By Colleen D. Webb, MS, RDN
People who eat a variety of fruits and vegetables live longer and better lives. Fruits and veggies have vitamins, minerals, fiber, and powerful anti-inflammatory agents that protect us from chronic disease. Yet, most of us eat too few fruits and vegetables. And those of you with Crohn’s or ulcerative colitis might intentionally avoid fruits and vegetables because of their fiber.
Smoothies and juices are two gut-friendly ways to eat more fruits and vegetables on a low-fiber diet.
In this post, we answer your most popular questions about juices and smoothies for IBD.
Table of Contents
What’s the difference between a smoothie and juice?
A smoothie comes from pureeing fruits, vegetables and other wholesome foods in a blender. Blenders break down the tough fiber without removing it. The final product is thicker than juice.
A juice comes from separating the liquid from fruits and vegetables in a juicer, also known as a juice extractor. Unlike blenders, juicers remove the fiber and pulp.
Recall that dietary fibers are non-digestible carbohydrates found in plants. Humans can’t break down fiber more than we can chew it, so it travels throughout and exits the gastrointestinal (GI) tract more or less the way it came in. Some high-fiber foods, like fresh fruits and veggies, can lead to GI upset in people with IBD and other GI conditions. That’s why many people with IBD follow a low-fiber diet.
Both smoothies and juices are appropriate for a low-fiber diet. You need not cook fruits and vegetables before blending or juicing them.
Are juices more or less nutritious than smoothies?
There’s no simple answer to this question. Smoothies and juices have distinct health benefits based on their inclusion and exclusion of fiber.
Juices and Smoothies Compared
Compared with juices, smoothies …
- are more likely to satisfy and energize us over longer periods of time.
- are less likely to spike blood sugar.
- are more likely to feed beneficial gut microbes.
- can provide important nutrients found in the skins of fruits and vegetables
Compared with smoothies, juices …
- can pack more vegetables into the same serving size.
- can provide faster and easier access to key nutrients.
Fiber aside, the nutritional value of a juice or smoothie will depend on what’s in it.
What kinds of GI symptoms can I expect?
Even though smoothies and juices are relatively gentle on the GI tract, they can produce unwanted side effects in some people.
Those sensitive to FODMAPs might experience more gas, bloating, and/or diarrhea after drinking a smoothie or juice.
Juices, more so than smoothies, can have a laxative effect. That’s why I regularly recommend them to my patients with constipation.
Also, temperature matters.
Scott says: Be careful with cold juices and smoothies. Having grown up in Houston I spent a lot of time in brutal heat where a glass of glorious ice cold water was a welcomed relief, or so I thought… Turns out that drinking cold liquids can cause GI distress for many people with IBD. That was my case, and it could be yours.
What about juice cleanses for someone with IBD?
While I encourage some people with IBD to include vegetable juices as part of a healthy diet, I don’t support juice cleanses. Consuming nothing but juice for a few days can be dangerous. I’ve worked with people with Crohn’s and ulcerative colitis who have flared just a few days into a juice cleanse. Coincidence? Maybe. But, here are three reasons you might want to steer clear of juice cleanses:
- They can interfere with your body’s own detoxification process or ability to excrete toxins.
- They lack protein and your gut needs protein to function well and protect you against environmental toxins.
- They may lead to rapid weight loss and electrolyte imbalances.
What fruits and vegetables should I use?
There are no hard and fast rules for what fruits and vegetables you should or shouldn’t use. A healthy diet is full of variety. When you’re feeling well, aim to include every color of the rainbow. But be sure to emphasize veggies over fruit. Add beets and carrots for a touch of sweetness.
For smoothies, a useful rule of thumb is a 2:1 ratio of veggies to fruit. For juices, stick to 1-2 half-servings of fruit plus 2 or more servings of vegetables.
Test different flavor combinations. What you like might surprise you.
- Both juices and smoothies are suitable for a low-fiber diet.
- You don’t have to cook fruits or vegetables before blending or juicing them.
- Making homemade juices or smoothies is an excellent way to use up leftover vegetables.
- You can add a salad’s worth of greens to a smoothie or juice.
- Smoothies and juices are portable.
- Both juices and smoothies are good options when you don’t have the time or effort to focus on chewing your food.
- Experiment with different flavor combinations until you find ones you enjoy. Scott’s go-to juice includes cabbage, beets, spinach, kale, Swiss chard, ginger, carrots, and cucumber. This might be too bitter for other folks, but it works for him.