Atherosclerosis in Ancient Mummies Revisited

Many of you are already aware of the recent study that examined atherosclerosis in 137 ancient mummies from four different cultures (1). Investigators used computed tomography (CT; a form of X-ray) to examine artery calcification in mummies from ancient Egypt, Peru, Puebloans, and arctic Unangan hunter-gatherers. Artery calcification is the accumulation of calcium in the vessel wall, and it is a marker of severe atherosclerosis. Where there is calcification, the artery wall is thickened and extensively damaged. Not surprisingly, this is a risk factor for heart attack. Pockets of calcification are typical as people age.

I'm not going to re-hash the paper in detail because that has been done elsewhere. However, I do want to make a few key points about the study and its interpretation. First, all groups had atherosclerosis to a similar degree, and it increased with advancing age. This suggests that atherosclerosis may be part of the human condition, and not a modern disease. Although it's interesting to have this confirmed in ancient mummies, we already knew this from cardiac autopsy data in a variety of non-industrial cultures (2, 3, 4, 5).

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Extreme Flu Activity in the US

A friend of mine came down with a nasty flu recently. I checked Google Flu Trends, and found that flu activity is currently at "intense" levels throughout the US. This is the highest flu activity Google Flu Trends has recorded in the last six years (image from Google Flu Trends 1/3/12).

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Nutrition Science Initiative (NuSI)

Some of you may have heard of an ambitious new nutrition research foundation called the Nutrition Science Initiative (NuSI). In this post, I'll explain what it is, why it matters, and how I feel about it-- from the perspective of an obesity researcher.

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Calories and Carbohydrate: a Natural Experiment

In the lab, we work hard to design experiments that help us understand the natural world. But sometimes, nature sets up experiments for us, and all we have to do is collect the data. These are called "natural experiments", and they have led to profound insights in every field of science. For example, Alzheimer's disease is usually not considered a genetic disorder. However, researchers have identified rare cases where AD is inherited in a simple genetic manner. By identifying the genes involved, and what they do, we were able to increase our understanding of the molecular mechanisms of the disease.

The natural experiment I'll be discussing today began in 1989 with the onset of a major economic crisis in Cuba. This coincided with the loss of the Soviet Union as a trading partner, resulting in a massive economic collapse over the next six years, which gradually recovered by 2000.

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New Review Paper by Yours Truly: High-Fat Dairy, Obesity, Metabolic Health and Cardiovascular Disease

My colleagues Drs. Mario Kratz, Ton Baars, and I just published a paper in the European Journal of Nutrition titled "The Relationship Between High-Fat Dairy Consumption and Obesity, Cardiovascular, and Metabolic Disease". Mario is a nutrition researcher at the Fred Hutchinson Cancer Research Center here in Seattle, and friend of mine. He's doing some very interesting research on nutrition and health (with an interest in ancestral diets), and I'm confident that we'll be getting some major insights from his research group in the near future. Mario specializes in tightly controlled human feeding trials. Ton is an agricultural scientist at the University of Kassel in Germany, who specializes in the effect of animal husbandry practices (e.g., grass vs. grain feeding) on the nutritional composition of dairy. None of us have any connection to the dairy industry or any other conflicts of interest.

The paper is organized into three sections:

1. A comprehensive review of the observational studies that have examined the relationship between high-fat dairy and/or dairy fat consumption and obesity, metabolic health, diabetes, and cardiovascular disease.
2. A discussion of the possible mechanisms that could underlie the observational findings.
3. Differences between pasture-fed and conventional dairy, and the potential health implications of these differences.

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What Causes Type 2 Diabetes, and How Can it be Prevented?

In the comments of the last post, we've been discussing the relationship between body fatness and diabetes risk. I think this is really worth understanding, because type 2 diabetes is one of the few lifestyle disorders where 1) the basic causes are fairly well understood, and 2) we have effective diet/lifestyle prevention strategies that have been clearly supported by multiple controlled trials.

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Interview with Aitor Calero of Directo al Paladar

Aitor Calero writes for the popular Spanish cooking and nutrition blog, Directo al Paladar ("straight to the palate"). We did a written interview a while back, and he agreed to let me post the English version on my blog. The Spanish version is here and here.

Without further ado, here it is:

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Lessons From Ötzi, the Tyrolean Ice Man. Part II

Otzi's Diet

Otzi's digestive tract contains the remains of three meals. They were composed of cooked grains (wheat bread and wheat grains), meat, roots, fruit and seeds (1, 2). The meat came from three different animals-- chamois, red deer and ibex. The "wheat" was actually not what we would think of as modern wheat, but an ancestral variety called einkorn.

Isotope analysis indicates that Otzi's habitual diet was primarily centered around plant foods, likely heavily dependent on grains but also incorporating a variety of other plants (3). He died in the spring with a belly full of einkorn wheat. Since wheat is harvested in the fall, this suggests that his culture stored grain and was dependent on it for most if not all of the year. However, he also clearly ate meat and used leather made from his prey. Researchers are still debating the quantity of meat in his diet, but it was probably secondary to grains and other plant foods. It isn't known whether or not he consumed dairy.

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Lessons From Ötzi, the Tyrolean Ice Man. Part I

This is Otzi, or at least a reconstruction of what he might have looked like. 5,300 years ago, he laid down on a glacier near the border between modern-day Italy and Austria, under unpleasant circumstances. He was quickly frozen into the glacier. In 1991, his slumber was rudely interrupted by two German tourists, which eventually landed him in the South Tyrol Museum of Archaeology in Italy.

Otzi is Europe's oldest natural human mummy, and as such, he's an important window into the history of the human species in Europe. His genome has been sequenced, and it offers us clues about the genetic history of modern Europeans.

Otzi's Story

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