Month: November 2007

Who Reads Blogs?

Seth RobertsLeave a comment

An article in the current issue of the American Journal of Epidemiology is about participants in a large health survey. It compares people who turned in the questionnaire via the Web with those who answered via mail.

Over 50% of 77,047 participants chose to enroll in the study via the Web . . . The authors compared the demographic and health characteristics of Web responders with those of paper responders. Web responders were slightly more likely to be male, to be younger, to have a high school diploma or college degree, and to work in information technology or another technical occupation. Web responders were more likely to be obese and to smoke more cigarettes and were less likely to be problem alcohol drinkers and to report occupational exposures.

The study began in 2001.

In Japanese

Seth RobertsLeave a comment

If you read Japanese you can read about the Shangri-La Diet here:

https://www.suda.tv/archives/2007/03/post_580.php
https://ameblo.jp/pb-038434/entry-10044923240.html
https://groundhogday.seesaa.net/article/7497773.html

And even if you don’t read Japanese you can appreciate the excellent illustration here:

https://dietxdiet.ojaru.jp/Shangri-la/

and the great blog name (my nonsequitur) and banner here:

https://www.owl-tottori.jp/diet/jijou-bn/shangriradiet.html

Thanks to Pearl Alexander.

Omega-3 and Cognitive Function in the Elderly: The Opposite Result

Seth RobertsLeave a comment

Peter Spero has sent me the following abstract from a paper published in 2003 in the Journal of Alzheimer’s Disease:

It has been suggested that the dietary intake of omega-3 polyunsaturated fatty acids could be inversely related to the risk of dementia and cognitive decline. This analysis examined the association between plasma concentration of omega-3 polyunsaturated fatty acids and prevalence and incidence of cognitive impairment and dementia. Data are reported on subjects 65 years or older who had a complete clinical evaluation at the first two waves (1991-1992 and 1996-1997) of the Canadian Study of Health and Aging. Main outcome measures were cognitive impairment and dementia by mean relative plasma concentrations of fatty acids in the phospholipid fraction at baseline. Results were adjusted for age, sex, education, smoking, alcohol intake, body mass index, history of cardiovascular disease, and apolipoprotein E e4 genotype. In the cross-sectional analysis, no significant difference in omega-3
polyunsaturated fatty acid concentrations was observed between controls and both prevalent cases of cognitive impairment and dementia. In the prospective analysis, a higher eicosapentaenoic acid (p < 0.01) concentration was found in cognitively impaired cases compared to controls while higher docosahexaenoic acid (p < 0.07), omega-3 (p < 0.04) and total polyunsaturated fatty acid (p < 0.03) concentrations were found in dementia cases. These findings do not support the hypothesis that omega-3 polyunsaturated fatty acids play a protective role in cognitive function and dementia.

The people with worse-functioning brains had more omega-3 in their blood than everyone else. Which is opposite to one of the two studies I described yesterday.

I’d love to have seen what reviewers made of this.

The Resource Curse

Seth RobertsLeave a comment

In an excellent Authors@Google talk based on his book The Birth of Plenty — about the increase in GDP growth that started around the Industrial Revolution — William Bernstein mentions what he calls “The Resource Curse”:

If all your wealth comes out of a couple of holes in the ground, the quickest way to become wealthy . . . is control of those holes and access to those holes. It breeds corruption, and it breeds poor government, and it drains the entrepreneurial spirit. The best way to get rich is to have no natural resources at all. Think Singapore, think Japan.

Could the same be true of science? Could access to resources — say, a lot of grant money or expensive equipment — breed corruption and poor government, and drain the entrepreneurial spirit? It isn’t obvious why not. Surely human nature is essentially the same in both places. This may have something to do with Gary Taubes’ complaints about poor nutritional science in Good Calories, Bad Calories.

I rarely mention in this blog my animal learning research, which in recent years has been about exactly this — with animals (rats and pigeons). The results of our experiments are easy to sum up: When animals have access to rich sources of food, it drains the entrepreneurial spirit. In psychology-speak, when the probability of reward for actions is high, there is less variation in what animals do than when the probability of reward is low. I got into this line of research by accident.

Omega-3 and Cognitive Function in the Elderly

Seth Roberts3 Comments

Two papers in the latest issue of the American Journal of Clinical Nutrition provide more support for the idea that omega-3s improve brain function.

The first was a cross-sectional study involving about 2000 persons 70-74 years old in Norway. Their fish consumption was measured and they took a battery of cognitive tests. The more fish you ate, the better your score on every test, even after adjustment for several things.

