What Is the Clear Liquid Diet: What to Eat and What to Avoid

If you've been told to follow a clear liquid diet, you may be wondering what that means and what foods (if any) it includes. But it's not as tricky as it sounds. "A clear liquid diet is a diet made up of only clear foods or liquids, meaning you have to be able to see through it," says Lisa Andrews, M.Ed., RD, LD, owner of www.soundbitesnutrition.com. A clear liquid diet is usually prescribed before or after surgery, for colonoscopy prep or to treat severe gastrointestinal distress. This article will walk you through what to expect if you're told to stick to clear liquids, including what you can and cannot eat and the associated risks of this restrictive diet.

What Is a Clear Liquid Diet?

"A clear liquid diet is a short-term diet that consists of easily digestible liquids," says Patricia Kolesa, M.S., RDN. Clear liquids require minimal digestion, which gives the bowels a rest in anticipation of a medical event. "It's used when an individual needs to limit digestion or absorption of nutrients, often before or after surgery or possibly for colonoscopy preparation," says Andrews. The purpose of a clear liquid diet is to provide fluids and some nourishment without overwhelming the bowels.

Clear Liquid Diet Foods List

True to its name, the clear liquid diet consists of liquids that are see-through at room temperature. This can be a bit tricky, since certain foods are only allowed in specific flavors, like light-colored Jello versus red, or black coffee instead of milky coffee. Here's a full list of the foods and drinks you can consume on a clear liquid diet:

• Light-colored Jell-O (no red or purple)
• Clear juice such as apple, cranberry or grape
• Kool-Aid
• Clear vegetable, chicken or beef broth
• Sports drinks, such as Gatorade
• Popsicles, but not fruit-containing Popsicles
• Pedialyte or other clear electrolyte replacement beverage
• Clear liquid supplements, such as Ensure Clear
• Black coffee
• Tea
• Lemonade (without pulp)
• Clear soda, such as Sprite, 7UP or ginger ale
• Seltzer water
• Fruit ice, such as a lemon ice

Clear Liquid Diet Menu

Although a clear liquid diet is lower in calories than a typical eating pattern, it does include some nourishment that can sustain you in the short term. Below is a typical day of eating on a clear liquid diet:

Breakfast: Coffee or tea; Jell-O; water or juice

Lunch: Clear broth; water, juice, ginger ale or other clear beverage

Snack: Fruit ice; water or juice

Dinner: Clear broth; water or juice; Popsicle

Who Should Follow a Clear Liquid Diet?

Pre- or post-surgery

"​​A clear liquid diet is typically used temporarily either pre- or post-surgery," says Andrews. The purpose of the clear liquid diet before surgery is to reduce bowel movement during surgery and hydrate the patient. After surgery, the clear liquid diet contributes to fluid intake, reduces nausea and minimizes gastric distress. "It is used as a progression towards solid food after surgery," says Ghida Arnaout, RD.

Before a colonoscopy

In addition to the colonoscopy prep drink that clears the bowels, a clear liquid diet is prescribed in the 24 hours leading up to the exam. This keeps the gastrointestinal tract free of any food, so the doctor can see clearly in the bowel region.

To treat diarrhea or vomiting

"It may also be used when a person is experiencing nausea, vomiting or diarrhea, to give the gastrointestinal tract a break from heavy meals," says Andrews. She notes that a clear liquid diet should not be followed for more than three to five days.

Risks of a Clear Liquid Diet

"Clear liquid diets are inadequate in calories, protein, vitamins and minerals, so they should be used only for very short periods and should be used only when medically necessary," says Arnaout. "Following this type of diet for an extended period of time could put a person at risk for malnutrition," notes Andrews.

Most of the foods on a clear liquid diet are high in carbohydrates and sugars, which can spike your blood sugar. "[Those with diabetes] who follow a clear liquid diet may be offered sugar-free alternatives," says Kolesa, but Andrews notes that the diet is so low in calories already that it's best not to use reduced or no-calorie foods.

Frequently Asked Questions

1. What can you eat on a clear liquid diet?

On a clear liquid diet, you can eat foods or liquids that are clear at room temperature. This includes water, most fruit juices without pulp, plain Jell-O, broth, tea, coffee, water, Popsicles, fruit ice and clear liquid nutritional supplements.

2. What's the difference between a clear liquid diet and a full liquid diet?

"Full liquids are of a thicker consistency (and [this] is a diet upgrade)" says Kolesa. "It provides more calories, protein and essential nutrients compared to clear liquids." Clear liquids are part of a full liquid diet, but you can also have strained or blended soups, milk or milk alternatives, dietary supplements, yogurt, ice cream, fruit puree, pudding, sherbet, strained oatmeal and cream of wheat.

3. Is applesauce OK for a clear liquid diet?

No, applesauce is not clear or liquid. It is considered a soft food, according to Arnaout.

4. What Jell-O is allowed on a clear liquid diet?

You can have a light-colored Jell-O, such as orange, yellow or green. Red or purple Jell-O may leave a residue in the bowel that resembles blood.

The Bottom Line

The clear liquid diet is a short-term prescription for pre- and post-surgery, colonoscopy prep or treatment for vomiting and diarrhea. Its main purpose is to give the bowels a rest so they can prepare for a procedure or recover from an illness. Although a clear liquid diet is very limited, it's generally doable for up to three days.