Sunday 18 May 2014

Cancer: The Seed and Soil Hypothesis

Cancer is a difficult disease to understand because science makes it so complex. However, there are ways to describe the development of cancer that do not require a PhD in oncology. It was the surgeon Stephen Paget who first described the development of cancer as analogous to that of a growing weed. Weeds are defined in horticulture as plants that encroach upon and inhibit the growth of other plants. If we consider weeds to be cancer cells and the other plants to be normal healthy cells the analogy is in fact brilliant.

Initiation

Initiation is the first stage in the development of cancer. In this process a normal cell will lose the requirement to divide only a limited number of times, and so will become immortal. In addition, the normal apoptotic regulatory mechanisms that programme cell death are inhibited. Initiation is analogous to a seed landing in the soil. At this point there is no real problem as the weed is small and not fully formed, and may even go unnoticed. However, the weed in genetically programmed to invade the space of other plants just as a cancer cell is programmed to invade other tissues.

Promoton

As the weed receives the nutrients it requires, it begins to grow and invade other parts of the garden. In the same way a cancer cell can only grow if it receives the nutrient it requires. In the case of cancer, new blood vessels must be formed to allow the cancer cells to divide and spread. This is accomplished by the release of growth factors that trigger the creation of new blood vessels to bring nutrients (angiogenesis). At the same time inflammation is created by the cancer cells to increase the susceptibility of the healthy tissue for invasion. Weeds use a similar strategy of rapid growth to out compete other plants for nutrients.

Progression

The final stage of cancer is the progression of cancer to other parts of the body (metastasis). This is akin to a weed producing seeds and spreading throughout the garden. However, unlike weeds, the original tumour will secrete substances that inhibit the growth of other tumours, leaving them at the micro tumour stage. This explains why once the original tumour is often surgically removed, other tumours rapidly form (because the inhibitors are removed from circulation). However, irrespective of this slight nuance, promotion ultimately results in the spread of cancer.

Effective Treatments

Once a cancer has reached the late stages it is very difficult to do anything to stop a rapid decline in health. However, catching a cancer in the initiation and promotion stages can be successful in preventing cancer. This is demonstrated by the statistics that show that Asians are just as likely to develop cancer as people in the West. However, the tumours in Asians often do not develop beyond the micro tumour stage and so the rates of cancer mortality are much lower. Something in the diet of the Asian men and women is protecting them for cancer.

Diet

The protection afforded to Asians comes from their diet. This is proven by the rise in cancer mortality of Asian men and women who adopt the Western diet. The Western diet is low in the substances found in more traditional diets that are protective of cancer. Those factors are plant phytochemicals such as found in soy, turmeric, ginger, cruciferous vegetables, garlic, onions, tomatoes, mushrooms, green tea and red wine. In the case of Asian men and women, soy protects them from the promotion of micro tumours beyond the initiation stage of cancer.

Why is Nutrition Effective?

Nutrition is particularly effective at inhibiting the initiation and promotion of cancer because the substances in plants work in multiple ways. Some phytochemicals increase detoxification which reduces the risk of carcinogens forming cancer cells in the body. Some inhibit inflammation that is required for the spread of cancer. Some inhibit the formation of the blood vessels required by cancer cells to grow. Some boost the immune system allowing direct killing of cancer cells. Eating a mixed diet therefore provides multiple mechanisms to protect from cancer.

Synergism

The real benefits with the nutritional approach to cancer prevention therefore, is that the nutrients are known to act synergistically. Addition of a wide range of plant phytochemicals increases the anti-cancer effect significantly higher than would be expected by the sum of the individuals parts. For this to happen a wide variety of anti-cancer foods must be eaten regularly, allowing them to be in the tissues continuously to guard against the development of cancer. This means abandoning the Western diet and incorporating traditional diet patterns into daily life.

How To Kill A Weed

If we go back to the analogy of a weed, we can see the effectiveness of nutrition. Some nutrients tend the garden removing the seeds before the weeds can grow (detoxification). Some nutrients attack the roots of the weeds once they grow (inhibitors of angiogenesis). Some nutrients pluck the flower heads from the weeds before the seeds can spread (immune booster). And some weeds prepare the ground so that new seeds cannot germinate (anti-inflammatories). No weed could grow in a garden tended by such diligent gardening, and in the same way nutrition makes it incredibly hard for cancer to take root in the body.
RdB

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