Detox Diets and Cleanses: Health Boost or Recipe for Disaster?

4 Jan

Detox Diets and Cleanses: Health Boost or Recipe for Disaster?

By Tim Skwiat, MEd, CSCS, Pn2

There’s no doubt about it, the promises of detox diets and cleanses are alluring:

  • “Jump start your weight loss”…
  • ”Eliminate impurities”…
  • ”Drop 21 pounds in 10 days”…
  • ”Expel toxins”…
  • ”Revitalize and re-energize your body”…
  • ”Whisk away polluting nasties”…
  • ”Fast, easy weight loss”…
  • ”Purify the body”…
  • “Lose weight like the celebrities”…
  • ”Flush away toxins”

But do these plans work? Can they provide the health boosts they guarantee? Are they the perfect recipe that the proponents would like you to believe? Or, are they a recipe for disaster and self-sabotage, contributing to a vicious cycle and reinforcing poor eating habits and relationships with food?


One of the most challenging aspects of assessing the various detox diets and cleanses, which are typically characterized by severe food and energy (i.e., calorie) restriction, is that you’d be hard-pressed to find a specific scientific definition of either, which are typically interchangeable terms.

In the Detox Dossier, an investigation by the Voice of Young Science (VoYS) into 15 different products and special diets that are widely promoted as detoxes, a group of researchers found that no two companies use the same definition for “detox.”1,2 Not only that, the VoYS found that no program or company could name the supposed “toxins” targeted by its detox, and the proponents provided little—and in most cases, no—evidence to back up detox claims.

The VoYS concluded, “No one we contacted was able to provide any evidence for their claims, or give a comprehensive definition of what they meant by ‘detox.’ We concluded that ‘detox’ as used in product marketing is a myth. Many of the claims about how the body works were wrong and some were even dangerous.”

In other words, there’s virtually no agreement on what a detox diet is, and what’s more, not even the creators of these detox diets can verify what toxins they aid in eliminating nor provide any evidence that they actually “work.”

Along those lines, while the detox industry promotes “purification,” “cleansing,” and “elimination,” it’s incredibly important to point that the human body has evolved highly sophisticated mechanisms for eliminating toxins. The liver, kidneys, gastrointestinal system, skin, and lungs all play a role in the excretion of unwanted substances, without chemical intervention. For example, the liver and kidneys both serve as exceptionally effective “detox” organs, converting toxic chemicals into less harmful ones and promoting the excretion of unwanted chemicals.

In its Debunking Detox Leaflet, the VoYS echoes the above: “Your body is capable of removing most potentially harmful chemicals you will encounter in your daily life. The human body has evolved to get rid of unnecessary substances through your liver, kidneys, and colon. It isn’t possible to improve their function without medical assistance.”3

The VoYS is not the only group of health professionals that’s out to set the record straight on the topic of detox diets. The Dietitians Association of Australia have also heavily criticized several popular detoxes, which can result in the loss of healthy gut bacteria and electrolytes.4

Dietitian Melanie McGrice says, “The problem with fad diets is that they’re all about restrictive eating patterns that you can’t stick to over the long haul and may even undermine your health. What you lose on these detox diets is usually fluid, healthy gut bacteria, electrolytes—all the things to keep your body healthy—rather than fat. And you don’t need to go on a severe detox because your body has an inbuilt detox system: the lungs, liver, and kidneys working every minute of the day.”

In a study published in the Journal of Human Nutrition and Dietetics, researchers Professor Hosen Kiat, Head of Cardiology at Macquarie University Hospital and the Australian School of Advanced Medicine, and Dr. Alice Klein from the Cardiac Health Institute conducted a thorough review of the currently available research to assess whether there was any clinical evidence to support the use of detox diets for weight management or toxin elimination. They concluded, “Although the detox industry is booming, there is very little clinical evidence to support the use of these diets. To the best of our knowledge, no randomized controlled trials have been conducted to assess the effectiveness of commercial detox diets in humans.”5

The researchers also identified a number of concerns and potential health risks. For instance, detox diets typically involve severe calorie restriction and nutritional inadequacy. Professor Kiat said, “In assessing one detox diet we found that, based on the average person’s minimum daily energy requirement, it does not meet daily protein requirements for anyone who weighs more than 23 kg [i.e., 50 pounds].”

