Your body already detoxes itself, and a few everyday habits help it work

Key takeaways

• Your kidneys filter about 150 quarts of blood a day, and a review cited by NIH’s integrative-health center found no compelling evidence that detox diets remove toxins.
• In a U.S. network that studies serious liver injuries, the share caused by herbs and supplements rose from 7% to 20% between 2004 and 2013.
• If you aren’t short on a nutrient, routine vitamin and mineral pills probably do little to prevent infections, according to NIH’s Office of Dietary Supplements.
• In a 1995 study, small skin wounds took about nine days longer to heal in women caring for a relative with dementia than in similar people without that strain.
• A “supports” claim on a supplement needs no FDA review before sale; the company only has to notify FDA within 30 days and say it has evidence.

Every day, without a single cleanse, your kidneys filter about 150 quarts of blood. That works out to roughly half a cup a minute³.

From all that blood, they make only 1 to 2 quarts of urine. They pull out wastes, extra fluid and acid, then return almost everything else to your bloodstream³.

Your liver, the largest organ inside your body, helps digest food, stores energy and removes poisons⁴. Your immune system remembers germs it has met before⁷. Your skin closes a cut in a set order of steps¹⁰.

Natural health has always honored this. The belief that the body can heal itself, given the right conditions, sits at the heart of the movement. It is also the promise on thousands of labels: “supports natural detox,” “supports immune health,” “supports healthy liver function.”

Science backs the first half of that belief more than the second. The body’s repair systems are real and remarkable. What helps them most is mostly free, while many products sold to support them have little evidence, and a few have caused harm.

Science gave the body’s self-healing a name: homeostasis

The idea that nature heals is ancient. Naturopathy, which the National Center for Complementary and Integrative Health (NCCIH) says grew from traditional practices popular in 19th-century Europe, treats symptoms as the body’s signals and aims at root causes¹.

Laboratory science reached a related idea by a different road. The physiologist Claude Bernard, whose 1865 book pushed medicine toward controlled experiments, described the body’s “inner environment.” He meant the stable conditions inside us that hold steady while the outside world changes².

In 1926, the physiologist Walter Cannon built on Bernard’s work and coined the word “homeostasis”². He picked a Greek root meaning “similar,” not “same.” Balance in the body is always being adjusted, never frozen².

That detail matters for anyone who wants to support the body. Your systems are not waiting for a product to switch them on. They are running all the time, correcting course every minute.

Supporting them mostly means two things: give them what they need, and stop piling on what overloads them. The rest of this article tests that idea system by system.

Your liver and kidneys already run the detox

Each kidney holds about a million tiny filters called nephrons³. Together they balance your body’s water, salt, potassium, calcium and phosphorus. They also make hormones that help control blood pressure, build red blood cells and keep bones strong³.

The liver handles the chemical side, breaking down and clearing poisons along with its work on digestion and energy storage⁴.

So what about detox diets and cleanses? NCCIH’s fact sheet, updated in 2025, says there are only a small number of human studies. Most were low quality, with few participants, design flaws or no peer review⁵.

A 2015 review found no compelling research that detox diets help with weight control or remove toxins. A 2017 review found that juice and detox diets cause quick weight loss from eating so little, and the weight tends to come back⁵. No one has studied their long-term effects⁵.

Cleanses can also cause harm. NCCIH lists these risks⁵:

• Colon cleansing can cause serious side effects, especially for people with bowel disease, past colon surgery, kidney disease or heart disease.
• Juices made from high-oxalate foods, such as leafy greens and beets, may be risky for people prone to kidney stones.
• Unpasteurized juice can make children, older adults and people with weak immune systems seriously ill.
• Laxatives can cause diarrhea and dehydration.
• Drinking large amounts of fluid while eating nothing for days can throw off the body’s salt balance dangerously.

Federal regulators have also stepped in. The Food and Drug Administration (FDA) and the Federal Trade Commission (FTC) have acted against detox sellers for hidden harmful ingredients, false claims to treat serious disease and unapproved colon-cleansing devices⁵.

