03 August 2012


Today, statistically half of us will get cancer. This proportion has increased over the last few decades from 1 in 3. The increase is most striking in civilized countries.

My questions are:

1. What is the reason that cancer rates are still increasing? If diet is not relevant, what else can be the cause? Pollution? Genes?

2. If diet is really not that relevant, why doctors are recommending more and more, to reduce consumption of sugar especially? Here, I will write more about cancer research.

1. Incidence of cancer in traditional populations

Traditional populations had a very low incidence of cancer. Something changed in our environment which causes epidemic proportions of chronic diseases.

- The famous medical missionary, Dr. Albert Schweitzer, writing in Berglas [1957], reports the following [Berglas 1957, preface]:
"On my arrival in Gabon, in 1913, I was astonished to encounter no cases of cancer. I saw none among the natives two hundred miles from the coast. I can not, of course, say positively there was no cancer at all, but, like other frontier doctors, I can only say that if any cases existed they must have been quite rare."

- Williams [1908] reports that cancer is extremely rare among Australian aborigines and in the aboriginal peoples of Africa and also North America. (Note the date of the citation: 1908, a time when there were far more hunter-gatherers than there are today.)

- Stefansson [1960] describes the search of George B. Leavitt, a physician on a whaling ship, who searched for cancer among the Inuit of Canada and Alaska. It took him 49 years, from 1884 to the first confirmed case in 1933, to find cancer. (Stefansson [1960] describes a possible but unconfirmed case of cancer in 1900, and Eaton et al. [1988] describe cancer in a 500-year-old Inuit mummy.)

- Schaefer [1981] reports that breast cancer was virtually unknown among the Inuit in earlier times, but was one of the most common forms of malignancy by 1976.

Migration studies show that when part of the population moves to a different area, the cancer incidence pattern in these newly settled populations reflects the incidence pattern of that area and not the incidence pattern of their original country. This means that genetics are not a determining factor in the risk of developing cancer. It has more to do with lifestyle.

Is the consumption of saturated fat to blame for our chronic diseases? If saturated fat is harmful, these observations do not support that theory (it's actually the opposite):

- For instance, the Russians of the Caucasus mountains live to great ages on a diet of fatty pork and whole raw milk products. Or, the Hunzas, also known for their robust health and longevity, eat substantial portions of goat's milk which has a higher saturated fat content than cow's milk (86). In contrast, the largely vegetarian Hindus of southern India have the shortest life-spans in the world, partly because of a lack of food, but also because of a distinct lack of animal protein in their diets. H. Leon Abrams’ comments are instructive here:
"Vegetarians often maintain that a diet of meat and animal fat leads to a pre-mature death. Anthropological data from primitive societies do not support such contentions."
- With regards to endurance and energy levels, Dr Price traveled around the world in the 1920s and 1930s, investigating native diets. Without exception, he found a strong correlation between diets rich in animal fats, robust health and athletic ability. Special foods for Swiss athletes, for example, included bowls of fresh, raw cream. In Africa, Dr Price discovered that groups whose diets were rich in fatty meats and fish, and organ meats like liver, consistently carried off the prizes in athletic contests, and that meat-eating tribes always dominated tribes whose diets were largely vegetarian.

- Anthropologists/explorers such as Vilhjalmur Stefansson reported that the Innuit and North American Indian tribes would worry when their catches of caribou were too lean: they knew sickness would follow if they did not consume enough fat. In other words, these primitive peoples did not like having to eat lean meat.

Vilhjamur Stefansson

- Northern Canadian Indians would also deliberately hunt older male caribou and elk, for these animals carried a 50-pound slab of back fat on them which the Indians would eat with relish. This “back fat” is highly saturated. Native Americans would also refrain from hunting bison in the springtime (when the animals' fat stores were low, due to scarce food supply during the winter), preferring to hunt, kill and consume them in the fall when they were fattened up.

