Every January, and increasingly every month, the same products reappear: juice cleanses, detox teas, elimination protocols, foot pads that claim to draw toxins out through your soles.
They share a common structure. A vague claim that your body has accumulated toxins, a restrictive programme lasting three to fourteen days, and a promise of energy, clarity and weight loss at the end.
The interesting question is not whether they work. It is what they are actually doing, because people do frequently feel different afterwards — and the reasons have almost nothing to do with detoxification.
The missing noun
Start with the simplest test, which almost no detox product survives: name the toxin.
Detox marketing is remarkably consistent in avoiding this. Products refer to "toxins", "impurities", "build-up" and "sludge" without ever specifying a compound that could be measured before and after.
This is not an accident of casual writing. Naming a substance would invite measurement, and measurement would settle the question. A 2009 investigation by a group of scientists contacted the manufacturers of dozens of products marketed as detoxifying and asked them to define what they removed and provide evidence. Not one could give a coherent answer.
Where real toxins are involved — heavy metal poisoning, drug overdose, certain occupational exposures — medicine has specific treatments called chelation therapy, administered under supervision. They are targeted, monitored, and have nothing in common with a bottle of green juice.
What the body already does
You already have a detoxification system, and it is considerably more sophisticated than anything sold in a bottle.
The liver handles the bulk of it, in two phases. Phase one uses a family of enzymes to chemically modify compounds. Phase two attaches molecules that make the result water-soluble, so it can be excreted. This system handles alcohol, medications, environmental compounds and the by-products of normal metabolism, continuously and without instruction.
The kidneys filter roughly 180 litres of blood-derived fluid per day, reabsorbing what is needed and excreting the rest.
The lungs remove volatile compounds, including carbon dioxide. The gut eliminates what was never absorbed. Skin plays a minor role, and sweat is overwhelmingly water and salt — it is not a meaningful excretion route for toxins, which is worth knowing before paying for a sauna programme sold on that basis.
None of these systems needs activating, and no food switches them on. What they need is adequate hydration, sufficient protein for the enzymes and conjugation molecules involved, and the absence of things that damage them — chiefly excess alcohol.
Why people feel different anyway
This is the part that deserves an honest answer rather than dismissal. People often do report feeling better, and there are real mechanisms behind it.
They stopped drinking alcohol. Most detox programmes exclude it. For anyone drinking regularly, a week off produces better sleep, better mood and less inflammation. This effect is real and is entirely attributable to the alcohol, not the juice.
They stopped eating ultra-processed food. Cutting out high-sugar, high-refined-carbohydrate foods for a week produces genuine changes in energy stability, whatever replaces them.
They are eating more vegetables and fruit. More fibre, more potassium, more micronutrients. Good, and available without a programme.
They are more hydrated. Mild dehydration causes fatigue and headache in a large number of people who never connect the two.
They lost weight quickly. Severe calorie restriction depletes glycogen, and each gram of stored glycogen holds several grams of water. Several kilograms can disappear in days, almost all of it water, and almost all of it returns.
They expected to feel better. Placebo effects are strong for subjective outcomes like energy and clarity, and a programme involving effort, expense and ritual maximises them.
Notice that every one of these is a consequence of ordinary dietary change. None requires the detox framing, and all of them can be kept permanently rather than for a week.
Where it goes wrong
Juice cleanses in particular have specific problems.
Juicing removes fibre, which is the most valuable component of fruit for most people. What remains is largely sugar and water with vitamins. A day of juice can contain a surprisingly large amount of sugar in a rapidly absorbed form.
Protein is essentially absent. Extended very low protein intake causes loss of lean tissue — muscle — which is precisely what you do not want to lose, and which lowers resting metabolic rate.
Very low calorie intake for more than a couple of days produces fatigue, irritability, poor concentration and headaches, which are frequently reframed by the seller as "toxins leaving the body." They are the symptoms of not eating.
Detox teas frequently contain senna or other stimulant laxatives. These do not remove toxins; they accelerate bowel transit, cause fluid and electrolyte loss, and with regular use can lead to dependence. The weight lost is stool and water.
There are genuine risks in specific groups. Excessive water intake without electrolytes can cause dangerous sodium dilution. People with kidney disease can be harmed by high-oxalate juice regimes. Diabetics on medication risk hypoglycaemia. Anyone on prescription medication should note that grapefruit and some other juices interact meaningfully with liver enzymes and can alter drug levels.
And for some people, the cleanse-then-binge cycle is a route into disordered eating, dressed up as wellness.
The parts that are not nonsense
A few elements of these programmes have merit, once detached from the marketing.
A structured break from alcohol has well-documented benefits.
Elimination diets are a legitimate clinical tool when supervised, used to identify food intolerances by removing suspected foods and reintroducing them systematically. This is a diagnostic process, not a cleanse.
Time-restricted eating and intermittent fasting have their own evidence base, mixed but real, and are entirely separate from detoxification claims.
Deliberately eating more vegetables for a period, and noticing how it feels, is a reasonable way to change habits — provided the change outlasts the week.
A better approach
If the goal is to feel better, the boring version works and keeps working:
- Drink less alcohol, or none
- Eat enough fibre — most people fall well short
- Drink enough water
- Get enough protein, particularly if you are eating less overall
- Sleep, which is when a great deal of metabolic clearance actually happens
- Move regularly
- Do not smoke
None of this can be sold in a seven-day box, which is precisely why it is not.
The short version
Your liver and kidneys detoxify you continuously and do not require assistance from juice. Programmes that promise otherwise cannot name what they remove. The improvements people feel are real but come from cutting alcohol and processed food, hydrating and eating vegetables — all of which you can do permanently, for less money, without the fasting.
Be the first to share a thought.