Nutrition: lactose intolerance

Tuesday 08 May 2018


My last 3 blogs have focused on preparation before any cancer treatment begins, focusing on practical things that can be done and prepared in advance. These ideas of course can be used at any time but through my observations and seeing visitors, most are keen to get organised and do something positive to help them to focus and take control.

Now I want to look at a few issues that may arise once treatment has started. This week I want to focus on lactose intolerance. This is something that most people having treatment do not consider and it certainly is not top of most people’s agendas. But I do think that it is important to perhaps consider this because any treatment that involves the digestive system, whether it is chemotherapy, radiotherapy or antibiotics, can throw the body into lactose intolerance.

What is lactose intolerance and how can it affect us?
Lactose is the name of the sugar that is found in milk and dairy products and also appears in some forms in processed foods (see below). In order for us to be able to digest and absorb lactose our bodies produce an enzyme called lactase. Treatment can sometimes inhibit this enzyme from working and we then develop a condition called lactose intolerance.

Lactose intolerance usually manifests as diarrhoea, gas (wind), bloating and stomach cramps. These symptoms can of course be as a result of other things but if you do suffer from any of them then it may be worth considering lactose intolerance.

For example, I have recently met two men who have had radiotherapy in the prostate area and suffered exactly those symptoms. I recommended trying to eliminate dairy from the diet and their symptoms improved enormously. We do of course know that radiotherapy to the bowel area of the body can result in nerve damage and damage to the bowel flora population which would also cause similar problems and not necessarily be linked to lactose problems.

Which foods contain lactose?
So as I have explained lactose appears in dairy foods so these would include milk, milk solids, skim milk powder, cream, buttermilk, malted milk, whey lactose, curds, margarine (unless stated dairy free), dry milk solids, non-fat dairy milk, yogurts, butter and fromage frais. So you can see it is quite an extensive list. Also lactose is hidden in a lot of foods including bread, soups, baked products and cereals so it is worth reading labels.

But what about calcium?
Many people worry about not having dairy foods in their diet because they feel that they will be missing out on the mineral calcium which is one of the minerals needed for strong bones. This should not be an issue because as you know I do not encourage dairy in the diet anyway simply because it does carry with it a growth factor and can be contaminated with hormones and antibiotics given to the cow.

Other foods that are high in very easily absorbed calcium are: broccoli and all dark green leafy vegetables, sardines, tinned salmon, oats, almonds, brazil nuts, quinoa, and beans. So a good variety. Also remember that for calcium to be absorbed it needs to have vitamin D present which we get mainly from the sunshine but it is also found in oily types of fish like tinned salmon and tinned sardines, and egg yolks and fortified breakfast cereals. There are very small amounts of vitamin D in leafy vegetables so if you do eat plenty of these even the small amount will be significant.

When considering calcium it is also worth remembering that some things can actually deplete calcium from the bones.  Any carbonated drinks will contain phosphoric acid and because of the acid content the body will draw calcium from the bones to neutralize the acid in the bloodstream as a result of the drink. Having too much salt in the diet will have much the same effect and so will too much alcohol.

As you all know I am a huge fan of dark green leafy vegetables anyway not only because they are a rich source of calcium.

So going back to the lactose intolerance, generally speaking once the bowel has healed properly and recovered from treatment the body starts to produce lactase again. However as I have explained, dairy foods are not necessarily a food that is essential to include in the diet so I would not be overly concerned if they were eliminated for good or at least kept to a minimum.

I wonder whether anyone reading this blog has found that after removing dairy from the diet their symptoms have improved? This is an interesting concept and such a simple action can have quite profound results.

Blog originally written by Caroline October 2014 - checked April 2020

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