- Explorer Samuel Hearne, writing in 1768, described how the Native American tribes he came in contact with would selectively hunt caribou just for the fatty parts:
"On the twenty-second of July, we met several strangers, whom we joined in pursuit of the caribou, which were at this time so plentiful that we got everyday a sufficient number for our support, and indeed too frequently killed several merely for the tongues, marrow, and fat."
After decades of research, the ACS (American Cancer Society) was acknowledging that "there was little evidence that the total amount of fat consumed increases cancer risk". But, a diet with less fat is still recommended in order to decrease the risk of developing, cancer and to be healthy. This is not supported by epidemiological studies.

Maybe we should see in what environment cancer cells thrive.

2. Cancer Research

In 1981, Richard Doll (Oxford Epidemiologist) and Richard Peto published an analysis in the Journal of the National Cancer Institute. Their observations were:
- Chemicals and food additives play a minimal role in human cancers
- Diet played the largest role

In the late 1970s John Yudkin had noted that the 5 nations with the highest breast cancer mortality (in descending order) are:
- UK
- Netherlands
- Ireland
- Denmark
- Canada

These countries had the highest sugar consumption (in descending order):
- UK
- Netherlands
- Ireland
- Canada
- Denmark

The lowest mortality from breast cancer:
- Japan
- Yugoslavia
- Portugal
- Spain
- Italy

and the lowest sugar consumption:
- Japan
- Portugal
- Spain
- Yugoslavia
- Italy

Scientists had found that sugar intake is "positively correlated with both the incidence and mortality from: colon, rectal, breast, ovarian, prostate, kidney, nervous system and testicular cancers." These are some of the studies about the link of cancer and sugar consumption.

Over the years, one common observation was that women with Type 2 diabetes or glucose intolerance have a higher-than-average incidence of breast cancer and most of the cancer patients are glucose intolerant.

What really happens at a cellular level?

A bit of history:
- The Nobel Prize winner Otto Warburg discovered in the 1920s, that cancer cells survive without oxygen. They need sugar to multiply (by fermentation rather than respiration.
- In the 1960s, researchers reported that insulin promotes growth in healthy and malignant tissue as well.
- Howard Temin (Nobel Prize) reports that insulin added to the serum (blood plasma) results in tumor growth.
- Kent Osborne (National Cancer Institute) says that one line of particularly aggressive breast-cancer cells were "exquisitely sensitive to insulin".
- In the 1970s researchers had reported that malignant breast tumors had more receptors for insulin that did healthy tissue. This means that cancer cells have a "selective growth advantage" over healthy cells. In the presence of insulin, cancer cells will grow faster that healthy cells.

About the cells:
We constantly replicate our cells. These new cells usually are not as perfect as the previous ones (this is called ageing). Some changes in the DNA can cause the cell to become cancerous and start to multiply. However, cells have a built in mechanism to search out defects in the newly replicated DNA and repair it or prompting it to commit "suicide". If this mechanism is disabled, the damaged cells start to proliferate. This is called a tumor.

What scientist discovered is that IGF (Insulin-like growth factor plays also a very important role in cell growth). IGF is similar in structure to insulin and can mimic its effects. Cancer cells have 2 to 3 times more IGF receptors on their surface than normal cells. So here again: an advantage for growth. If the cancer cell is in an insulin and IGF rich environment, this cell will multiply very easily. (Science is a bit more complicated here. I won't go into details.)

Renato Baserga (Thomas Jefferson University) discovered that by shutting down the IGF receptors on cancer cells, the cells will not grow, they will starve, especially metastasized tumor cells).

"Malignancy requires chronically high levels of insulin and IGF induced by modern diets. This hypothesis is supported by epidemiological studies linking hyperinsulinemia and elevated levels of IGF to an increased risk of breast, prostate, colorectal, and endometrial cancers." - Gary Taubes 

Bottom line:
A diet high in sugar and refined carbohydrates is the cause of chronically elevated insulin and IGF level. This environment is beneficial for cancer cell growth. The best we can do to starve these malignant cells, is to lower our sugar and carbohydrate intake to a minimum. Fat has no effect on insulin. Even protein (lean meat) has some effect on insulin levels! So, it is possible to starve cells on a high fat and low carbohydrate diet.

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