Real poisonings are different. Toxic metal exposure, for example, gets medical treatment, not a juice fast⁵. If you think someone has swallowed something toxic, call Poison Control at 1-800-222-1222.

Some “support” products end up hurting the liver

The liver clears what you swallow, including pills and herbs. Sometimes that work injures it.

The U.S. Drug-Induced Liver Injury Network tracks serious cases at eight referral centers. In a 2014 report in the journal Hepatology, researchers reviewed 839 people whose liver injuries were judged to come from a drug or supplement between 2004 and 2013⁶.

Herbs and dietary supplements caused 130 of those cases, or 15.5%. Over the study years, their share climbed from 7% to 20%⁶.

Bodybuilding products mostly hurt young men, and none of those cases ended in death or a transplant⁶. Other supplements mostly injured middle-aged women, and those cases were more severe: 13% ended in death or a liver transplant, compared with 3% of injuries from medicines⁶.

That is a sobering fact for anyone who buys a product to “support” the liver or “detox” the body. A pill or herb can injure the very organ that does the cleaning.

These are cases sent to specialty centers, so they show a trend in serious injuries, not how often the average user gets hurt. Still, the direction is clear.

Alcohol remains the best-known liver threat. MedlinePlus, from the National Library of Medicine, lists too much alcohol, along with drugs and poisons, as causes of liver disease⁴. It also links readers to LiverTox, a government resource on drug-induced liver injury⁴.

Your immune system gets trained, not “boosted”

NIH’s Office of Dietary Supplements (ODS) describes two branches of immunity⁷. The innate branch is your first line of defense: physical barriers, such as skin, plus white blood cells that attack any invader⁷.

The adaptive branch is slower and more precise. Its B cells make antibodies and its T cells target specific germs, and it can take days or weeks to respond the first time⁷. Then it remembers. Vaccines work by training this branch so it is ready for a future exposure⁷.

Nutrition matters, but in a specific way. True shortages of vitamins A, C, D and E, selenium or zinc can weaken immunity⁷. Without a shortage, ODS says routine vitamin and mineral pills probably do little to prevent or treat infections⁷.

Here is what ODS reports for popular immune supplements⁷:

• Vitamin c: Taken daily, it didn’t lower the general population’s risk of colds in a 2013 review, but a 2021 analysis found colds lasted about 9% less time. Starting it after symptoms began showed no consistent benefit.
• Vitamin d: A 2017 analysis found 12% fewer respiratory infections with daily or weekly doses, but two 2022 trials found no reduction.
• Zinc: Lozenges or syrups shortened colds by about two days in a 2021 analysis, but didn’t prevent them. Long-term high doses can lower copper and weaken immunity.
• Echinacea: A 2014 Cochrane review suggested a weak 10% to 20% drop in cold risk and no help treating a cold.

More is not always better. In one analysis, higher-than-standard vitamin A doses raised respiratory infections by 66% in children whose nutrition was already normal⁷.

Sleep is repair time, though the brain-cleaning story is unsettled

NIH’s sleep experts say most adults need at least seven hours a night⁸. Regularly falling short raises the risk of heart disease, stroke, obesity and dementia⁸.

Kenneth Wright Jr., a sleep researcher at the University of Colorado, has said the immune system uses sleep as repair time, and some of the body’s repair work happens mostly during sleep⁸. In his team’s studies, people who were kept short on sleep gained weight and handled blood sugar worse. Sleeping in on the weekend did not undo it⁸.

Then there is the brain. In 2013, Maiken Nedergaard’s team at the University of Rochester reported on the brain’s drainage network, often called the glymphatic system, in mice⁸. During sleep, it cleared some proteins linked to Alzheimer’s disease about twice as fast as during waking hours⁸.

That finding spread quickly as “sleep washes your brain.” In 2024, scientists at Imperial College London tracked a glowing dye through the brains of mice, a more direct measure than earlier studies had used⁹. In sleeping mice, the dye cleared about 30% more slowly than in awake ones, and half as fast under anesthesia⁹.

