Sunday, April 29, 2012
Aging skin bruising
It is not uncommon for a friend or relative to corner me with a worried look on his face and ask me about bruising on the arms or legs. It is one of the more common concerns of patients in the office too. People are worried that it is a harbinger of leukemia or some other blood disorder. "Look at my skin. These spots just appear for no reason. What are they?"
What I'm seeing is the
Saturday, April 28, 2012
Beyond Ötzi: European Evolutionary History and its Relevance to Diet. Part I
In the previous post, I explained that Otzi descended in large part from early adopters of agriculture in the Middle East or nearby. What I'll explain in further posts is that Otzi was not a genetic anomaly: he was part of a wave of agricultural migrants that washed over Europe thousands of years ago, spreading their genes throughout. Not only that, Otzi represents a halfway point in the evolutionary process that transformed Paleolithic humans into modern humans.
Did Agriculture in Europe Spread by Cultural Transmission or by Population Replacement?
There's a long-standing debate in the anthropology community over how agriculture spread throughout Europe. One camp proposes that agriculture spread by a cultural route, and that European hunter-gatherers simply settled down and began planting grains. The other camp suggests that European hunter-gatherers were replaced (totally or partially) by waves of agriculturalist immigrants from the Middle East that were culturally and genetically better adapted to the agricultural diet and lifestyle. These are two extreme positions, and I think almost everyone would agree at this point that the truth lies somewhere in between: modern Europeans are a mix of genetic lineages, some of which originate from the earliest Middle Eastern agriculturalists who expanded into Europe, and some of which originate from indigenous hunter-gatherer groups including a small contribution from neanderthals. We know that modern-day Europeans are not simply Paleolithic mammoth eaters who reluctantly settled down and began farming.
Read more »
Did Agriculture in Europe Spread by Cultural Transmission or by Population Replacement?
There's a long-standing debate in the anthropology community over how agriculture spread throughout Europe. One camp proposes that agriculture spread by a cultural route, and that European hunter-gatherers simply settled down and began planting grains. The other camp suggests that European hunter-gatherers were replaced (totally or partially) by waves of agriculturalist immigrants from the Middle East that were culturally and genetically better adapted to the agricultural diet and lifestyle. These are two extreme positions, and I think almost everyone would agree at this point that the truth lies somewhere in between: modern Europeans are a mix of genetic lineages, some of which originate from the earliest Middle Eastern agriculturalists who expanded into Europe, and some of which originate from indigenous hunter-gatherer groups including a small contribution from neanderthals. We know that modern-day Europeans are not simply Paleolithic mammoth eaters who reluctantly settled down and began farming.
Read more »
Wednesday, April 25, 2012
Tuesday, April 24, 2012
Lessons From Ötzi, the Tyrolean Ice Man. Part III
There are two reasons why I chose this time to write about Otzi. The first is that I've been looking for a good excuse to revisit human evolutionary history, particularly that of Europeans, and what it does and doesn't tell us about the "optimal" human diet. The second is that Otzi's full genome was sequenced and described in a recent issue of Nature Communications (1). A "genome" is the full complement of genes an organism carries. So what that means is that researchers have sequenced almost all of his genes.
Read more »
Read more »
Sunday, April 22, 2012
The Dangerous Choking Game
There is a game that pre-teens are playing that has killed 82 kids since 1995, according the the Centers for Disease Control (CDC). It is called the "choking game" and these youngsters have no idea how dangerous it is. There are probably thousands of choking deaths all across the country that have not been reported to the CDC and countless parents who think their child committed suicide,
Tuesday, April 17, 2012
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.
Read more »
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.
Read more »
Hidden Health Care Pricing and Costs
More and more employed people who have health insurance are facing large deductibles so they are actually paying "out of pocket" for tests, Xrays and doctor visits. Health care policy-makers talk about involving the consumer in the cost of care as a way to force competition and hold down prices. But finding out how much something costs can be a herculean effort and take hours of time
Monday, April 16, 2012
Red Meat Linked to Death
Advanced warning: meat lovers are not going to like this.
A well done study published in the Archives of Internal Medicine as shown that red meat consumption is linked with an increased risk of total death, cardiovascular death and cancer death. Yup...death! That goes further than what we knew before about red meat connection to heart attacks and strokes. This is the big one.
This study
Exercise and Food Intake
The New York Times just published an article reviewing some of the recent research on exercise, food intake and food reward, titled "Does Exercise Make You Overeat?". I was planning to write about this at some point, but I don't know when I'd be able to get around to it, and the NYT article is a fair treatment of the subject, so I'll just point you to the article.
Basically, burning calories through exercise causes some people to eat more, but not everyone does, and a few people actually eat less. Alex Hutchinson discussed this point recently on his blog (1). Part of it depends on how much fat you carry-- if you're already lean, the body is more likely to increase hunger because it very much dislikes going too low in body fat. Most overweight/obese people do not totally make up for the calories they burn through exercise by eating more, so they lose fat. There is a lot of individual variability here. The average obese person won't lose a substantial amount of fat through exercise alone. However, everyone knows someone who lost 50+ pounds through exercise alone, and the controlled trials support that it happens in a minority of people. On the other side of the spectrum, I have a friend who gained fat while training for a marathon, and lost it afterward.
Read more »
Basically, burning calories through exercise causes some people to eat more, but not everyone does, and a few people actually eat less. Alex Hutchinson discussed this point recently on his blog (1). Part of it depends on how much fat you carry-- if you're already lean, the body is more likely to increase hunger because it very much dislikes going too low in body fat. Most overweight/obese people do not totally make up for the calories they burn through exercise by eating more, so they lose fat. There is a lot of individual variability here. The average obese person won't lose a substantial amount of fat through exercise alone. However, everyone knows someone who lost 50+ pounds through exercise alone, and the controlled trials support that it happens in a minority of people. On the other side of the spectrum, I have a friend who gained fat while training for a marathon, and lost it afterward.
