There are plenty of restrictive diets out there, but one of the most limiting is the clear liquid diet. Unlike dietary programs for weight loss or lowering cholesterol, a clear liquid diet is used for a few specific purposes and usually for a very short period. 

This highly restrictive diet is typically prescribed by a doctor before medical tests are performed or after certain kinds of surgeries. Since it is difficult to maintain the amount of nutrition your body needs without solid food, you should never go on a clear liquid diet unless directed to by your doctor. Even then, you should typically only remain on this type of diet for a few days.

What is a Clear Liquid Diet?

As the name implies, a clear liquid diet is one where you only consume liquids you can see through. This means water, clear soups, certain kinds of sports drinks, and other clear beverages, but that is all. No solid foods are allowed, and even juices that contain pulp, such as orange juice or lemonade, need to be avoided. 

Knowing whether a liquid is allowed is mostly a common sense decision; if you can see through it, you are probably safe to consume it. There are a few tips that can help you know if a specific liquid is off-limits or not. One clarification often given is that a liquid must be clear at room temperature, as there are some foods that are only clear when heated. These should be avoided, as they typically contain fats and do not meet the requirements of the diet. 

Why do Doctors Prescribe Clear Liquid Diets?

The goal of a diet made of only clear liquids is to allow your digestive tract to rest and clean itself out. This can be necessary for performing certain types of tests like colonoscopies, or it can be needed after surgery to your intestinal tract. It is also possible you might have to temporarily go on a clear liquid diet to alleviate or eliminate symptoms of medical conditions such as diarrhea, diverticulitis, or Crohn's disease. In all these cases, the goals are to allow the intestinal tract to rest and to clear out any undigested food residue that may remain in your gut. 

Doctors may prescribe clear liquid diets ahead of colonoscopies or other procedures. Allowing your intestines to clear out completely helps your doctor accurately identify and diagnose any potential digestive conditions you may have. If this is the reason you have been placed on a clear liquid diet, you will need to be careful to avoid drinking any liquids with red dye, as these can sometimes affect test results. 

What Can I Eat on a Clear Liquid Diet? 

It may seem like culinary torture at first, but chances are your diet will involve more than just plain water. Often, you will still be able to start your day with a comforting cup of coffee. Adding some variety will not only help keep the diet from feeling monotonous, but will also give you the best access to as wide a range of dietary sugars, fats, vitamins, and minerals as possible.

It may feel like your diet is quite restricted when you are told to only eat clear liquids, but as the sample menu below suggests, there are actually quite a few options. One thing that is important to practice, especially if you are going to be on a clear liquid diet for several days, is to include as wide a variety as possible of different liquids. This will span the range from fruit juices such as apple juice and grape juice to clear broth soups and consommé made with bouillon or stock. A short list of liquids encouraged for most liquid diets includes:

  • water
  • ice chips
  • coffee without dairy products like cream or milk
  • tea (sweetened, but without milk or cream)
  • clear nutritional drinks (Ensure Clear, Enlive)
  • sports drinks (Gatorade, Powerade, Vitamin Water)
  • soft drinks such as Sprite, Pepsi, and Coca-Cola
  • ginger ale
  • clear soups or consommé 
  • clear (fat-free) broth
  • juices without pulp (apple and white cranberry)
  • strained tomato or vegetable juice
  • lemonade, grapefruit, and orange juice (allowed only without pulp or bits of fruit)

There are some other foods that people may not typically think of as liquids, but are still typically allowed on a clear liquid diet. These include some of the following options:

  • hard candies (lemon drops or peppermint rounds)
  • honey
  • plain gelatin (Jell-O)
  • popsicles without fruit pulp or fruit pieces inside

Things to Know Before Starting a Clear Liquid Diet

No matter how hard you try, a clear liquid diet is not going to give you the mix of vitamins, minerals, and fats needed to keep your body healthy in the long term. If your doctor is trying to manage certain digestive problems, or you have just had surgery, a liquid diet may be the only option for a short period. 

At Cary Gastroenterology Associates, our doctors and dietitians are very familiar with the clear liquid diet. We often prescribe these diets to patients before colonoscopies and other procedures, after surgeries to the digestive tract, and to help treat many other digestive conditions. We can help you know what to expect, how to prepare for going on a clear liquid diet, and how to make sure you avoid common mistakes that can affect test results or cause complications.  We are ready and waiting to help you maintain your digestive health here at Cary Gastroenterology, even during the ongoing challenges of COVID-19. We have now resumed in-office visits for those patients whose condition requires in-person visits. We are also offering telemedicine visits for those patients who may be concerned about their potential exposure to the coronavirus. Whether you choose telemedicine or an in-office visit, your request for an appointment is the first step to putting you in touch with our talented and dedicated team of physicians.