Liquid Diet


There definitely is no shortage of liquid diet plans out there today.  Considering that consumers spend over $1 billion a year on these types of diet plans, business continues to boom as consumers search for that quick weight loss fix.  Unfortunately, these programs may provide temporary weight loss, but the slew of accompanying health problems does not make them a healthy option for permanent weight loss.


You can lose weight by replacing meals with a convenient diet drink.


This approach to weight loss is based on the idea of meal replacement.  Shakes or drinks take the place of a balanced meal.  

Program Overview

This is a rather extreme way to restrict caloric intake.  Depending on the product, participants either partially or fully replace meals and snacks with some form of liquid substitute, typically in the form of a tea, juice, or shake.   Some plans suggest drinking the shakes/drinks for only one to two meals, then eating a sensible dinner.  Others require that the participant drink only shakes and eat no food for a specified period.  

Most liquid diet programs consist of anywhere from a two-week to three-month fasting period of liquid shakes, followed by some type of refueling stage (learning how to switch over to eating sensible meals), and then a maintenance stage (eating sensibly on your own without support).  Again, these programs can vary greatly so participants need to really dig into the specifics of each program, and would definitely benefit from discussing with a physician and dietician before undertaking.  

Liquid diets are sold over the counter, as well as under the medical supervision of a doctor. Each plan varies, placing its own unique “spin” on its product.  It’s probably therefore not surprising that some of these plans are more effective than others.

Variations of liquid diet programs include Ultra Slim Fast, Optifast, Medifast, HMR, Slender Now Thick Shake, and the Master Cleanse program.  

Plan Strengths

With most liquid diet plans, short-term weight loss will generally occur in most people.  Considering the severe restriction of calories and the body’s immediate ability to begin burning already-digested fat on tap, this outcome is pretty much a foregone conclusion. 

In cases of extreme obesity and under the supervision of a physician, liquid diets have proven successful for weight loss.  Generally, the more obese a participant is, the more weight is lost.  Researchers have also found that diet plans that include both food and liquids can assist overweight people in controlling the number of calories they eat, helping them to keep the weight off for several years.

Plan Weaknesses

The majority of liquid diets on the market are not suitable for long-term weight loss.  As mentioned, there is definitely not a problem in losing weight in the short term, but keeping it off is!  Liquid diets are not recommended as a long-term weight loss solution and for good reason.  Your body cannot survive and thrive on so few calories, and the lack of vital nutrients needed from eating a balanced diet.

The loss of vital nutrients has a significant impact on health.  Most liquid diets only provide 36 percent of recommended fiber and only 18 of 23 amino acids.  Furthermore, with only 400 to 800 calories allowed a day, participants can expect to experience more than a few serious side effects such as fatigue, dizziness, hair loss, muscle cramps, anemia, constipation, gallstones, and even heart damage.  Did I also mention the loss of lean body mass from a lack of protein?

Liquid diets have also been associated with various cardiac problems such as cardio arrhythmia, and individuals suffering from diabetes have had to struggle with dramatic fluctuating blood sugar levels resulting from the severe restriction of calories.  These diets are not for everyone, especially people suffering from pre-existing health problems, or women that are pregnant or nursing.  

Depending on the plan, it may or may not include a recommendation for exercise.  Ironically, though, given the severe restriction on calories, participants may find it difficult to maintain the level of energy needed to even exercise.


Liquid diets have always been a popular fad diet approach.  The idea of rapidly losing weight appeals to most individuals looking for that “quick fix”.  Unfortunately, these programs are generally not safe to undertake for any long period, unless under the watchful eye of a physician.  The immediate weight loss is definitely alluring, but when balanced with the potential health risks and the likelihood that any weight loss will reappear (along with probably a few extra pounds) in the long run, liquid diets really are not a safe or effective option for weight loss.

The information provided here is for educational or informational purposes only.  Dave DePew does not endorse any of the programs/services reviewed here. Before starting a new exercise regime or weight loss plan, talk with your doctor.

Additional Resources

Liquid Diets for Losing Weight,

Mayo:  Clear Liquid Diet, 

Liquid Diet,