Read more »
Sunday, April 15, 2012
Next Primal Chef Event Sunday 5/20
Gil Butler has been working on a television show called Primal Chef, where he invites local chefs to make creative dishes from a list of Paleo ingredients, in a designated amount of time. The format is reminiscent of Iron Chef. The food is judged afterward by figures in the Paleo community. Robb Wolf was a judge on the first episode.
Gil has invited me to be a judge on the next show, along with Sara Fragoso and Dr. Tim Gerstmar. The next day, Sunday April 20th, Gil is organizing a catered Primal Chef event in Seattle, with Paleo dinner, speakers, entertainment, prizes, and a screening of part of Paleo Chef episode 1. You can read the details and sign up here. I won't be speaking because I don't have time to put together another talk right now, but I will be attending the event.
Gil has invited me to be a judge on the next show, along with Sara Fragoso and Dr. Tim Gerstmar. The next day, Sunday April 20th, Gil is organizing a catered Primal Chef event in Seattle, with Paleo dinner, speakers, entertainment, prizes, and a screening of part of Paleo Chef episode 1. You can read the details and sign up here. I won't be speaking because I don't have time to put together another talk right now, but I will be attending the event.
Saturday, April 14, 2012
Lepromatous leprosy
The answer to yesterday's diagnostic challenge is #2. Leprosy.
Most of you were correct. The patient's face had multiple nodular lesions that coalesced into plaques. After 9 months of multidrug treatment the skin infiltration and weakness in the left eyelid had diminished.
Leprosy is caused by the bacterium, Mycobacterium leprae. It is not very contagious and has a long incubation
Thursday, April 12, 2012
What is the Diagnosis?
Today's diagnostic challenge is from The New England Journal of Medicine and it is pretty straight forward. Click on the image for a better view and make your diagnosis. Check back tomorrow for the answer.
1. Granulomatosis with polyangitis
2. Lepromatous leprosy
3. Neurofibromatosis type 1
4. Sarcoidosis
5. Tertiary syphilis
Don't be shy. Post your guess in the comments section.
Tuesday, April 10, 2012
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
Read more »
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
Read more »
Friday, April 6, 2012
Doc Groups Identify Unnecessary Tests
When nine prestigious Medical Specialty Groups get together and identify tests that are unnecessary and wasteful, it is time to take notice. In a rare effort, each specialty identified 5 tests and procedures that do not add value and that may be unnecessary or overused. In all, 45 tests and procedures were listed as part of the ABIM "Choosing Wisely" campaign, a multiyear initiative that
Global Meat Production, 1961-2009
Total global meat production per person has steadily increased from 0.13 lbs per day in 1961 to 0.29 lbs per day in 2009*, a 120 percent increase over the last half century (currently in the US, average meat consumption is about half a pound per day). Since meat consumption in the US and Europe has only increased modestly over time, this change mostly reflects greatly increased meat consumption over the last half century in developing countries** in Asia, Africa and South America. In 1961, it's likely that most of the 0.13 pounds per day of meat was consumed in affluent countries such as the US, with not much consumed elsewhere (with some exceptions). Historically, meat has always been expensive relative to other food sources in agricultural societies, so it's eaten by those who can afford it.
Read more »
Wednesday, April 4, 2012
Doctors Coat Helps Focused Attention
A recent study in the Journal of Experimental Social Psychology found that wearing the white coat of a doctor caused the person to focus and pay more attention. Wearing the white coat of a painter or other occupation didn't have the same effect. The scientists call this enclothed cognition: the effects of clothing on cognitive processes.
The experiment was done with 58 undergraduates who
Tuesday, April 3, 2012
The Supreme Court and Health Care Act
The Nation is anxiously awaiting the ruling of the Supreme Court on the Health Reform Act (Accountable Care Act..aka: Obamacare) which will be announced in June. The 6 days of hearings were unprecedented in their partisan tone and we got a good idea of how the justices will vote. But no-one can truly predict how it will turn out until the last minute. Each one has already rendered a private
Sunday, April 1, 2012
Toxic Sugar
I watched "60 Minutes" tonight and it reinforced my evolving understanding that refined sugar is toxic for the human body. Dr Lustig, a pediatric endocrinologist at UCSF, was interviewed along with other researchers and the evidence strongly confirms just how bad sugar is for us. We know about its contribution to obesity and diabetes, but now research shows sugar raises LDL cholesterol, the
The Eocene Diet
65 million years ago, a massive asteroid slammed into the Yucatan peninsula, creating a giant dust cloud that contributed to the extinction of terrestrial dinosaurs. In the resulting re-adjustment of global ecosystems, a new plant tissue evolved, which paved the way for the eventual appearance of humans: fruit. Fruit represents a finely crafted symbiosis between plants and animals, in which the plant provides a nourishing morsel, and the animal disperses the plant's seeds inside a packet of rich fertilizer.
Fruit was such a powerful selective pressure that mammals quickly evolved to exploit it more effectively, developing adaptations for life in the forest canopy. One result of this was the rapid emergence of primates, carrying physical, digestive and metabolic adaptations for the acquisition and consumption of fruit and leaves. Primates also continued eating insects, a vestige of our early mammalian heritage.
Read more »
Fruit was such a powerful selective pressure that mammals quickly evolved to exploit it more effectively, developing adaptations for life in the forest canopy. One result of this was the rapid emergence of primates, carrying physical, digestive and metabolic adaptations for the acquisition and consumption of fruit and leaves. Primates also continued eating insects, a vestige of our early mammalian heritage.
Read more »
Subscribe to:
Posts (Atom)