Sabtu, 26 Juli 2008

The Inuit: Lessons from the Arctic

The Inuit (also called Eskimo) are a group of hunter-gatherer cultures who inhabit the arctic regions of Alaska, Canada and Greenland. They are a true testament to the toughness, adaptability and ingenuity of the human species. Their unique lifestyle has a lot of information to offer us about the boundaries of the human ecological niche. Weston Price was fascinated by their excellent teeth, good nature and overall robust health. Here's an excerpt...

Senin, 21 Juli 2008

Book Review: "The Human Diet: Its Origins and Evolution"

I recently read this book after discovering it on another health site. It's a compilation of chapters written by several researchers in the fields of comparative biology, paleontology, archaeology and zoology. It's sometimes used as a textbook. I've learned some interesting things, but overall it was pretty disappointing. The format is disjointed, with no logical flow between chapters. I also would not call it comprehensive, which is one of...

Rabu, 16 Juli 2008

Sunscreen and Melanoma

Melanoma is the most deadly type of skin cancer, accounting for most skin cancer deaths in the US. As Ross pointed out in the comments section of the last post, there is an association between severe sunburn at a young age and later development of melanoma. Darker-skinned people are also more resistant to melanoma. The association isn't complete, however, since melanoma sometimes occurs on the soles of the feet and even in the intestine. This may be due to the fact that there are several types of melanoma, potentially with different causes....

Senin, 14 Juli 2008

Melanoma and Sunblock

A report came out recently showing that melanoma incidence has increased dramatically in the US since 1973, particularly among women. The authors suggested the rise could be due to increasing sun exposure, which I am highly skeptical of. The data he cites to support that idea are quite weak. I think the prevalence of vitamin D deficiency in this country suggests otherwise.Melanoma is the most deadly form of skin cancer, and the only type that is commonly life-threatening. Its link to sun exposure is tenuous at best. For example, it often occurs...

Kamis, 10 Juli 2008

Grains and Human Evolution

You've heard me say that I believe grains aren't an ideal food for humans. Part of the reason rests on the assertion that we have not been eating grains for long enough to have adapted to them. In this post, I'll go over what I know about the human diet before and after agriculture, and the timeline of our shift to a grain-based diet. I'm not an archaeologist so I won't claim that all these numbers are exact, but I think they are close enough to make my point. As hunter-gatherers, we ate some combination of the following: land mammals (including...

Rabu, 09 Juli 2008

Another China Tidbit

A final note about the Chinese study in the previous post: the overweight vegetable-eaters (read: wheat eaters) exercised more than their non-vegetable-eating, thin neighbors. So although their average calorie intake was a bit higher, their expenditure was as well. Although I speculated in the last post that affluent people might be eating more wheat and fresh vegetables, the data don't support that. Participants with the highest income level actually adhered to the wheat and vegetable-rich pattern the least, while low-income participants...

Selasa, 08 Juli 2008

Wheat in China

Dr. Michael Eades linked to an interesting study yesterday on his Health and Nutrition blog. It's entitled "Vegetable-Rich Food Pattern is Related to Obesity in China." It's one of these epidemiological studies where they try to divide subjects into different categories of eating patterns and see how health problems associate with each one. They identified four patterns: the 'macho' diet high in meat and alcohol; the 'traditional' diet high in rice and vegetables; the 'sweet tooth' pattern high in cake, dairy and various drinks; and the 'vegetable...

Senin, 07 Juli 2008

Cancer in Other Non-Industrialized Cultures

In Cancer, Disease of Civilization (1960), Wilhjalmur Stefansson mentions a few cultures besides the Inuit in which large-scale searches never turned up cancer. Dr. Albert Schweitzer examined over 10,000 traditionally-living natives in Gabon (West Africa) in 1913 and did not find cancer. Later, it became common in the same population as they began "living more and more after the manner of the whites." In Cancer, its Nature, Cause and Cure (1957), Dr. Alexander Berglas describes the search for cancer among natives in Brazil and Ecuador by Dr....

Sabtu, 05 Juli 2008

Mortality and Lifespan of the Inuit

One of the classic counter-arguments that's used to discredit accounts of healthy hunter-gatherers is the fallacy that they were short-lived, and thus did not have time to develop diseases of old age like cancer. While the life expectancy of hunter-gatherers was not as high as ours today, most groups had a significant number of elderly individuals, who sometimes lived to 80 years and beyond. Mortality came mostly from accidents, warfare and infectious...

Jumat, 04 Juli 2008

Cancer Among the Inuit

I remember coming across a table in the book Eat, Drink and Be Healthy (by Dr. Walter Willett) a few years back. Included were data taken from Dr. Ancel Keys' "Seven Countries Study". It showed the cancer rates for three industrialized nations: the US, Greece and Japan. Although specific cancers differed, the overall rate was remarkably similar for all three: about 90 cancers per 100,000 people per year. Life expectancy was also similar, with...

Kamis, 03 Juli 2008

Cancer and the Immune System

My understanding of cancer has changed radically over the past few months. I used to think of it as an inevitable consequence of aging, a stochastic certainty. The human body is made of about 50 trillion cells, many of which replicate their DNA and divide regularly. It's only a matter of time until one of those cells randomly accumulates the wrong set of mutations, and loses the molecular brakes that restrict uncontrolled growth. Strictly speaking, the idea is correct. That is how cancer begins. However, there's another check in place that operates...