The second used data collected as part of a 3-year experiment about something else (the effect of folic acid) with 800 persons aged 50-70. They measured the omega-3 concentrations in the blood of their subjects. Would these predict anything? Their results were more ambiguous:

Higher plasma n–3 PUFA proportions predicted less decline in sensorimotor speed . . . and complex speed . . . over 3 y. Plasma n–3 PUFA proportions did not predict 3-y changes in memory, information-processing speed, or word fluency. The cross-sectional analyses showed no association between plasma n–3 PUFA proportions and performance in any of the 5 cognitive domains.

Cross-sectional correlations between a measure of omega-3 (fish consumption) and cognitive performance are exactly what the first study did find.

How Bad is Saturated Fat?

Seth RobertsLeave a comment

This Men’s Health article is a nice summing-up of the lack of evidence that saturated fat is bad.

In 2000, a respected international group of scientists called the Cochrane Collaboration conducted a “meta-analysis” of the scientific literature on cholesterol-lowering diets. After applying rigorous selection criteria (219 trials were excluded), the group examined 27 studies involving more than 18,000 participants. Although the authors concluded that cutting back on dietary fat may help reduce heart disease, their published data actually shows that diets low in saturated fats have no significant effect on mortality, or even on deaths due to heart attacks. “I was disappointed that we didn’t find something more definitive,” says Lee Hooper, Ph.D., who led the Cochrane review. If this exhaustive analysis didn’t provide evidence of the dangers of saturated fat, says Hooper, it was probably because the studies reviewed didn’t last long enough, or perhaps because the participants didn’t lower their saturated-fat intake enough. Of course, there is a third possibility, which Hooper doesn’t mention: The diet-heart hypothesis is incorrect.

Thanks to Dave Lull.

Omega-3 and Veterinary Medicine

Seth RobertsLeave a comment

The November 2007 issue of Acres USA, a magazine about organic/sustainable farming, has an article (not online) about using omega-3s to cure farm-animal problems. Here are the best parts:

One family reported that their dog had failed obedience training three times. Our therapy of cod liver oil (Nordic Naturals), Fasttrack probiotic, and a homeopathic prescription enabled him to pass on the next attempt. . . . Dogs experience panic attacks for a variety of reasons. One frantic German shepard dog jumped through a plate glass window to escape the house and get near his owner. The solution to his panic and anxiety attacks proved to be cod liver oil, the correct homeopathic medicine, and a whole-food diet rich in omega-3 oils and quality live probiotics.

The obedience-training story resembles my story of taking flaxseed oil capsules and the next morning being able to easily put on my shoes standing up. With the difference that I’d had trouble several hundred times in a row, not just three.

Thanks to Joshua Schrier.

How to Start a Food Demo Company

Seth RobertsLeave a comment

At the Berkeley Whole Foods a few days ago, a friendly man named Hunter Austin was demoing Alvarado Street Bakery Sprouted Wheat bread. “Baked locally, sold [frozen] nationally,” he said. He was giving out little grilled cheese sandwiches. It turned out he had his own demo company — food companies hire him to demo their products. He had started the company four years ago. Before that he had owned and run a restaurant. He made lots of money but he was working seven days a week. The pay worked out to $15/hour.

Why did you choose this as your escape route? I asked. “You want to know the truth?” he said. “Because it looked really easy.” He did demos for someone else for a few months then decided to strike out on his own. He made a brochure advertising his services. Then he went up and down the aisles at a supermarket writing down the names and addresses of companies whose products he liked. He sent them his brochure. What happened? I asked. “I got business,” he said.

That’s how his business began. It turned out to be harder than it looked. “The first ten demos are fun,” he said, “the next twenty are sobering, and after that it’s a job.” Now he mostly hires people to do the actual work. This was the rare demo he did himself. His company is called Demo Demon.

My Theory of Human Evolution (Hallelujah edition)

Seth Roberts6 Comments

The latest episode of Ugly Betty ended with Jeff Buckley’s version of Leonard Cohen’s Hallelujah. I was entranced. I ran to YouTube to hear the whole thing:

What a great performance! Could anyone else come close? I usually like Rufus Wainwright:

Not close.

K. D. Lang?

No.

Leonard Cohen himself?

Well, the best of the rest.

I am a lot more interested in Jeff Buckley than I was an hour ago. From Wikipedia: “The night before his death [by drowning], Buckley excitedly told his girlfriend Joan Wasser that he believed he had found the cause of his dramatic moods, namely bipolar disorder.”