Both studies were in mice, and the 2024 team said its results may not hold for every molecule. It also doesn’t yet know why sleep slowed clearance⁹. Its co-leader, Bill Wisden, stressed that no one disputes that sleep matters⁹.

What is unsettled is one mechanism, not the value of a good night’s sleep. Be wary of any product that promises to “detox your brain.”

Wounds heal in stages, and stress slows them

A health guide from Columbia University walks through how a cut heals¹⁰. First, a clot plugs the bleeding. Next comes inflammation, when extra blood flow carries infection-fighting cells to the wound.

About five days in, skin cells crowd into the injury and start rebuilding. In the final stage, the scar slowly thins and flattens¹⁰.

Things that can slow the process include smoking, high blood sugar from type 2 diabetes, too little protein, older age, poor sleep, chronic stress and alcohol¹⁰.

Stress has some of the most striking data. In a 1995 study in The Lancet, Kiecolt-Glaser and colleagues made a small, standard 3.5-millimeter skin wound on 13 women caring for a relative with dementia. They did the same for 13 people matched for age and family income¹¹.

The caregivers’ wounds took an average of 48.7 days to heal, compared with 39.3 days for the comparison group. That is about nine days longer¹¹. Their immune cells also made less of a key healing signal¹¹.

A later review by the same research group found that stress, from long-term caregiving to short-term exam stress, slows healing in people and animals¹². It also found that exercise and social support can help prevent those stress-related delays¹².

What “supports” means on a supplement label

A supplement may say it supports a body structure or function. These are called structure/function claims. Federal rules let a label describe how a nutrient or ingredient affects normal body structure or function, as long as it doesn’t claim to diagnose, treat, cure or prevent a disease¹³.

No FDA review is required before the claim goes on sale. The company must notify FDA within 30 days after it starts selling the product and certify that it has evidence the claim is truthful and not misleading¹³. FDA doesn’t check that evidence in advance.

The label must also carry this required statement¹³: “This statement has not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.”

One detail of that rule is in flux. In a December 11, 2025, letter, FDA told industry it would not enforce the requirement that the statement appear on every label panel carrying a claim, and that it was likely to propose a rule removing it¹⁴. The statement itself must still appear on the label, linked to each claim¹⁴. As of mid-October 2026, the federal regulation itself had not been changed¹³.

Our article on supports-versus-cures claims covers the details.

Put plainly, “supports immune health” tells you an ingredient plays some role in normal immunity. It does not tell you the product does anything for a healthy person who isn’t deficient.

The label says	What it can mean	What to ask
“Supports natural detox”	An ingredient plays some part in normal liver or kidney work	Was it tested in healthy people? Did they clear anything faster?
“Supports immune health”	A nutrient is involved in immunity	Am I short on this nutrient?
“Supports healthy liver function”	An ingredient touches normal liver processes	Has this ingredient been linked to liver injury?
“Promotes restful sleep”	An ingredient affects normal sleep processes	What are my sleep habits missing first?

What supports each system

This table rates common practices and products using our four-level evidence scale.

System	Practice or product	What research shows	Evidence rating
Liver and kidneys	Detox diets and juice cleanses	Few, low-quality studies; lost weight returns5	Not enough evidence
Colon	Colon cleansing	Limited evidence and possible serious side effects5	Evidence says no, or unsafe
Liver	Limiting alcohol	Too much alcohol causes liver disease4	Strong evidence
Liver	Assuming herbs and supplements are easy on the liver	Their share of serious liver injuries rose from 7% to 20%; 13% of non-bodybuilding cases ended in death or transplant6	Evidence says no, or unsafe
Immune	Fixing a true nutrient shortage	Shortages weaken immunity7	Strong evidence
Immune	Daily vitamin pills without a shortage	Probably little help against infections7	Evidence says no, or unsafe
Immune	Zinc lozenges at a cold’s start	Colds about two days shorter7	Promising but early
Immune	High-dose vitamin A in children with normal nutrition	66% more respiratory infections7	Evidence says no, or unsafe
Whole body	Seven or more hours of sleep	Lower risk of heart disease, stroke and dementia8	Strong evidence
Brain	Sleep as a nightly “brain wash”	Mouse studies disagree89	Promising but early
Skin	Lowering chronic stress	Stress slows healing; exercise and support help1112	Promising but early

Trusting the body often means doing less to it

Natural health’s faith in the body is well placed. Homeostasis is a fact of physiology, not a slogan².

