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Should I “detox” after cancer treatment?

During cancer treatment, the body is exposed to many toxins. The most obvious is chemotherapy, but there are others, such as anaesthesia, analgesia and contrast dyes used in scans. There is also likely to be cellular debris which has accumulated as the result of radiotherapy and chemotherapy killing cancer cells, and this also needs to be removed from the body.

Should you, then, be trying to actively detoxify after treatment is finished?

What is detoxification?

Detoxification is a process that goes on continuously in our bodies to package up and remove compounds that are no longer needed. These can be the breakdown products of our metabolism, our own used hormones, as well as toxins such as chemicals and heavy metals (or chemotherapy!) to which we have been exposed. The main organs of detoxification are:

  • liver

  • kidneys

  • colon

  • skin

  • lymphatic system

  • lungs

The body does and amazing job of continually removing toxins from our body. Nevertheless, the toxic load to which we are exposed nowadays is greater than that which we have evolved to deal with. Thousands of chemicals have been introduced into our environment in modern times and their combined effects on us have not been tested. One study(1) found that children had higher levels of pesticides in their urine when they ate conventionally grown food than when they switched to an organic diet. This is evidence that our bodies do need to excrete these chemicals. Other toxins include heavy metals, air pollution, mycotoxins from mould, and persistent organic pollutants. Some of these act as endocrine disruptors, mimicking the effects of oestrogen in the body.

There can be reasons why our body doesn’t detoxify as efficiently as it could do. For example, being constipated and therefore being unable to excrete toxins in the stool, being deficient in certain nutrients that are needed for liver detoxification, or simply being dehydrated. We also have individual genetic variations which can affect our ability to detoxify effectively.

Should there be a special detox after cancer treatment?

After cancer treatment, this balance between the toxins we are exposed to and our ability to detoxify from them (“toxins in, toxins out”, if you like) can certainly become compromised. However, trying to force detoxification just after active treatment may not be wise. Intense detoxification programmes can put quite a stress on the body, at a time when it is just recovering from a period of intense emotional and physiological stress. If you are taking ongoing medication such as Tamoxifen or an aromatase inhibitor, it is also important that you do not inadvertently speed up or slow down the rate at which these are eliminated from your body.

Many toxins that we are exposed to are fat soluble rather than water soluble, and they therefore get stored in fat tissue in the body. This has the beneficial effect of keeping the toxins away from organs where they could do more harm, although toxin accumulation in fatty tissue is linked with obesity(2). If we try to “force” detoxification without being under the guidance of a healthcare practitioner, we risk mobilising those toxins into the bloodstream without ensuring that they can be eliminated – this could lead to more symptoms of toxicity.

There is, however, a lot that you can do to redress the toxin imbalance. The first step is to minimise your toxin exposure as much as you can. That’s a topic for an entirely separate post! The second step is to provide sensible food and lifestyle support for your detoxification organs so that they have everything that they need to do their jobs effectively, and that is what this post is about. Adopting a diet and lifestyle that allows your body to release toxins efficiently as it needs to is much gentler and more sensible than undergoing an intense detoxification programme.

The Colon

Many toxins are fat soluble and are excreted in the stool. Being constipated can result in toxins not only not being eliminated from the body, but recirculating around the body. The aim is to have at least one good, easy to pass bowel movement per day that results in a feeling of complete evacuation.

There are lots of potential causes of constipation, but in many cases it can be resolved by paying attention to hydration, exercise and fibre. Since bowel movements often happen first thing in the morning, yet we all wake up dehydrated after the night, it can be very helpful to drink 2 mugs of warm water as soon as you wake up. If you are constipated, aim for at least 2 litres per day of water or herbal teas. If you are still constipated, you may need more fluid than this. Exercise encourages the rhythmic contractions of the colon that help to push the stool through, so movement is also helpful – but I am sure you all have this covered! Finally, make sure that you get plenty of fibre from vegetables, fruit, whole grains, legumes, nuts and seeds. Foods and fibres that can be particularly helpful in relieving constipation include kiwi fruit, beetroot, rhubarb, chia seeds (with plenty of water) and psyllium husk.

If you are still constipated, consult with a healthcare practitioner.

The Liver

The liver is key in the detoxification process, and can be readily influenced by food.