The take-home point is that there’s no medical evidence indicating that specialized detoxification programs are needed to rid the body of toxins. With that being said, just because the body is equipped with the machinery it needs to “cleanse” and “detoxify” itself and to do so remarkably well, that does not mean that exposure to pollutants, pesticides, food additives, etc., is not a big deal. That point should not be lost; however, it is to say that these approaches do not appear to be effective solutions or quick fixes in that regard.


As mentioned above, another reason that folks turn to these drastic approaches is to promote weight management. As Professor Kiat and Dr. Klein’s extensive review demonstrated, there’s very little clinical evidence to support this.5 But there’s much more to the story to consider.

While these popular diets help control energy balance, detox diets typically involve severe energy restriction and nutritional inadequacy, which can lead to protein and vitamin deficiencies, electrolyte imbalances, lactic acidosis, as well as decrements in performance (mental and physical), hormonal imbalances, hair loss, and much, much worse. (Yes, even death.)

Even more, this type of approach lends itself to weight cycling, which may be more commonly recognized as “yo-yo dieting.” Numerous studies have provided evidence that weight cycling increases one’s risk of insulin resistance, type 2 diabetes, and cardiovascular disease.6–8 While very-low-calorie diets (VLCD) like these may lead to significant short-term weight loss, VLCDs do not lead to greater long-term weight loss compared to more moderate reduced-calorie diets.9

For those folks who find themselves resorting to this vicious cycle, it’s important to mention that long-term calorie restriction has been shown to lead to significant reductions in metabolic rate that rival that of life-threatening malnutrition and starvation.10 In other words, chronic dieters—who are often the type to gravitate toward extreme approaches such as detox diets and cleanses—are at risk of a drastically reduced metabolic rate that significantly exceeds what would be predicted by age, sex, and body composition.

It’s also noteworthy to point out that a significant percentage of the short-term weight loss associated with VLCDs is fat-free mass (e.g., muscle mass, glycogen, body water), not body fat. This disproportionate loss in fat-free mass (FFM) is one contributor to a decreased metabolic rate, as FFM comprises the metabolically active tissues of the body, and may also predispose one to weight regain.11,12

When talking about extreme energy restriction, such as the case with the majority of these programs, it’s also important to discuss metabolic adaptation (i.e., adaptive thermogenesis), which refers to the decrease in energy expenditure beyond what can be explained by a loss in FFM.13 In the face of dangerously low energy supplies and stores, this form of energy conservation, which is characterized by reductions in key hormones (e.g., leptin, thyroid hormone, insulin, catecholamines), is a biologically meaningful survival mechanism.10,14,15

However, most people who engage in these restrictive diets generally aren’t trying to get themselves ready for some sort of apocalypse involving a food shortage. Rather, they tend to be using them as a vehicle to optimize body composition, health, and/or performance, and considering that studies show that metabolic adaptation is proportionate to the degree of energy imbalance, this shouldn’t be viewed favorably. Not only are intense energy-restrictive diets tough to maintain, they trigger the body to suppress its resting metabolic rate (RMR) by as much as 20%.9,16

Another fundamental concept to consider is that a crucial component of effective weight management plans and an overall healthy lifestyle is regular physical activity. Rarely do detox diets or cleanses promote exercise, and considering that many of these programs severely restrict caloric intake, not enough calories are being consumed to fuel physical activity. This is important for a number of reasons, one of which is that adding exercise to a weight loss program tends to help spare FFM.17–19

A key objective during weight loss is to reduce body fat while minimizing loss of FFM to promote optimal overall health, metabolic function, cardiovascular health, and physical functioning. This is why an emphasis should be placed on fat loss as opposed to weight loss.


Some might consider highly-restrictive plans like these (i.e., detox diets, cleanses) as “quick fixes,” but truth be told, they’re not really fixing anything. In fact, as outlined above, they’re quite possibly making things worse. With reductions in RMR (via reduced FFM and adaptive thermogenesis), one is putting him/herself at a greater predisposition for weight regain.