The kindest support is often subtraction. Drink less alcohol. Skip tobacco. Take fewer pills and herbs you don’t need, and tell your clinician about the ones you keep. Then add the basics your systems run on: sleep, varied whole food, movement and people who have your back.

None of that comes in a bottle. That doesn’t make it less natural. It makes it more so.

Questions readers ask

The bottom line

Your body is built to clean, defend and repair itself, and science has a name for that steady balancing act. The best-documented ways to help are plain: sleep, varied food, enough nutrients, less alcohol, no tobacco and less stress.

Most products that promise to support those systems haven’t shown they help healthy people, and a few have harmed the very organs they claim to protect. Trust your body, feed it well, and ask for evidence before you pay for help it may not need.

Related reading

• Why supplement labels say ‘supports’ and never say ‘cures’
• What gets into supplements that isn’t on the label
• What happens when you don’t tell your doctor about supplements
• Fear sells health products, and five questions show when the threat is real
• Most heart attacks are preventable, and that doesn’t make treatment the enemy

Sources

1. National Center for Complementary and Integrative Health. “Naturopathy.” NIH, updated 2025. nccih.nih.gov
2. Senapathy K. “6 Scientists Who Shaped Physiology.” The Physiologist Magazine, American Physiological Society, 2025. physiology.org
3. National Institute of Diabetes and Digestive and Kidney Diseases. “Your Kidneys & How They Work.” NIH, reviewed 2018. niddk.nih.gov
4. MedlinePlus. “Liver Diseases.” National Library of Medicine, updated 2026. medlineplus.gov
5. National Center for Complementary and Integrative Health. “Detoxes and Cleanses: What You Need To Know.” NIH, updated 2025. nccih.nih.gov
6. Navarro VJ, Barnhart H, Bonkovsky HL, et al. “Liver Injury From Herbals and Dietary Supplements in the U.S. Drug-Induced Liver Injury Network.” Hepatology, 2014 (Duke University record). scholars.duke.edu
7. NIH Office of Dietary Supplements. “Dietary Supplements for Immune Function and Infectious Diseases: Fact Sheet for Health Professionals.” NIH, updated 2026. ods.od.nih.gov
8. NIH News in Health. “Good Sleep for Good Health.” National Institutes of Health, 2021. newsinhealth.nih.gov
9. UK Dementia Research Institute. “Scientists find sleep may not clear brain toxins as previously thought” (on Miao A, et al., Nature Neuroscience, 2024). UK DRI, 2024. ukdri.ac.uk
10. Columbia University, Go Ask Alice. “Why are my wounds healing more slowly?” Columbia Health, 2024. goaskalice.columbia.edu
11. Kiecolt-Glaser JK, et al. “Slowing of wound healing by psychological stress.” The Lancet, 1995 (journal index record). pubmed.ncbi.nlm.nih.gov
12. Christian LM, Graham JE, Padgett DA, Glaser R, Kiecolt-Glaser JK. “Stress and wound healing.” NeuroImmunoModulation, 2007 (Penn State record). pure.psu.edu
13. Electronic Code of Federal Regulations. 21 CFR 101.93, “Certain types of statements for dietary supplements.” U.S. Government. ecfr.gov
14. U.S. Food and Drug Administration. “Letter to the Dietary Supplement Industry on the DSHEA Disclaimer.” FDA, December 11, 2025. fda.gov
15. U.S. Food and Drug Administration. “How to Report a Problem with Dietary Supplements.” FDA, 2025. fda.gov