Your body has plenty of ways to cleanse itself. Here’s how to help it along.
If you’ve been taking part in the usual excesses of the festive period, you may now be considering a detoxification (or “detox”) diet for a few weeks to try to cleanse your body. But from juice fasts to the many other energy or protein restricted detox diets, there’s often little evidence that they actually work to eliminate toxins or to control people’s weight.
Even the word “toxins”, which generally refers to substances poisonous to organisms, is frequently used in a hazy, undefined way when these diets are promoted. And while there are certainly substances in our environment that may harm us that, our bodies have a whole host of incredibly effective ways to get rid of them naturally.
Here’s some of the ways you can help these processes along.
Eat more fibre
The vast majority of us eat far too little fibre. In the US, some 97% of men and 90% of women do not reach the suggested intake. In fact, most Americans eat less than half of what’s recommended.
Fibre has a major impact on our health. It helps lower inflammation, strengthens the immune system and can impact brain functioning, mood and cognition. It has also been shown to reduce the risk of many chronic diseases including cardiovascular diseases, type 2 diabetes, colon cancer and inflammation. The way fibre helps us cleanse our bodies is one reason for all these beneficial impacts.
For starters, fibre increases the size and weight of stools, making them softer and easier to pass and limiting the time harmful substances are in contact with the bowel.
Research also shows fibre can act as a kind of magnet, binding to toxins and other substances and helping to remove them from the body. A 2015 study, for example, found that fibre binds toxic ions such as lead, arsenic and copper, aiding in their excretion. Fibre also appears to help the body get rid of bile acids, lowering cholesterol and thus decreasing the risk of cardiovascular disease. Studies also show that some fibres may actually directly enhance the detoxification of carcinogens and inhibit the growth of cancer cells, although this is an early area of research.
Fibre may even help us cleanse out “forever chemicals“, a set of long-lasting and potentially harmful human-made substances. Small scale studies in mice and humans have found that taking a fibre supplement with meals appears to reduce their levels in the body, although this is still an early area of research.
Fibre also helps protect the kidneys and liver – both crucial for removing toxins from the body – by protecting them from harmful bacteria and helping beneficial bacteria to grow.
To increase your fibre intake, plant-based foods are your best bet. Dried fruits like apricots, leafy vegetables like spinach and legumes like a chickpeas, lentils and beans are all high in fibre, as are porridge oats and wholewheat bread and pasta. Snack on apples, berries, nuts, seeds, popcorn or roasted pulses. Lots of variety is key, since there are lots of different fibres with different properties.
Drink more water
Water helps to remove toxins from the body by helping the kidneys and liver to excrete waste.
The kidneys, for instance, use water to flush out toxins such as sodium and urea. Dehydration can cause waste to build up. Over time, even mild dehydration can increase the risk of kidney damage and make their waste clearance less effective. Drinking enough water can also help protect your kidneys in the long run – one review of 18 randomised controlled trials found that drinking more water could help reduce the risk of kidney stones, among other benefits.
So how much water is enough to help your body perform these essential functions? The widespread advice of eight glasses of water (around two litres) is outdated, stemming from advice in 1945 which included food as a source of water. Instead, around 1.5 to 1.8 litres per day (six to seven-and-a-half glasses) is enough for most people.
Water, lower-fat milk and sugar-free drinks, including tea and coffee all count towards this fluid intake. (Read more about how much water you really need in this story by Jessica Brown.)
Help your lungs
There’s been a proliferation of products claiming to cleanse your lungs, sometimes within days. The American Lung Association (ALA) warns against trusting such “quick fixes”, noting some of these detox remedies can be dangerous.
There is something you can do to help promote your lungs’ natural, self-cleaning capacity though: avoid pollutants in the first place. If you smoke or vape, quitting is the most important step you can take – as well as making sure to avoid secondhand smoke.
The ALA also advises keeping your indoor air as clean as possible: including by avoiding the use of cleaning products or air fresheners containing volatile organic compounds (VOCs) or fragrances, as well as steering clear of candles, fireplaces and natural gas. It also recommends vacuuming with a HEPA vacuum cleaner to reduce dust and allergens. (Read more about the most effective ways to reduce indoor pollutants).
