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Does sugar feed cancer?

Should I totally avoid sugar if I have Cancer?

No!!

This is one of the most commonly asked questions and many people I have met will have tried to cut sugar out of their diet. However, what needs to be understood is that sugar is a type of carbohydrate. Carbohydrates are an important energy food and every cell in the body requires glucose or sugar to function. For example the brain wholely and solely uses glucose or sugar to keep it functioning. A drop in blood sugar can cause feelings of fatigue, dizziness and faintness.

When you eat any kind of carbohydrate (found in desserts, sweetened drinks, fruits, milk, grains and starchy vegetables), the body breaks the carbohydrates down in to a range of simple sugars, which are then converted into glucose to be taken into the cells. Therefore, the idea that sugar per se somehow ‘feeds’ cancer is neither useful nor correct – sugar, is another form of carbohydrate, therefore feeds every cell in our bodies.

However what is important to understand is that there are different types or quality grades of carbohydrate foods. There are the wholesome grain type foods, fruits, vegetables and dairy foods which can move more slowly (slow or low GI type carbohydrates) and then there are those which are more processed, mixed with with higher calorie, higher fat snack food type ingredients and typically these ones are absorbed quite quickly (high GI or fast release types).

When our diet includes more of the fast release or high GI types (refined or more processed carbohydrate foods) this requires the body to produce more of the hormone insulin. Insulin is needed to enable the cells to take up glucose from our blood into the muscle cells. However, several spikes of insulin across the day could be a risk factor for cancer as well as weight gain. (Insulin is a growth hormone and promotes fat storage). The slower release carbohydrate foods (grains, dairy, colder weather fruits and vegetables) means these foods are absorbed and used in the body over 2-3 hours. These foods do not require such a fast, rapid insulin response (lower levels) as the slower release means that the blood sugar levels do not spike at such a high level. The body is always working to keep our blood sugar levels within a normal ideal range. A rapid rise in blood sugar means the body responds in a panic and produces larger amounts of insulin. A gradual and more level rise in the blood sugar enables the body to have more time to process the sugar and it doesn’t result in excessive amounts of insulin floating around the body.

For an all-round balanced diet, it is best to get your energy needs met by a range of lower GI carbohydrates such as vegetables, fruit, whole grains, and legumes (beans). However at the same time there is no need to become fanatical about this – sugar is not like some kind of deadly poison. If you fancy a little bit of luxury chocolate, or a slice of delicious home-baked carrot cake, have it. Gosh, you are in treatment for cancer and you should also enjoy your food.

One other point to bear in mind is that you can’t always judge your carbohydrate needs in cancer by your normal carbohydrate needs. This is a complex area, and one where the individual component in cancer cases must be borne in mind. Many people find that the toll of the illness, and the impact the treatments have on the body, compromise its nutrient stores. Due to the extra load caused by the cancer growing in the body, the treatment side effects, and sometimes a wasting effect (cachexia), there may be a need for extra calories and some extra carbohydrate foods can help out here. So, when considering your overall carbohydrate intake, again do discuss your individual needs with your doctor or dietitian if necessary.