10 Tips for Going on a Liquid Diet

• People with Crohn's disease often struggle to digest food, particularly when symptoms flare up. Sometimes a liquid diet is the answer.
• "If you have a hard time maintaining your weight with regular food, whether it's because you have diarrhea or a poor appetite, I absolutely recommend drinking calories, sort of in combination with food," says Tamara Duker Freuman, a registered dietitian in New York who specializes in digestive disorders.
• However, check in with a doctor or dietitian before going on a solely liquid diet (anything more than a meal or two).

Even if your Crohn’s disease symptoms are under control, you may still have trouble keeping on weight.

If so, have a bottle of Ensure or Boost along with meals or make yourself a drink that has 200 to 300 calories, Freuman says.

She adds that Ensure and Boost, which deliver about 250 calories per serving, would probably be your first choice if you tolerate them because they are relatively inexpensive, sold everywhere, and nutritious.

Liquid meals can be lifesavers during flare-ups, when symptoms like diarrhea, cramping, and constipation are at their worst.

“You’re going to see improvements in symptoms…your bad days will be easier with liquid meals,” says Martha Rosenau, a registered dietitian and owner of Peak Nutrition, based in Colorado Springs, Colorado.

Rosenau recommends consuming as many calories, either as liquids or solids, as you can tolerate during flares.

Making your own liquid meals can save money and be convenient if you make a batch and save it in the fridge.

Rosenau recommends this easy smoothie recipe: Blend milk (if you can tolerate it), or almond or soy milk if you are lactose intolerant, with yogurt or soy yogurt, protein powder (soy, egg, or whey), and a banana.

But there’s no need to slave over a blender if you’re not into it. Just buy liquid meal replacers instead, Rosenau says. “There is no nutritional benefit to making your own.”

“One thing across the board that would be true of almost everyone who has Crohn’s disease is that they are unlikely to tolerate dairy products in a flare,” Rosenau says.

If that’s true for you, skip milkshakes or Carnation Breakfast Essentials, which contains nonfat milk, and go for Ensure or Boost, which contain milk protein but not lactose. Or you can make smoothies with lactose-free dairy or soy products.

After a flare, try to reintroduce dairy such as yogurt, to see if you can tolerate it, Rosenau says.

Sugar is probably not going to be your friend during a Crohn’s flare. “It literally pulls water into your bowels and contributes to diarrhea,” Freuman says.

Look for liquid meals that contain calories from fat and protein so you know that not all the calories are coming from sugar.

If you are making your own smoothies, plain coconut water is a good low-sugar source of electrolytes and vitamins, Freuman says.

Sugar-free products are not necessarily diarrhea-free, Freuman points out. They often contain sugar alcohols that can make diarrhea worse. (Look for ingredients like mannitol, sorbitol, and xylitol.)

The same is true for Splenda, which can aggravate symptoms in some people, while Nutrasweet tends to be more tolerable for people with Crohn’s disease, Freuman says.

Vitamin deficiencies can plague people with Crohn’s, depending on the location and severity of their disease.

People often have vitamin B12 and vitamin D deficiencies, especially if the disease affects the ileal or lower section of their small intestine, as is often the case, says Stephen Hanauer, MD, chief of gastroenterology, hepatology, and nutrition at University of Chicago.

Damage higher up in the small intestine is associated with deficiencies in zinc, iron, and B vitamins.

When it comes to liquid meals, taste and tolerance vary between people almost as much as Crohn’s disease itself, Dr. Hanauer says.

You might find that brands like Ensure or Boost upset your stomach, or you don’t like the taste. “I hear from a lot of people that they’re intensely sweet,” Rosenau says.

Luckily, there are other options in your grocery or natural foods store. Rosenau says that some of her clients do really well with Mix1 protein shakes and GoodBelly juices, which are dairy-free and contain probiotics.

It can be a challenge to spark your appetite, especially if you are limited to liquid meals.

Soups can be a nutritious, savory break from sweet smoothies. “Anything that’s broth based is good, like tomato soup, chicken, turkey, or fish broth,” Rosenau says. High-fat creamy soups may worsen diarrhea and constipation, however.

Try adding peanut butter, frozen peaches, or mango chunks to smoothies. Peanut butter, unlike whole peanuts, is low-residue, and fruits that have been frozen tend to be more digestible.

A common dietary tip for people with Crohn’s disease is to chew your food well.

“I tell my patients with Crohn’s they need to change religions and covert to ‘Chew-daism,’” Dr. Hanauer says. “Digestion begins in the mouth.”

You can also make solids easier to digest by cooking them well—think mushy, boiled vegetables or rice. These steps can make the solids you eat (or reincorporate after a flare) go down almost as smooth as the liquids.