Posted by Rose after help from Pete

Living with cancer – 3: Cancer promoters in dietary foods

Most of us in the UK have a diet that is more and more unhealthy compared to that of our grandparents. This is due to:

• Depletion of agricultural soils reducing vitamins and minerals in our plant foods.
• The rise of agri-business with the increased usage of fertilisers, pesticides, and mono-culture crops, plus the recent introduction of Genetically Modified (GM) foods.
• Intensive animal husbandry using rapid growth-promoting hormones, and superfoods.
• The industrialisation of food processing to produce cheap and tasty 'fast food', ready meals, and luxury foods with long shelf life.

These notes are particularly concerned with cancer-promoting foods, however many other unhealthy medical conditions are also promoted by these phenomena. Key cancer-promoting foods will be discussed, with some tips on alternatives.

1. Foods that rapidly supply glucose to the blood 

Glucose is the main food cancer cells need to grow and divide – the more this is available the faster tumours grow. High levels of glucose also demand high levels of insulin production, which stimulates cell growth, and acts as a fertiliser for tumours. There is also a link between blood glucose levels and cancer-promoting inflammation. The following are worth minimising for cancer prevention, and worth cutting out completely when active cancer tumours are present: refined white and brown sugars, honey, fruit juices, and processed foods containing sugar, honey, glucose or fructose, and corn syrup, which contains glucose + fructose.

Fruit sugars like fructose are fine in whole fruits because digestion is slowed down by the fibre and complex carbohydrates present. Fruit juice, however, concentrates the fructose and it enters the blood rapidly. Refined and finely divided carbohydrates, like white and brown flours, white rice, and pasta, also rapidly enter the blood as glucose. The dietary solution for these problems is to switch to whole foods with a high content of fibre and complex carbohydrates, and to use the Glycemic Index (GI) to put together food combinations with slow average rates of digestion.

GI measures blood glucose one and a half hours after food consumption. Refined sugar glucose is given a GI of 100, and other foods are given GIs that show what percentage of the refined sugar glucose they provide. Healthy foods have low GIs, and unhealthy foods have high GIs. The good news is that mixing low GI foods with medium or even high GI foods, will reduce the overall GI. Low GI foods are wholefoods with high fibre and complex carbohydrate content that take a long time to digest.

Healthy eating suggestions:
Whole grains like brown basmati rice, oats and barley. Home-made muesli. Nuts.

Pulses like peas, beans, and lentils. Wholemeal bread with seeds or multigrains.

Root vegetables of all kinds – the more variety the better. A variety of fresh fruit.

Use sweeteners like stevia or xylitol, and dried fruit or carrots for occasional low GI cakes.
Aspartame, found in more than 5000 food and drink items from diet drinks to low fat yoghurts, may be best avoided. Research has linked daily diet soda drink containing aspartame to a greater risk of leukemia, lymphoma, and multiple myeloma in humans (Cancer Watch 2012).

2. Foods that supply high sodium levels to the blood

We ingest sodium from a wide variety of foods, as refined table salt (sodium chloride), as a preservative in smoked and dried meat and fish, as taste enhancing salt in monosodium glutamate, refined foods like cereals, snack food, ready meals, and even beer and fizzy soft drinks. Excess sodium upsets cellular membranes throughout the body, interfering with the sodium/potassium balance in the cells, and making the normal metabolic processes in the cells inefficient. The cellular environments increase in acidity, which has debilitating effects on the water balance of the body, and can cause stress and fatigue. The acidity favours the growth of cancer cells. Growing cancer cells excrete acid waste products adding to the acidity. A recommended maximum for salt is 5 grams per day, but there is mounting evidence that a lower level would be healthier.

Increasing the intake of potassium-rich foods can help redress the sodium/potassium balance, but is insufficient without cutting down on the foods that supply sodium. A healthy body works best when slightly alkaline. This nutritional arena has given rise to talking about acid or alkaline bodies, which can be measured by taking the pH of the saliva. Acid bodies increase metastasising cells, and provide them favourable environments for settling elsewhere in the body. To return to a more alkaline state take a teaspoon of sodium bicarbonate in a glass of warm water, first thing in the morning or last thing at night.

When sodium nitrate is used as a preservative, nitrate enhances the cancer-promoting potential of the combination. Research shows that 20% of ingested nitrate is transformed in the body to nitrite and N-nitroso compounds, potentially causing cancers such as colon, bladder, and oesophageal cancers, especially when vitamin C levels are low. Sodium nitrate and sodium nitrite are preservatives used in dried meats, bacon, pepperoni, sausages, hams and hot dogs.

