Detox ads often promote the removal of “toxins” but don’t specify which ones. Pesticides? Bisphenol A? Phthalates? You can’t set up a clinical study to test for “toxin removal” if you don’t name the toxin (and injecting toxins into subject’s bodies would hardly be ethical), so the idea remains neither proved nor disproved. It’s a dream scenario for deceptive marketing.

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“The concept of toxins is very vague,” Sherman said. “Most detox diets associate toxins with faeces, and [claim that] by encouraging bowel movements, you are eliminating these toxins. The idea that toxins stick to the intestinal wall creating toxic sludge and require washing away seems ingrained, and not only is there no evidence this happens, it’s simply not the way the system works. So yes, it is all marketing.”

I reached out to a dozen companies and practitioners who promote detox diets to ask which toxins are targeted, what proof they have that the toxins are removed, and if they have any clinical studies to back this up. None shared any proof of efficacy.

If there is little-to-no scientific evidence that detox diets work, why is it still a multibillion-dollar industry? It’s slick marketing that preys on our human desire for a quick fix, as well as years of ingrained, soul-harming diet culture, which values thinness, appearance and shape above health and well-being.

“Detoxes appeal to our natural desire for a fresh, clean start, and the desire to ‘undo’ perceived transgressions,” said Rachael Hartley, a dietitian and nutrition therapist in South Carolina, US. “Normal eating means sometimes eating in a less-than-balanced way, and there’s nothing you need to do to ‘undo’ that.”

“The idea that toxins stick to the intestinal wall creating toxic sludge and require washing away seems ingrained, and not only is there no evidence this happens, it’s simply not the way the system works. So yes, it is all marketing.”

Sherman explains that those in the Western world eat a lot of ultra-processed foods, which are devoid of fibre, the nutrient required for normal bowel movements. “The sequence of events is predictable,” Sherman said. “A poor diet leads to gastrointestinal discomfort and a sense of not feeling quite right, driving a desire to detox and ‘reboot the system.’”

The relief that comes with the laxative effect of detox diets may appear to be evidence that toxins were removed. But it’s simply the result of a long-overdue poop, a fact that is not nearly as appealing as “detoxification.”

While weight loss is possible with low-calorie liquid cleanses, it is also fleeting. “There is no credible science that detox diets do anything more than what all extreme caloric restricted diets also do,” Sherman said. “The weight loss results can be dramatic, but involve little actual fat loss; weight regain, therefore, is equally fast.”

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What about the popular claim that detoxes will help banish cravings? “That one always makes me laugh, because the one consistent thing I’ve heard from people who have done detoxes is that they’re craving solid food the entire time, and often binge after the detox is done,” Hartley said.

Some people say that regardless of the lack of clinically proven benefits, they feel energised and rejuvenated after a cleanse. So are detoxes safe to do occasionally?

“There’s a potential harm in taking poorly regulated supplements when you don’t know what’s in the bottle,” Ahuja added. “But with food products or juice, there’s unlikely to be harm.”

It’s unclear whether detoxing could affect nutrient absorption or negatively affect the healthy bacteria in the gut microbiome. Ahuja isn’t concerned about digestion and absorption if the detox is short-term (most detoxes are one to seven days). And though the microbiome can be affected by long-term diet changes, a short detox is unlikely to have much impact.

“Studies show that if you take colonoscopy prep, and you examine the stool a week later, the microbiome profile matches what was seen prior to the colonoscopy,” Ahuja said. “It really doesn’t move the needle, since it’s a short-term change, so a short-term detox diet likely won’t move the needle, either.”

Long-term detoxes (more than seven days) however, can lead to nutrient deficiencies, fatigue, electrolyte imbalances, low blood sugar and mood changes.

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Majumdar worries that beyond any potential physical harm, detox diets can cause mental or emotional harm. “Having unrealistic expectations about the intent and result can be disappointing,” she said. And Hartley said that liquid cleanses play into the restrict-binge cycle that often fuels disordered eating. Detoxing is a fad diet that’s part of the diet culture narrative that our bodies are unclean and require fixing.

So if you’re considering a cleanse, it makes more sense to establish a balanced eating plan to support your long-term health instead. And ignore the aggressive marketing that makes you feel like your body is filled with toxic sludge, because it’s not. The truth is, it’s normal to enjoy food. What shouldn’t be normal is an industry that exists to make us feel bad about ourselves and make money off false promises. This new year, instead of a detox, try to rid yourself of the influence of deceitful diet ads.

Dietitian Cara Rosenbloom is president of Words to Eat By and specialises in writing, nutrition education and recipe development. She is the co-author of Food to Grow On.

The Washington Post

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