Camden South Family Doctors > News > FOOD BYTES #3: Are Bowel Cleanses Necessary For A Healthy Bowel?

FOOD BYTES #3: Are Bowel Cleanses Necessary For A Healthy Bowel?

Did you know that the human large bowel is home to over 11 trillion bacteria (that’s more than all of the cells in your body!). These bacteria play important roles in nutrient utilisation, vitamin synthesis, energy metabolism and immune responses. More and more research is showing links between poor gut health (known as gut dysbiosis) and several diseases/health issues, including obesity, liver disease, IBS and cancers.

Bowel cleanses are marketed under many guises, including detox diets, herbal products and colonic irrigation (that sounds fun doesn’t it!) and are purported to have a plethora of health benefits, including promotion of weight loss, resolution of digestive issues, and prevention of colon cancer. But are they more hype than they are healthy?

Cleanse products ingredients are typically from plants that have some pharmacologic properties. Some whole food cleanse ingredients, such as psyllium and flax have shown some positive effects in maintaining bowel health, but the evidence is inconclusive and these ingredients may be harmful if consumed in excessive quantities (NB a little flax or psyllium sprinkled over your porridge is perfectly fine). Cleanses made from herbal products (such as banana leaf extract, yerba mate, Ma Huang, aloe and milk thistle to name a few) and from juices (such as mangosteen juice) have insufficient evidence from clinical trials on humans that they are effective.
Ingredients found in these cleanses may also cause adverse side effects in some individuals, and others may be life-threatening or unsafe for certain populations or individuals with certain diseases. Cleanse diets are not recommended for: pregnant or breastfeeding women, children, individuals about to have surgery, people with high blood pressure, allergies or bleeding disorders.
Additionally, commercial detox diets tend to be expensive or if you are making your own at home, often call for expensive ingredients. Most of these diets also specify consumption of less processed foods (thrown in with the exclusion of whole food groups such as dairy and red meat) in conjunction with the detox product. I’m all for nourishing your body with more plant-based foods (and yes, eating less red meat will reduce your risk of colon cancer-the research to support this is very strong), however, excluding whole food groups is often unnecessary and can put you at risk of nutritional deficiencies if you do not know how to substitute these foods appropriately.

What about probiotics and prebiotics?

Research has demonstrated that probiotics reduce and improve symptoms of IBS. Abdominal pain is significantly reduced with probiotic intake. All probiotic strains studied appear to show benefit, however L. rhamnosus GG and B. infantis are the only two probiotic strains tested in multiple trials. Probiotics appear to be safe, with no adverse reactions reported to date however the optimal dosage, duration and probiotic strain have yet to be determined. Generally speaking, Yakult and Inner Health Plus would be suitable for most people. Food sources of probiotics include yoghurt and other fermented foods such as sauerkraut, miso soup and sourdough bread
Prebiotics are essentially ‘food’ for the gut bacteria and are found in common foods like bananas, onions and garlic. Healthier foods tend to support growth of beneficial gut bacteria and inhibit growth of the less helpful bacteria. The research is still developing in their use and efficacy in various diseases, but including these foods as part of a balanced diet can only be good thing!
In summary, due to the large hole that exists in the research to support these detox diets, I would recommend avoiding detox diets altogether and choosing the approach backed by an overwhelming evidence base. That is to nourish your body with more fruit and vegetables, wholegrains, legumes, choose lean meats/poultry/fish and dairy products (or alternatives) in moderation and in portions appropriate for your needs, eat for enjoyment and nourishment and drink plenty of water (oh, and move more!). If you think your gut heath really needs a little extra help, I’d say go for a daily probiotic (and don’t forget those prebiotic foods to feed them!)

NB. I would always recommend that if you have digestive issues, first seek professional advice from your GP (or get a referral to a gastroenterologist) for proper investigation of issues such as IBS, Chron’s disease, coeliac disease or bowel cancer. A proper diagnosis can make all the difference to effectively managing your condition!
Once a diagnosis is made, an Accredited Practicing Dietitian can assist in the dietary management of your gastrointestinal issue and an Exercise Physiologist can tailor an exercise program to suit your needs and motivate you to get moving!
June is Bowel Cancer Awareness month- visit for more information about this great awareness initiative.

If you have been diagnosed with a gastrointestinal disorder, or if you would like to know more about optimal nutrition and exercise for a healthy gut, book an appointment with our Accredited Practicing Dietitian and Exercise Physiologist for expert tailored nutrition and exercise advice at

Written by Belinda Russo (Accredited Practicing Dietitian and Exercise Physiologist from Tiny Tummies Nutrition.


1. Acosta RD, Cash BD. Clinical effects of colonic cleansing for general health promotion: a systematic review. Am J Gastroenterol. 2009 Nov;104(11):2830-6 . In: Practice-based Evidence in Nutrition [PEN] cited 2016 21st June]. Available from: Access only by subscription. Free trials available.

2. Douglas LC, Sanders ME. Probiotics and prebiotics in dietetics practice. J Am Diet Assoc. 2008 Mar [cited 2009 1 Mar];108(3):510-21. In: Practice-based Evidence in Nutrition [PEN] cited 2016 21st June]. Available from: <a href=” Access only by subscription. Free trials available.