Body detoxification happens every day without special juices or teas: how your liver, kidneys, gut, lungs and skin do the job, what science says about "detoxification" diets and which everyday habits really matter.
"Detoxification", "cleansing" the body and flushing out toxins come up all the time in talk about special diets, juices, teas and supplements. But body detoxification isn't a programme you need to start on Monday: metabolism and the removal of unwanted substances go on constantly, every minute of the day.
In this article we draw on a scientific review of "detoxification" diets published in the Journal of Human Nutrition and Dietetics, and on information from the US National Center for Complementary and Integrative Health (NCCIH), Harvard Medical School's Harvard Health Publishing, the US National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), the European Food Safety Authority (EFSA) and the World Health Organization (WHO). You'll find the sources at the end of the article, and they are marked with numbers in the text, for example [1]. We explain how the gut works in more detail in "The gut: how it works and how to support it through diet".
What is body detoxification really?
In medicine, detoxification has a clear meaning. It refers to treating poisoning, or to a medically supervised process in which a person stops using alcohol or other addictive substances. That happens in a hospital or specialist centre, not in your kitchen.
In wellness marketing, the same word is used very loosely: for juice programmes, fasting, teas, supplements or colon cleansing. A scientific review noted that such programmes usually don't even name which toxins they remove or how this is supposed to happen [1]. If a product promises to "cleanse" your body but doesn't say of what, it's worth taking a critical look at that promise.
It's also worth knowing that being plant-based or containing fibre doesn't, on its own, mean a product removes toxins.
How does the body get rid of unwanted substances on its own?
The human body has several systems that constantly neutralise and remove substances it doesn't need. Harvard doctors stress that this job is best left to the kidneys, liver and other organs designed for it [4].
1. Liver
The liver processes many substances: it neutralises some metals and breaks down medicines and other chemicals so the body can get rid of them [3]. It also makes bile, which is needed to digest fats and through which some substances leave the body via the gut [6].
2. Kidneys
The kidneys filter about 140 litres of blood a day, yet only about 1–2 litres become urine [5]. This is how metabolic waste and excess fluid are removed, while the balance of water, salts and minerals is maintained [5].
3. Gut
The gut absorbs nutrients and water, while whatever isn't digested forms stools and leaves the body [6]. The gut wall contains immune cells that recognise foreign substances [3].
4. Lungs
When we breathe out, we get rid of carbon dioxide, which is produced as cells make energy. Nasal hairs and mucus trap particles so they don't travel deeper into the airways [3].
5. Skin
The skin is first and foremost a barrier against substances in the environment. Sweat is needed to regulate body temperature, but Harvard experts note that toxins are not, in any meaningful way, eliminated in sweat [3].
| Organ | What it does |
|---|---|
| Liver | Processes medicines and chemicals, makes bile [3, 6] |
| Kidneys | Filter blood, remove waste and excess fluid in urine [5] |
| Gut | Absorbs nutrients, removes what isn't digested [6] |
| Lungs | Remove carbon dioxide, trap particles [3] |
| Skin | Acts as a barrier, regulates temperature [3] |
What does science say about detoxification diets and juices?
In 2015, researchers A. V. Klein and H. Kiat reviewed popular "detoxification" diets and found no compelling evidence that they help remove toxins or manage weight [1]. The existing studies were small, poorly controlled and often relied on participants' own reports of how they felt. The authors concluded that health professionals should not recommend commercial "detoxification" diets until they have been properly studied [1].
In its 2025 overview, the NCCIH notes that there are few good-quality studies in people and no long-term studies at all [2]. On juice and "detoxification" diets, weight drops at first because of very low calorie intake, but it usually comes back once normal eating resumes [2]. Harvard doctors add that much of the early loss is fluid [3].
Body cleansing: what are the risks?
- Fluid and electrolyte imbalance. Drinking only water or herbal tea for several days while eating very little can upset electrolyte balance [2].
- Laxatives. Laxatives used in some programmes can cause diarrhoea, fluid loss and poorer absorption of nutrients [2].
- Juices from leafy greens and beetroot. They are high in oxalates, so they can be harmful for people prone to kidney stones [2]. Harvard doctors also mention a case of kidney failure linked to a juice cleanse [4].
- Unpasteurised juices. They can contain bacteria that are dangerous for children, older people and those with weakened immunity [2].
- Colon cleansing. There's no proven benefit for general health, and side effects can be serious [2, 4]. What's more, the very idea that stools "stick" to the walls of the colon is wrong [3].
- Too little protein and nutrients. Some programmes don't provide enough protein for most adults [1].
| Common promise | What research shows |
|---|---|
| "Removes built-up toxins" | No compelling evidence; toxins usually aren't even named [1] |
| "Helps you lose weight" | Weight drops due to low calories and fluid loss, then returns [2, 3] |
| "Strengthens the liver" | No evidence presented that cleanses strengthen the liver [4] |
| "Cleans out the colon" | No proven benefit of colon cleansing for general health [2, 4] |
Detoxification at home: what can you actually do every day?
If you want to support the organs that already handle body detoxification, Harvard doctors recommend simple things: a healthy diet, enough fluids, regular exercise, good sleep and recommended health check-ups [3]. It's not a quick programme, but these are the habits that work over time.
- Drink enough water. EFSA considers 2 litres a day adequate for women and 2.5 litres for men, including water from food [8]. Water is also needed for your kidneys to work [5].
- Eat more fibre. EFSA considers 25 g of fibre a day an adequate amount for normal bowel function in adults [7]. We explain how to reach it in "How much fibre do you need per day?".
- Eat a varied diet. Vegetables, fruit, berries, wholegrains, pulses, nuts and seeds. Variety matters more than any single "super" food [12].
- Get enough sleep. Adults are advised to sleep 7 or more hours a night [11].