3. Foods high in omega-6 fatty acids

Omega-6 and omega-3 (plus a small amount of omega-9) essential fatty acids are not made in the body, so need to be supplied in the food we eat. The healthy ratio of omega-6 to omega-3 fatty acids is about 1 : 1. The demand for cheap palatable food has encouraged farming practices that vastly increase the yields of desired foods like red meat, dairy products and eggs. One way this is done is providing high calorie foods. Cows can be fed on corn (maize), soy, and wheat rather than grass; chickens can be fed on fed on corn. When high calorie foods are given to animals the omega-6 to omega-3 ratio rises in proportion with the non-grass part of the feed. Omega 6 fatty acids encourage inflammation, coagulation and stimulation of cell growth. Omega 3 fatty acids regulate inflammation, fluidisation of blood, and regulate cell growth. As ratios of omega-6 to omega-3 in foods rise, so does the potential for cancers.

Another practice that increases yields is the use of growth hormones, some of which promote cancers. In particular, bovine growth hormone is associated with hormonal cancers such as breast, prostate and ovarian cancer. This hormone is banned in the EU and Canada, but not in the USA. Processed foods from parts of the world outside the EU are highly likely to contain this hormone, derived from the use of milk products from the USA.

Healthy dietary changes are to reduce red meat, particularly beef, eating small amounts of organic beef from grass fed cows; going dairy free; and eating organic chickens, fed with forage rather than grain, and organic eggs from forage fed chickens. Omega-3 supplements appear to be very worthwhile.

4. Unhealthy fats can encourage cancers

Different types of fats differ a great deal in how healthy they are. The chief types are trans fats, saturated fats, polyunsaturated fats, monounsaturated fats and cholesterol.

Trans fats (hydrogenated or partially hydrogenated fats) have been shown by research to be the least healthy of the typical fats in our current diets. The end products of digestion of trans fats are free radicals. The more free radicals at large in the body the greater the risk of cancer. Several research studies have shown that trans fats increase tissue inflammation in the body, through their stimulus of prostaglandins. Such inflammation increases risks of many chronic diseases from heart disease to cancer. Transfats have been linked to higher levels of colon cancer and to pancreatic cancer.

In the USA in 2013, the FDA announced that 'trans fats are not generally recognised as safe for use in food.' This was backed by Harvard School of Public Health saying there was massive scientific evidence to support this position. In a recent study of 80,000 nurses, the Mayo Clinic showed that women whose diets were high in both saturated and trans fats had an increased risk of heart attack, with those consuming considerable amounts of trans fats higher heart attack risks than nurses who ate a lot of saturated fat.” The Mayo Report continued. “In fact, trans fat maybe even more damaging because in addition to raising your bad cholesterol level, it also appears to lower your 'good' cholesterol level.”

Many products in the USA are labelled 'Trans Fat Free'. In Europe there is no general ban on trans fats, though bans exist in some EU member countries. In the UK the coalition government suggested that food retailers could omit trans fats voluntarily, and many supermarkets and large food retailers have done so, or are in process of doing so. However, this does mean there is a need to check the presence or absence of trans fats in processed food.

Saturated fats have been regarded as bad for many years as they are known to increase inflammation in the body. However, in 2013 the British Medical Journal ran a piece that concluded that saturated fat was not the cause of heart disease. The authors claimed the scientific advice that saturated fat must be removed to reduce the risk of cardiovascular disease 'has, paradoxically, INCREASED our cardiovascular risks'. It appears that it is 'Pattern B type' saturated fat, linked to bad cholesterol, which is mainly derived from trans fats, that is at fault. It does seem a good idea to minimise saturated fat.

Polyunsaturated fats are liquid at room temperature and are essential because the body can't make them. Many margarines contain polyunsaturated fats, but because of the refining processes are no longer healthy fats, particularly when used for cooking. Polyunsaturated oils should provide around 2% of daily calories.

Monounsaturated oils are the healthiest, particularly cold pressed oils. They are better for cooking as they have a high oxidation threshold and remain stable on heating so do not easily become hydrogenated or saturated. Olive oil has the highest percentage of monounsaturated oil at 73%, with rapeseed oil the next down to 60%. Olive oil also has the added benefits of containing polyphenols that have anti-cancer properties. It is still useful to limit the cooking temperature of olive oil, and the recommended method is 'sweating' rather than stir-frying.