating. This method has much longer fasting windows.

What Happens in the Body During a Fast?

To understand how to practice intermittent fasting, you need to understand the role of insulin. Insulin is a hormone that regulates blood sugar. In response to eating, insulin is made in the pancreas and released into the bloodstream. Once released, insulin causes the body to store energy as fat. In other words, the more insulin that’s produced, the more fat you store.

During an intermittent fast, the periods when you are not eating give your body time to lower insulin levels, which reverses this process and stimulates fat burning.

Benefits of Intermittent Fasting

Unsurprisingly, weight loss is the most common reason people use intermittent fasting. A 2014 review study found that intermittent fasting can cause three to eight percent weight loss over three to 24 weeks.[*] Compared to other studies, this is significant weight loss.

The same study also found that participants lost four to seven percent of their waist circumference, suggesting a significant loss of belly fat. This is particularly notable, as belly fat can cause health problems, such as heart disease, diabetes, and liver problems.[*]

But the benefits don’t stop at weight loss. Research suggests that intermittent fasting can also reduce insulin resistance, improve heart health, reduce inflammation, and support brain health.[*][*][*][*] In animal studies, intermittent fasting has even been shown to extend lifespan and prevent cancer.[*][*]

Another, often overlooked, benefit of intermittent fasting is increased time and productivity. When fasting, time that’s usually spent preparing meals and eating can be redirected to other activities.

gently break plate no artificial sweeteners with hunger pangs

What Breaks a Fast?

Many people are confused about what they can and cannot consume while fasting. Some people mistakenly think that because smoothies are liquid, they can be consumed during a fast, but this is not the case.

Any amount of consuming calories disrupts the fasting process. If you’re adhering to a strict fasting window, that means you should avoid any foods or drinks containing calories, including smoothies, fruit juice, and bone broth. No- or extremely low-calorie beverages, including water, black coffee, tea, and other zero-calorie beverages are permitted during a fast.

Diet sodas, even though calorie free, are a point of contention, consult with your doctor. Apple cider vinegar is known as one of the "healthy foods" and is typically OK given its calorie count while fasting, though it's recommended to use diluted apple cider vinegar.

first meal to up energy levels and break intermittent fasting

Breaking Your Fast With a Smoothie

While smoothies can’t be consumed during a fast, they make an excellent tool for breaking a fast. Let’s discuss why that is.

When it comes time to break your fast, the key is to ease back into eating to reduce digestive and blood sugar stress on the body. Foods and beverages high in protein and fats are ideal, as they’re low sugar and calorie-dense. These macronutrients will help you feel full without overwhelming your digestive system.

Low glycemic foods and drinks are another good option, as they can also help you feel full without overwhelming your digestion or negatively affecting your blood sugar. Good low glycemic options include non-starchy vegetables, some fruits, and sweet potatoes.

Smoothies are the perfect tool for gently breaking a fast. When prepared correctly, they can help satiate you, boost your energy, and balance your blood sugar. Because they’re blended, they also tend to be easier to digest.

Avoid including too much fruit or other high-carb ingredients in your smoothie, as these will cause a blood sugar roller coaster, raising your insulin levels and making you feel unwell and hungrier. Instead, pack your smoothie with plentiful fat and protein, a good dose of non-starchy veggies, and some low-sugar fruits. The best smoothie to break intermittent fasting is simple, healthy and easy on the digestive system.

Blendtopia offers several frozen, pre-portioned smoothie kits that are brimming with healthy fats, protein, organic frozen fruits and veggies, and other nutritious superfoods.

In particular, our three keto smoothie options—Keto Green Smoothie, Keto Berry Smoothie, and Keto Chocolate Chai Smoothie—are ideal for breaking a fast, as they supply a hearty dose of fat, protein, and fiber, all of which can help fill you up without overwhelming your digestive system.

caloric beverages for metabolic health and insulin sensitivity with few calories

All you have to do is pour the contents of the smoothie pouch into your blender, add 12-14 ounces of liquid (such as plant milk or water), and blend it up!

Other Tips for Breaking Your Intermittent Fast

In addition to breaking your fast with a low glycemic liquid meal, such as a smoothie, here are some other helpful tips for reintroducing food:

Avoid processed foods
Stick to small portions
Take a probiotic before your meal
Consume your meal slowly and mindfully
If breaking your fast with a smoothie, consider adding protein powder for the health benefits

You Shouldn’t Fast If…

If you’re pregnant or breastfeeding intermittent fasting is a no no. Fasting promotes fat burning and when you’re pregnant or breastfeeding you should be storing fat, not burning it. You should also avoid fasting if you have history of an eating disorder. The goal of fasting is improved overall health but for those who have struggled with an eating disorder, fasting can act as a trigger for relapse.

Again, we can’t emphasize enough that it’s always a good idea to consult a physician before embarking on a new alternative eating lifestyle that your body has never experienced before.

The Bottom Line

Ultimately, the best eating pattern is the one you can stick to long-term. If you feel good when practicing intermittent fasting and find it to be sustainable, it can be a powerful tool to lose weight, improve your health, and boost productivity.