Nutrition before cancer treatment begins

Thursday 03 May 2018

People I see waiting to start chemotherapy are often concerned about how they can get themselves in the best possible shape so that they can hopefully cope with the treatment better and secondly what practical things can they do to prepare.

Taking control of what you can
These are both very good points not only for health but also to make the visitor feel that they are taking control of the situation and doing the best that they can. I always think it is best to control what you can control and not to worry about things out of your control.

How can eating well pre treatment help?
If we look at food and diet first. There is plenty of good evidence that shows that people who can eat well before treatment tend to cope with the treatment better, suffer fewer side effects and recover more quickly. These are all very sound reasons to try and adopt or maintain a healthy eating pattern while keeping weight stable. Perhaps the most important part of a healthy eating plan is that it helps to support the immune system. The immune system does get adversely affected by the treatment itself so to make it as strong and well- functioning as possible prior to treatment certainly should help.

Boosting the immune system

The immune system is very complex with many different cells carrying out different roles to protect the body from foreign invasion of toxins, bacteria and viruses etc. Because of its complexity it relies on a wide range of nutrients from a wide selection of foods. Rather than list all of the nutrients it may be more useful to look at the foods that would support it

Foods to support the immune system

  • Fresh fruits and vegetables in abundance using as much colour and variety as you can. The coloured pigments in the different colours all contain different vitamins, minerals and phytonutrients, which have been shown to support the immune function. Using fresh fruits and vegetables that are in season will not only be cheaper but they will be at their peak nutritionally. Use them raw, steamed, stir fried, oven roasted using olive oil, into soups, and vegetable based sauces that can be used served over chicken or fish or with lentils and beans added.
  • Protein rich foods are essential either in the form of lean animal foods like chicken, fish and eggs or using pulses like peas, beans and lentils and soya. Most writers and researchers of nutrition and cancer lean very much towards the vegetable forms of protein but personally I think that a mixture of both, lean animal and some vegetable seems to suit most people. I do think from observation that some people seem to do better using animal forms of protein. I call them the hunter gatherer types.
  • Amino acids There are 3 amino acids (building blocks of protein) that are essential for the production of Glutathione which is essential for boosting the immune system and the body’s major natural antioxidant. Protein is also essential to prevent muscle mass loss which can be a problem when people who have cancer lose weight.
  • Essential fatty acids (omega 3 and omega 6) are also important for the immune system. They are found in oily types of fish, nuts and seeds and nut and seed butters and their oils. It is generally advised to try and eat oily types of fish 3 times a week to get sufficient omega 3. For those who do not like or eat fish than plenty of seeds particularly pumpkin and flax seeds and walnuts in particular would be a good idea. Omega 3 foods are important for supporting the body’s immune response.
  • Vitamin D has been shown to be very important. There is a huge amount of good research on the importance of vitamin D and immune function. Vitamin D comes from oily fish, eggs, nuts and seeds and fortified cereals. The sunshine is of course the best way to get it. The role of vitamin D has been shown to benefit from the inclusion of vitamin K which is found abundantly in green leafy vegetables especially kale.
  • Wholegrain cereals like oats, quinoa, whole meal bread and pasta and rice for a good supply of energy and to make a balanced diet. These whole grain products supply valuable B vitamins, soluble fibre to support good bowel health and give a feeling of comfort in the diet.

There are some foods that have been singled out as being very beneficial to the immune system, some books and articles emphasis some more than others. I have listed them here. When considering this long list I believe that rather than be a slave to one or the other,  to consider them as important, but as part of a balanced healthy diet.

  • Shitaki and maitake mushrooms, green tea, berry fruits, turmeric, broccoli. Pomegranate juice, Manuka honey turmeric and garlic.
  • It is important to remember that a good mixed diet is recommended because all of the different nutrients found in different foods all have very specific interactions with each other which can be very complex. To give you a few examples;
  • Magnesium is necessary for the conversion of vitamin B 1 (thiamine) into its active form, and vitamin C helps thiamine absorption.
  • Vitamin C increases the absorption of iron and improves the stability of vitamin E.

So you can see how intricate their relationships are and there are hundreds that could be quoted.


What depletes the immune system ?   Foods to try to avoid

Apart from understanding how to support the immune system it is equally as important to know what can deplete the immune system and to try and avoid these foods.

  • Sugar There is strong evidence that sugar has a negative effect on the immune system. When white blood cells are exposed to too much sugar their ability to engulf and disarm bacteria is reduced by 50% and this effect is still evident up to 5 hours after eating the sugar and as a result we have a weakened systemic resistance to all infections. So a sugar intake several times a day will keep the immune system running under par. Remember that sugar comes in many forms, any food listed that ends in OSE is a sugar. It is also worth noting that there is a huge amount of hidden sugar in foods so always read labels carefully. This message would also relate to alcohol intake.


  • Coffee is a diuretic that contributes to the body’s loss of important nutrients such as calcium, magnesium and potassium.


  • Anti-nutrients’ Patrick Holford in his book ‘The Optimum Nutrition Bible’, talks about modern life being full of anti- nutrients. That is things in our environment that rob the body of nutrients or prevent their proper absorption. He lists things like man- made chemicals, smoking and alcohol as the main culprits. These individually can of course be broken down into many different groups. When you consider that there are approximately 50,000 chemicals released into the environment and 400million litres of pesticides and herbicides sprayed onto food and pastures it gives you a feel of the extent of the problem.
    It is almost impossible to avoid all of these, so we can see why it is so important to try and eat a good mixed natural diet to give our immune systems the best support that we can
  • Next week I will look at the other half of the question, what practical things can we do to prepare. I will focus on making the most of the freezer.

Blog originally written by Caroline  September 2014

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