Dangerous Side Effects of the Liquid Diet

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liquid diet
In recent years liquid only diets have become extremely popular.

Often advertised as ‘liquid detoxes’ or liquid cleanses’ they are all extremely similar, as they require the participant of the diet to consume only liquids for a set period of time.

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These liquid only diets can last anywhere from 3 days to 3 weeks.

They have been suggested to help promote rapid weight loss, and are often heavily endorsed by various celebrities who claim they have helped them lose some stubborn pounds in a very short amount of time.

Not to mention the extreme number of TV advertisements, promising a loss of ’10 pounds in 10 days’, etc. etc.

And their gaining popularity is understandable.

These types of diets genuinely appeal to human nature.

Who wouldn’t want to lose 10 pounds of fat in 10 days?

Without really working for it?

Sure you will be hungry, but you don’t have to cook.

Heck, you don’t even have to exercise!

Unfortunately, like most thing that sounds too good to be true, they probable are.

And despite the mass popularity of these liquid only diets, that does not mean they actually work as well as advertised.

In fact, they don’t work anywhere near as well as advertised.

Additionally, there are a number of potentially dangerous side effects associated with the liquid diet.

But first.

Do liquid diets actually work?

This answer is a little complicated.


But only for a little bit.

And definitely not to the degree advertised.

You see, using a liquid only diet approach, you are probably only going to be consuming ~700-800 calories per day.

Which is VERY LOW.

Depending on your size and weight, this could result in weight loss of anywhere from 2-6 pounds per week [1].


(There is always a ‘but’).

Due to the severe lack of protein in liquid only diets, majority of this weight lost is actually going to be coming from lost muscle tissue [2].

This is extremely bad, as it is muscle tissue that determines our Basal Metabolic Rate (the amount of energy we burn at rest).

So by losing weight in the short term, we are going to seriously limit our ability to lose weight in the long term [3].

Additionally, the weight lost is highly likely to be regained rapidly when normal eating habits are commenced.

So they do work, but not in the way that you think.

But, this drop in metabolism is not the only negative effect on health that liquid only diets can have.


These diets are typically very strict.

By strict, I mean they seriously limit the intake of a number of foods.

By excluding certain foods (in this case, often meats, grains, legumes, fruits and vegetables) we seriously limit the amount of nutrients we get through our diet.

This lack of nutrients can lead to malnutrition.

This malnutrition can then cause serious issues with immune system function, leading to disease and illness.

These effects are exacerbated the longer the liquid diet goes for, which in turn, also causes a longer recovery time to get our immune system functioning effectively again.

In conjunction with a significant lack of essential nutrients, these diets also have a serious lack of protein and fats.

By reducing these macronutrients, liquid diets are able to keep their calorie content low.

Unfortunately, both fats and proteins play a number of important roles within the human body.

They help build and repair damaged cells.

They are integral in the production of hormones and enzymes.

They promote the healthy structure of our organs.

They are used to create new blood cells, skin cells, nails and hair.

So, yeah.

They are both pretty important.

And almost eliminating them from the diet can lead to poor immune function and cellular degradation.

This can further lead to disease and illness, and even have implications on our cardiovascular systems.

Lack of energy and Irritable Bowel’s

With the combined effects of stress placed on the body as a result of malnutrition, and the poor protein intake, there a number of negative side effects associated with Liquid Diets.

It is extremely likely to experience head aches and hunger pains, while undergoing wild mood swings is also quite normal.

Due to the huge calorie deficit that the Juice Diet places the body in, it is very common to experience a lack of energy, in conjunction with sensations of fatigue and lethargy.

This can also be associated with hair loss, poor skin health, and poor nail health.

It is also important to consider that as the diet consist of only liquid, there is going to be considerable changes in our normal bowel function.

The exclusion of solids from the diet is going to result in A LOT more bathroom breaks than what you would normally need.

This can also cause the diarrhoea, which over time can even destroy some of the good bacteria found in the gut [4].

This can lead to even worse immune system function, further increasing the risk of developing illness and disease.

Damaged Metabolism

As mentioned previously, you are likely to experience significant muscle wastage during a liquid detox.

This muscle wastage will lead to a significant reduction in our metabolic rate [2].

This is going to have long term implications, by causing a significant reduction in our metabolism.

This will lower the amount of energy we use to complete the body’s essential functions each day, increasing our likelihood of regaining any of the weight we have lost.

In addition to this, as the body is taking in so little calories, it is going to go into what some refer to as ‘energy sparing’ mode.

This is when the body further slows its own metabolic rate as way to spare energy for really important metabolic processes.

These include the maintenance of our cell health, and the successful functioning of cardiovascular and respiratory systems, and the maintenance of our brain function.

This reduction in metabolism can last weeks after the completion of a very low calorie diet, such as that seen in liquid only diets.

This slowing of the metabolism can make it extremely difficult to lose weight in the future, rapidly speed up the process that weight regain can happen [3].

In Conclusion.

So, while liquid diets can cause short term weight loss, it comes at a pretty significant cost.

They can result in significant muscle wastage and long term metabolic damage, which can lead to rapid weight gain at the conclusion of the diet.

They can also lead to poor immune system functioning, irritable bowels, among a host of other negative side effects.

Liquid Diets.

Not worth the negatives associated.

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1. Tsai, A. G., & Wadden, T. A. (2006). The Evolution of Very‐Low‐Calorie Diets: An Update and Meta‐analysis.Obesity,14(8), 1283-1293. Viewed at: http://www.ncbi.nlm.nih.gov/pubmed/16988070
2. Bryner, R. W., Ullrich, I. H., Sauers, J., Donley, D., Hornsby, G., Kolar, M., & Yeater, R. (1999). Effects of resistance vs. aerobic training combined with an 800 calorie liquid diet on lean body mass and resting metabolic rate.Journal of the American College of Nutrition,18(2), 115-121. Viewed at: http://www.ncbi.nlm.nih.gov/pubmed/10204826
3. Saris, W. H. (2001). Very‐Low‐Calorie Diets and Sustained Weight Loss. Obesity Research,9(S11), 295S-301S. Viewed at: http://www.ncbi.nlm.nih.gov/pubmed/11707557
4. Slavin, J. L., Nelson, N. L., McNamara, E. A., & Cashmere, K. (1985). Bowel function of healthy men consuming liquid diets with and without dietary fiber.Journal of Parenteral and Enteral Nutrition,9(3), 317-321. Viewed at: http://www.ncbi.nlm.nih.gov/pubmed/2989571

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About the Author John Wright

John has been a fitness enthusiast for over 10 years, starting out while struggling with obesity as a teenager. Over the years he has advised numerous clients on how to transform their physiques and their lives. As a writer on Nutrition Inspector he aims to help others achieve real results by staying clear of the common hype and false claims in the supplement industry! You can contact him via the "About Us" page.

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