This is particularly true because these plans do little to teach folks how to eat or help them overcome individual limiting factors (e.g., creating a healthy food environment, preparing healthy food choices, cultivating a healthy relationship with food). Not only that, programs like these that heavily restrict both calories and specific foods and food groups make folks more prone to oversconsumption of high-calorie, highly palatable foods via metabolic adaptation and through the activation of hedonic pathways.20 Severe restriction increases appetite (via “hunger hormones”), as well as the activity of hunger and food reward centers. That’s right, “junk food” becomes even tastier, and an even greater amount of it is craved by the body to satisfy its “needs.”

It’s indeed plausible that one could feel better during a detox diet or cleanse. With that in mind, it’s important to point out where some of these plans may go “right.” This most likely is a result of dietary displacement, which simply means replacing less-healthy options with healthier ones. On one hand, if the detox increases one’s consumption of vegetables and fruits, then s/he is going to be bringing in copious amounts of micronutrients, fiber, and phytonutrients, all of which can have a beneficial effect on healthy, body composition, metabolism, feelings of wellbeing, and energy levels.

Conversely, dietary displacement also takes into account you are not eating when following one of these detox diets. If one’s diet resembles anything like that of the typical Western diet, then these types of programs will substantially reduce the overconsumption of energy and processed foods, and that means reductions in calorie intake, sugar, refined grains, and added fats and oils (i.e., industrial vegetable oils).

Research shows that the typical Western diet leads to increased incidence of obesity, metabolic syndrome, oxidative stress, chronic inflammation, cognitive dysfunction, and various chronic diseases and forms of cancer.21–24 Simply by process of elimination, one may look and feel better. That’s not to say that a detox diet is a “good” plan; rather, this highlights how poor typical eating behaviors truly are.


Rather than resorting to an extremist approach that does nothing to promote good nutrition behaviors, teach you how to eat, encourage a healthy relationship with food, or promote a healthy food environment, focus on making changes that support long-term healthy habits. Not only do you not have to suffer and deprive yourself through dramatic restriction, you can enjoy great-tasting whole foods and fully support your health and body composition goals.

In the grand scheme of things, your health, fitness, performance, and body composition are contingent on your entire body of “nutrition work”—not an individual food or special diet. In other words, there’s no “magic bullet.” Instead of viewing foods in isolation as “good” or “bad” or thinking you need to “go on a diet,” think about weight management and “deep health” as the product of practicing healthy eating habits, creating a positive food environment, and choosing high-quality, nutritious foods in appropriate amounts relative to your goals and activity levels regularly and consistently over time. Good nutrition takes practice, and just like getting better and mastering anything in life, it’s about progress—not perfection.

Start where you are and make small changes that you are ready, willing, and able to take on; focus on mastering those new behaviors, one step at a time.

Helpful next steps:



  1. Voice of Young Scientists. THE DETOX DOSSIER. Sense About Science; 2009.
  2. Sense about Science. Debunking detox. Sense Sci. January 2009.
  3. Voice of Young Scientists. Debunking detox leaflet. January 2009.
  4. NewsMail. Dietitians reveal the three worst diets for your health. January 2014.
  5. Klein AV, Kiat H. Detox diets for toxin elimination and weight management: a critical review of the evidence. J Hum Nutr Diet Off J Br Diet Assoc. 2015;28(6):675-686. doi:10.1111/jhn.12286.
  6. Li Z, Hong K, Wong E, Maxwell M, Heber D. Weight cycling in a very low-calorie diet programme has no effect on weight loss velocity, blood pressure and serum lipid profile. Diabetes Obes Metab. 2007;9(3):379-385. doi:10.1111/j.1463-1326.2006.00621.x.
  7. Waring ME, Eaton CB, Lasater TM, Lapane KL. Incident Diabetes in Relation to Weight Patterns During Middle Age. Am J Epidemiol. 2010;171(5):550-556. doi:10.1093/aje/kwp433.
  8. Olson MB, Kelsey SF, Bittner V, et al. Weight cycling and high-density lipoprotein cholesterol in women: evidence of an adverse effect. J Am Coll Cardiol. 2000;36(5):1565-1571. doi:10.1016/S0735-1097(00)00901-3.
  9. Tsai AG, Wadden TA. The evolution of very-low-calorie diets: an update and meta-analysis. Obes Silver Spring Md. 2006;14(8):1283-1293. doi:10.1038/oby.2006.146.
  10. Weyer C, Walford RL, Harper IT, et al. Energy metabolism after 2 y of energy restriction: the biosphere 2 experiment. Am J Clin Nutr. 2000;72(4):946-953.
  11. Müller MJ, Bosy-Westphal A, Kutzner D, Heller M. Metabolically active components of fat-free mass and resting energy expenditure in humans: recent lessons from imaging technologies. Obes Rev Off J Int Assoc Study Obes. 2002;3(2):113-122.
  12. Faria SL, Kelly E, Faria OP. Energy expenditure and weight regain in patients submitted to Roux-en-Y gastric bypass. Obes Surg. 2009;19(7):856-859. doi:10.1007/s11695-009-9842-6.
  13. Camps SGJA, Verhoef SPM, Westerterp KR. Weight loss, weight maintenance, and adaptive thermogenesis. Am J Clin Nutr. 2013;97(5):990-994. doi:10.3945/ajcn.112.050310.
  14. Heilbronn LK, de Jonge L, Frisard MI, et al. Effect of 6-Month Calorie Restriction on Biomarkers of Longevity, Metabolic Adaptation, and Oxidative Stress in Overweight Individuals: A Randomized Controlled Trial. JAMA. 2006;295(13):1539. doi:10.1001/jama.295.13.1539.
  15. Rosenbaum M, Leibel RL. 20 YEARS OF LEPTIN: Role of leptin in energy homeostasis in humans. J Endocrinol. 2014;223(1):T83-T96. doi:10.1530/JOE-14-0358.
  16. Knuth ND, Johannsen DL, Tamboli RA, et al. Metabolic adaptation following massive weight loss is related to the degree of energy imbalance and changes in circulating leptin. Obes Silver Spring Md. 2014;22(12):2563-2569. doi:10.1002/oby.20900.
  17. Garrow JS. Exercise in the treatment of obesity: a marginal contribution. Int J Obes Relat Metab Disord J Int Assoc Study Obes. 1995;19 Suppl 4:S126-S129.
  18. Redman LM, Heilbronn LK, Martin CK, et al. Effect of calorie restriction with or without exercise on body composition and fat distribution. J Clin Endocrinol Metab. 2007;92(3):865-872. doi:10.1210/jc.2006-2184.
  19. Stiegler P, Cunliffe A. The role of diet and exercise for the maintenance of fat-free mass and resting metabolic rate during weight loss. Sports Med Auckl NZ. 2006;36(3):239-262.
  20. Greenway FL. Physiological adaptations to weight loss and factors favouring weight regain. Int J Obes. 2015;39(8):1188-1196. doi:10.1038/ijo.2015.59.
  21. Heinonen I, Rinne P, Ruohonen ST, Ruohonen S, Ahotupa M, Savontaus E. The effects of equal caloric high fat and western diet on metabolic syndrome, oxidative stress and vascular endothelial function in mice. Acta Physiol Oxf Engl. 2014;211(3):515-527. doi:10.1111/apha.12253.
  22. Lutsey PL, Steffen LM, Stevens J. Dietary Intake and the Development of the Metabolic Syndrome: The Atherosclerosis Risk in Communities Study. Circulation. 2008;117(6):754-761. doi:10.1161/CIRCULATIONAHA.107.716159.
  23. Cordain L, Eaton SB, Sebastian A, et al. Origins and evolution of the Western diet: health implications for the 21st century. Am J Clin Nutr. 2005;81(2):341-354.
  24. Kanoski SE, Davidson TL. Western diet consumption and cognitive impairment: Links to hippocampal dysfunction and obesity. Physiol Behav. 2011;103(1):59-68. doi:10.1016/j.physbeh.2010.12.003.

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