Nutrition: Dealing with cancer treatment side effects -Constipation and diarrhoea

Friday 04 May 2018

I see many many people asking for advice about coping with the side effects of medical treatment whether it be as a result of surgery, chemotherapy, radiotherapy, some drugs or a combination of some of these.  Side effects can be unsettling and uncomfortable. If you are at all concerned about the side effects you may be experiencing then it is important to contact your medical team, but there are some measures that you can take to help relieve some of these frustrating problems yourself. I thought I would look at some of these in the next couple of blogs.

Two of the most common side effects (other than fatigue) are having constipation or diarrhoea. Both can be exhausting and quite debilitating.

Coping with constipation
Constipation can occur as a side effect of some drugs, particularly those given for pain relief. Here are some suggestions that are recommended to help prevent or deal with constipation. Quite obviously if you have had bowel surgery then be selective about which you choose and talk to your medical team for individual advice.

  • Keep hydrated The first and most fundamental action would be to try and drink more fluid, particularly water or warm herbal teas. One function of the large intestine is to absorb water to make the waste solids soft and easy to pass. Insufficient water can lead to hard dry stools that are difficult to pass and this can cause a great deal of pain and discomfort. It is recommended that you drink between 1 ½ and 2 litres of water a day. (unless you have been advised by your Dr  to restrict fluids) That equates to about 8 large tumblers full. This may be hard for some but any is better than nothing. It is worth noting that coffee, caffeinated drinks like cola and alcohol are diuretics and can cause dehydration so are best avoided.
  • Fibre It is also a good idea to try and increase the amount of fibre in your food. (unless you have been advised by your Dr to restrict it)  Fibre comes from foods like vegetables, fruits, wholegrain cereals like porridge and wholemeal bread. Fibre will absorb the fluid, bulk up the stools making them soft and easy to pass. If you are able, increasing the amount of raw food to get maximum fibre.
  • Flax seeds Apart from the two fundamental steps that I have mentioned above, I have had very good results recommending ground flax seeds. These can be bought from most health food shops.  I recommend starting with 2 tablespoons a day sprinkled on cereal, porridge, mixed into yogurt or simply blended into water and drunk. It is important to have plenty to drink if using ground flax seeds because they will bulk once inside. They encourage good peristalsis, absorb water and soften stools. I always suggest giving the ground flax seeds up to 3 days to become effective as they are natural and not a laxative. The added benefit of these is that they are rich in the essential fatty acid omega 3 which has many health benefit including being a good anti inflammatory. Cancer is an inflammatory process.
  • Pysllium husks An alternative is to try some pysllium husks either ground or whole. If ground take 1 -2 tsps  with a little water 2-3 times a day. Again drink plenty of fluid if you choose to use these. Or sprinkle a few teaspoons of whole husks onto cereal. The amount can be increased if necessary.
  • Oat or rice bran used with cereal in the morning is also very effective . They hold more than 3 times their weight in water.
  • Prunes and prune juice are a good source of sorbitol which is a natural laxative.
  • Exercise Cancer treatments may leave you feeling drained and tired, exercise becomes a low priority consequently muscles including those of the abdomen become sluggish so if possible some exercise would be a good idea. Even if it is a ten minute walk.
  • It’s personal It is always important to remember that bowels are like fingerprints they are unique to that person and what may be effective for one person will not work as well for another. It is a little bit of trial and error. The measures that I have mentioned above I have had good results with clinically, in my practice.

Coping with diarrhoea.
Chemotherapy can have a toxic effect on the lining of the intestines which can in turn reduce the amount of digestive enzymes produced. This causes undigested food to move into the colon where it encourages diarrhoea. Some drugs increase the rate of peristalsis and the rate of transit time through the colon which gives less time for absorption of water.

  • Some foods can also cause loose stools particularly milk and milk products because treatment can cause a temporary loss of the enzyme lactase which is essential for the proper digestion of milk. So it may be a good idea to avoid these foods. There are many alternative milks on the market like rice milk, oatley milk or almond milk which can all be bought from major super markets which do not contain lactose.
  • Avoid raw foods and those that can be gassy. Foods like peas, beans and lentils and vegetables from the cabbage family.
  • Hot foods may stimulate peristalsis so eat cool or room temperature foods.
  • Foods such as coffee, alcohol, carbonated drinks and highly spiced foods can irritate the gut lining and may compound the problem.
  • Avoid prunes and prune juice as they contain a natural laxative and any foods containing sorbitol which is found in sugar free and diabetic foods.
  • Sugar and sugary foods will also exacerbate the problem.
  • Try to eat bland foods like potato and potato soup, rice or oat porridge, rice pudding made with rice milk, omelettes, mashed ripe bananas etc. and eat little and often so that the digestive system is not overloaded.
  • Coconut water, which you can buy from health food shops in individual cartons, is excellent for replacing the electrolytes that can be lost from the body in cases of severe diarrhoea. Or a nice warm fresh vegetable broth should also help.
  • Something that comes highly recommended is the use of L Glutamine powder (used in some hospital settings). L Glutamine is an amino acid that is a building block of protein. L Glutamine is the most abundant amino acid in the body particularly in the muscles and lining of the digestive tract. It will help repair the lining of the digestive tract. I would recommend 1 tsp mixed with a little water 3 times a day on an empty stomach. Ideally 30 minutes before eating.

Diarrhoea will also cause disruption of the normal bowel ecology. i.e. the bacterial population that resides in our bowel. When it is disrupted it can cause diarrhoea and will also affect our immune system. This is because 70% of our immune cells reside in our gut. It is important to replace these by taking a good quality probiotic capsule measured in billions!!!!! Sounds enormous doesn’t it, I would recommend 8-15 billion strength. Please note that if you are having treatment to check with your oncologist that he or she is happy. Some will recommend them some will not. If you do take one then have one first thing in the morning 10 minutes before food. And always keep them in the fridge.

This blog seems all a bit clinical I am afraid but it seems the best way to deal with the subject. I hope that it is of some help to those of you who are in need of help with either diarrhoea or constipation. One thing that I have learnt very quickly from writing this blog is how to spell diarrhoea!!!!

Original blog written by Caroline November 2012

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