Cardiovascular exercise also helps your overall lung health, for example by reducing airway inflammation and improving the strength and endurance of breathing muscles. You can also promote your lung’s health by exercising them directly – including by playing a wind instrument. (Read more about how you can get your lungs into better shape.)
Enjoy your sleep
It brings new meaning to “brain washing” – every night an influx of fluid flushes through channels in the spaces around our brain cells to whisk away our cerebral waste.
This waste – excess proteins and other molecules including the beta-amyloids involved in Alzheimer’s disease – is produced by our brain cells as they work and builds up through the day. Some of it can be broken down and carried across the protective barrier between our blood vessels and the brain. The rest, however, accumulates in the spaces between our neurons.
Recent research has suggested that cerebrospinal fluid – the colourless liquid that protects our spine and brain – is pumped into these extracellular spaces as we pass through the different stages of sleep, washing away these potentially toxic molecules. Micro-arousals during light sleep in particular cause surges of cerebrospinal fluid to flow across multiple brain regions.
Some scientists think that the sleep-hormone melatonin in the cerebrospinal fluid also acts like a detergent that helps to mop up some of the more pernicious waste. There is no evidence that taking supplements will improve this process, however.
Sleep loss, meanwhile, has been shown to impair the function of the blood-brain barrier, which can affect our brains’ ability to clear itself of potentially neurotoxic byproducts. Even getting slightly less sleep than our bodies need – typically around seven hours, although this does vary from person to person – can affect our brain’s ability to clear itself of waste material.
All of this can have an impact on our brains the next day. Without this nightly tune up, our cognitive capabilities can slow down and our judgement can become impaired.
Some researchers have been exploring whether it might be possible to recreate the waste-removal processes of sleep while we are awake, including experimenting with a technology known as transcranial radiofrequency treatment, which delivers radio waves to the entire brain.
Others, however, believe it is better to focus on lifestyle choices to enhance sleep’s natural toxin removal system. Some studies have suggested that sleeping on your right side can enhance the clearance of toxins by cerebrospinal fluid (although it is worth noting that the average person changes sleeping position around 11 times per night). Drinking large amounts of alcohol has also been found to have adverse effects on sleep, while regular exercise seems to improve it. Much of this research, however, is still emerging and has been performed in studies with animals, so needs to be properly validated in humans before any firm recommendations can be made.
Keep fit
You can help rid your body of toxins through exercise. But not through sweating.
Hot yoga sessions, sitting in saunas and working out in heated studios are increasingly popular activities, but scientists are sceptical about claims that you can “sweat out toxins“. Davide Filingeri, a physiology professor at the University of Southampton, told the BBC in October 2025 that he wasn’t aware of “any strong empirical evidence” this is true, while Sarah Everts, a chemist and author of The Joy of Sweat, described the claim as “completely bananas”.
Sweat is mostly water and its primary function is to regulate our body temperature and cool us down. The liver and kidneys are the main pathways for removing toxins from the body and research shows that exercise boosts blood flow to these organs and enables them to filter waste more effectively.
Excess fat impairs the liver’s ability to filter toxins, and research shows exercise can help reduce it. In one study of patients with non-alcoholic fatty liver disease, which can cause long-term liver damage and scarring, resistance training and aerobic exercise were found to reduce the liver’s fat content. Another study found long-term high-intensity interval training reduces the decline of kidney function in older adults. Kidney Research UK recommends brisk walking, swimming and cycling, as among of the best exercises for kidney health. Even gardening, housework or taking the stairs rather than the lift can help.
Of course, for all these processes as well as most other changes in behaviour for health, it’s the long term that counts. Experts also point out, for example, that while taking part in Dry January may have some short-term health benefits, drinking within alcohol guidelines for the whole year is far more important for our health. Permanently adopting a Mediterranean diet, meanwhile, is often cited by scientists as the healthiest change you can make to your eating habits. (Read more about some of the best lifestyle tweaks for living well for longer).
So by all means make a push for a science-backed change in this month – but if you want to see real health benefits, you may need to stick with it far longer than just a few weeks.