Detoxification in the liver is a complex process that consists of three phases (although we will only explore the first two here). Phase I involves toxins undergoing chemical reactions so that they are primed for Phase II. The rate of Phase I is partly influenced by genetics, but also in part by the foods that we eat.

In Phase II liver detox, reactions occur which result in fat-soluble toxins being bound to other compounds so that they become water-soluble and can be excreted in the urine or stool. These compounds come from the food that we eat. It is important that Phase II does not run more slowly than Phase I, or else we can get a build-up of intermediary toxins.

Once bound, toxins are put into the bile, which is excreted as part of the stool. Bile secretion and flow are influenced by food too!

Many of the foods that support the liver’s detoxification processes are provided by eating a diverse plant-based diet. The cruciferous vegetable family (kale, broccoli, cabbage, cauliflower etc) deserve a special mention as they modulate Phase I and upregulate Phase II liver detoxification(3). Other foods that support liver detoxification include eggs, green leafy vegetables, citrus fruits, the onion family and yellow/orange vegetables. We also need some vitamin B12, which is only found in animal foods or in supplements. Adequate protein is important, which is why juice fasting isn’t advisable for more than a couple of days. Bitter leaves such as rocket and radicchio also upregulate detoxification –paradoxically because they contain very small amounts of toxic compounds. These stimulate the liver to increase its activity, and the resulting detox more than compensates for the toxins they contain.

Foods which encourage healthy bile flow include beetroot, artichoke, turmeric and bitter leaves again. Staying hydrated is also important as the bile is around 95% water.

Good hydration is essential to help the kidneys to remove water-soluble toxins too.

Skin and lymphatic system

We can take some of the pressure off the liver and kidneys by supporting detoxification through the skin, via sweating. Certain toxins are more readily excreted via the sweat than in urine or the stool(4). The most effective way of promoting toxin excretion through sweat is exercising. If this is not possible, or if you want to do more in addition to exercising, then saunas can be helpful.

The lymphatic system is often forgotten, but it too plays an important role by removing toxins and debris from around the cells and taking these to lymph nodes to be removed. The lymphatic system is a circulatory system that in many ways is like the blood circulatory system, but whereas the bloodstream has the heart as a pump, the lymphatic system has no pump. Instead, it relies on the contractions of our muscles to pump it – another reason why exercise is so important. You can encourage lymph flow by having manual lymphatic drainage massage or by doing skin brushing. (Please consult a specialist for either of these if you have had lymph nodes removed.) An anti-inflammatory diet is key in keeping the lymphatic system healthy, since chronic inflammation can result in congestion. Use culinary herbs and spices liberally. Avoid ultra-processed foods which contain additives and preservatives, as this will reduce the work that the lymphatic system has to do. Lastly, good hydration is again fundamental.

In this post I’ve shared the idea that you don’t need to undergo an intensive or extreme detoxification programme in order to help your body to detoxify. Instead, it’s much safer to eat in a way which supports and upregulates the body’s own detoxification mechanisms, so that your body has the resources to can get on with what it does naturally.

Nutrition advice to support detox organs after cancer
Detox after cancer


(1) Lu, C., Toepel, K., Irish, R. et al. (2006). ‘Organic Diets Significantly Lower Children’s Dietary Exposure to Organophosphorus Pesticides’, Environmental Health Perspectives, 114(2), pp260-263. Available at (Accessed 31 August 2023).

(2) Jackson, E., Shoemaker, R., Larian, N. et al. (2017). ‘Adipose Tissue as a Site of Toxin Accumulation’, Comprehensive Physiology, 7(4), pp1085-1135. Available at (Accessed 31 August 2023).

(3) Saw, C.L.-L., Cintron, M., Wu, T.-Y. et al. (2011). ‘Pharmacodynamics of dietary phytochemical indoles I3C and DIM: Induction of Nrf2-mediated Phase II drug metabolizing and antioxidant genes and synergism with isothiocyanates’, Biopharmaceutics and Drug Disposition, 32(5), pp289-300. Available at (Accessed 24 July 2023).

(4) Sears, M.E., Kerr, K.J. and Bray, R.I. (2012). ‘Arsenic, Cadmium, Lead, and Mercury in Sweat: A Systematic Review’, Journal of Environmental and Public Health, 2012: 184745. Available at (Accessed 1 September 2023).

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1 Comment

Unknown member
Sep 06, 2023

Such an interesting & informative article, thank you

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