- Limit alcohol. The WHO stresses that there is no safe level of alcohol for health: the less, the better [9].
- Move. The WHO recommends that adults get 150–300 minutes of moderate-intensity physical activity a week [10].
- Don't smoke. It's one of the most important choices for your lungs and your health overall.
Where does fibre fit in?
Fibre is the part of plant food that human enzymes can't break down, so it reaches the large intestine, where gut bacteria ferment part of it [6]. It adds bulk to stools and helps keep bowel movements regular. That is exactly what EFSA based its fibre intake on [7]. However, fibre shouldn't be called a natural body "cleanser", nor should anyone claim it removes built-up toxins. It's part of an everyday diet, not a "cleansing" tool.
Is more fibre always better?
Not necessarily. If you've been eating little fibre and suddenly increase it, you may get bloating or wind. Increase it gradually and drink enough fluids. We cover this in more detail in "Bloating: common causes and everyday habits".
Important: this research is about the human body and nutrition in general. It does not describe the effects of any fruttberry product and does not replace advice from a doctor.
When to see a doctor
If you feel unwell, look for answers from a doctor, not a "detoxification" programme. Harvard doctors advise seeing a doctor if any of the following lasts for days or weeks [3]:
- Fatigue. Especially if it's unusual and doesn't ease with rest.
- Pallor. A noticeable change in skin colour.
- Unexplained weight change. Weight going down or up for no clear reason.
- Changes in bowel habits. A pattern that's unusual for you, or blood in your stools.
- Breathing problems. Shortness of breath or a cough that won't go away.
If you have a chronic condition, especially kidney or heart disease, take medication, are pregnant or breastfeeding, don't start fasting, juice programmes or colon cleansing without talking to your doctor first [2]. Don't change or stop your medication without your doctor.
Fibre for your everyday: fruttberry fibre blend
We created fruttberry out of our own need: we wanted a fibre blend that would be enjoyable to drink every day. If you don't get enough fibre from food, the blend can help top up your daily intake alongside a varied diet.
Ingredients
- Psyllium husk (Plantago ovata) is the base of the blend.
- Agave inulin is a soluble fibre that is fermented in the gut.
- Glucomannan from konjac tubers is another soluble fibre.
- Freeze-dried strawberries (12%) and blackcurrants (8%) provide flavour and colour.
How much fibre is in one teaspoon?
100 g of the blend contains 77 g of fibre. In an independent test by the KTU Food Institute, our sample contained as much as 84.4 g of fibre per 100 g. One teaspoon (5 g) provides about 3.86 g of fibre and only 11 kcal. The blend contains no added sugar, gluten, lactose or preservatives, and it is suitable for vegans. It tastes of strawberries and blackcurrants.
Stir one teaspoon into 200–250 ml of water and drink it straight away, then increase the amount every 3–4 days. Psyllium and glucomannan swell, so always take the blend with enough water: with too little fluid there is a risk of choking. If you have difficulty swallowing, don't take this kind of fibre. Don't exceed the amount stated on the pack.
All fruttberry dietary fibre products in one place.
Frequently asked questions about body detoxification
Does the body need special detoxification?
Not if you're healthy. Body detoxification is carried out constantly by the liver, kidneys, gut, lungs and skin [3, 4]. There's no compelling evidence that special "detoxification" diets remove toxins [1, 2].
Do detoxification juices work?
Research doesn't show that juices remove toxins. Weight drops during juice programmes because of low calorie intake and usually comes back [2]. Some juices can also be risky for people prone to kidney stones [2].
How can I do detoxification at home safely?
The best "detoxification at home" is everyday habits: enough water, fibre and varied plant foods, good sleep, movement and as little alcohol as possible [3, 7–11]. It's best to avoid fasting or colon cleansing without a doctor's advice [2].
Does fibre "clean out" the gut?
That description isn't accurate. Fibre adds bulk to stools and helps keep bowel movements regular, and gut bacteria ferment part of it [6, 7]. That's a normal part of digestion, not "cleansing".
How long does a body cleanse take?
It never starts or stops: your kidneys, liver and other organs work constantly, every day [3, 5]. That's why long-term habits matter more than a short programme lasting a few days.
Sources
- Klein AV, Kiat H. Detox diets for toxin elimination and weight management: a critical review of the evidence. Journal of Human Nutrition and Dietetics. 2015;28(6):675–686.
- National Center for Complementary and Integrative Health (NCCIH). "Detoxes" and "Cleanses": What You Need To Know. Updated 2025.
- Harvard Health Publishing. The dubious practice of detox. 2008.
- Shmerling RH. Harvard Health Ad Watch: What's being cleansed in a detox cleanse? Harvard Health Publishing. 2020.
- National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK). Your Kidneys & How They Work. 2018.
- National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK). Your Digestive System & How It Works. 2017.
- EFSA Panel on Dietetic Products, Nutrition and Allergies. Scientific Opinion on Dietary Reference Values for carbohydrates and dietary fibre. EFSA Journal. 2010;8(3):1462.
- European Food Safety Authority (EFSA). EFSA sets European dietary reference values for nutrient intakes. 2010.
- World Health Organization (WHO). No level of alcohol consumption is safe for our health. 2023.
- World Health Organization (WHO) Europe. Physical activity. 2021.
- Centers for Disease Control and Prevention (CDC). About Sleep. 2024.
- NHS. How to get more fibre into your diet. Reviewed 2026.
The information provided is general in nature and does not replace advice from a doctor or dietitian. The scientific data relate to fibre and nutrition in general and do not describe the properties of any specific product. If you have a chronic condition, take medication, are pregnant or breastfeeding, talk to a healthcare professional before starting any food supplement. A food supplement is not a substitute for a varied and balanced diet.
