We would all like to live longer. The most promising longevity research indicates that severe calorie restriction might extend life span, but such a diet is difficult to follow. Resveratrol, a phytochemical found in red wine, has been evaluated as a possible way out of the dilemma. When given to obese mice on a high calorie diet, it produced a number of changes associated with improved health, such as increased insulin sensitivity, and it increased survival. Perhaps by taking resveratrol you could eat as much as you want and get fat without suffering the usual consequences. Perhaps you could get the longevity benefits of severe calorie restriction without restricting calories.
In addition to fat mice, resveratrol also extends the life of Saccharomyces cerevisiae, Caenorhabditis elegans and Drosophila melanogaster (yeast, nematodes, and fruit flies). But a study in non-obese mice found no increase in survival (although it did find several signs of improved health). Besides the anti-aging claims, there is also some evidence from in vitro and animal studies that it might have cardiovascular effects and anti-cancer effects. (more…)
A news story on Science a Gogo reports that obesity is linked to stupidity, according to a new study based on brain scans. Apparently the reporter can’t read. That’s not at all what the study showed.
What the Study Really Said
The study was entitled “Brain structure and obesity.”It was published in Human Brain Mapping. There were 10 authors listed, with the two interviewed for the news report being the lead author (CA Raji) and the last listed author (PM Thompson). The study evaluated MRI scans of 94 elderly subjects who were cognitively normal and remained cognitively normal for at least 5 years after their scan. It found that obese people had 8 percent less brain tissue than people with normal weight, while overweight people had 4 percent less tissue. The deficits were in areas of the brain that have been associated with Alzheimer’s disease. The story reports that this put the subjects at high risk for Alzheimer’s disease. But the subjects remained cognitively normal for at least 5 years after the scan. They were not rendered stupid. They did not develop Alzheimer’s. They remained cognitively normal. You might also interpret the study as showing that obese patients with those findings on brain scan could be predicted not to develop Alzheimer’s or develop any other cognitive deficits for at least five years. (more…)
I recently chastised the American Family Physician (the journal of the American Academy of Family Physicians) for assigning a high SORT (strength of evidence) rating to acupuncture treatments that did not merit that rating. While the AAFP claims to strongly support evidence-based medicine, I have observed a gradual infiltration of CAM into their journal, their website, and their CME offerings. They seem to be more concerned with the popularity of CAM and with not offending its believers than with maintaining scientific rigor. The problem is only getting worse.
Recently a “News Now” article was published on the AAFP website: “New Report Details Billions Americans Spend on Complementary, Alternative Medicine: Physicians Can Benefit from Adding CAM to Their Practices, Says FP” It is very disturbing. (more…)
The Medical Letter, a highly respected source of reliable independent evaluations of drugs and therapeutics, has just published an evaluation of red yeast rice (Vol 51, Issue 1320, P 71-2, Sept 7, 2009). It has been widely promoted as a “natural” alternative to prescription medications for lowering blood LDL cholesterol levels. Studies have indeed shown that red yeast rice reduces LDL cholesterol levels and reduces the rate of major coronary events. The Medical Letter consultants concluded that it works, but they don’t recommend it. Why?
It’s Just Another Statin
When rice is fermented with the yeast Monascus purpureus, the resulting product contains numerous monacolins, which are naturally occurring HMG-CoA reductase inhibitors. One of these is identical to the prescription drug Mevacor (lovastatin). So it isn’t an alternative to prescription drugs, it’s just an alternative way of providing the same thing. (more…)
I subscribe to American Family Physician, the peer-reviewed journal of the American Academy of Family Physicians. It emphasizes evidence-based medicine and most articles include a table showing strength of evidence ratings for key recommendations for practice. Lately, its scientific rigor has been slipping. I have complained to the editor about several articles whose recommendations were not based on the best science, and I have been consistently ignored.
Acupuncture for Chronic Low Back Pain
A recent article on chronic low back pain recommended acupuncture and gave it an “A” rating corresponding to “consistent, good-quality patient-oriented evidence.” I wrote the following letter to the editor and to the author of the article: (more…)
The PowerPoint presentation that I gave at the Skeptic’s Toolbox workshop at the University of Oregon on August 7, 2009 is up on their website with the complete text of what I said. The theme of the workshop was scientific method. The title of my talk is “Tooth Fairy Science and Other Pitfalls: Applying Rigorous Science to Messy Medicine.” Click here for the link. It covers a lot of things that are pertinent to the subjects we discuss on this blog, and I thought some of our readers might enjoy it. I put in a lot of information and some good cartoons. Note: this was a talk to the general public, not an academic presentation, and it does not include citations or references.
Fear is a curious thing. It often bears no relation to the actual risk of what we fear. When swine flu first broke out in Mexico, people were understandably afraid. Travel was restricted, schools were closed, and so many people stayed home that the streets of Mexico City were empty. As the disease spread around the world, Egypt developed a paranoid fear of pigs and committed national pigicide. They ordered the slaughter of all 300,000 of their country’s innocent little porkers, ignoring the fact that the flu is spread person-to-person, not pig-to-person. Now that the disease has officially been labeled a pandemic, fears have switched from the real threat of the disease to an imagined danger from the vaccine.
Some people just plain hate the idea of vaccines – to the point that they are willing to spread old falsehoods, make up new lies, distort the results of studies, misrepresent statistics, and endanger our public health. There are websites like “Operation Fax to Stop the Vax” and even anti-swine-flu-vaccine rap videos. Press releases, e-mail campaigns, talk shows, and blogs are being used to stir up irrational fears. These people are irresponsible fearmongers. They are wrong, and they are dangerous.
A documentary film entitled “The Disappearing Male” was first shown on CBC in June, 2009. It can be viewed online here.
Some of its rhetoric is reminiscent of Chicken Little:
- “Where have all the boys gone?”
- “Millions of males are disappearing.”
- “We’re on the Titanic and we see the iceberg but we just can’t turn the ship.”
- “It may be a threat to the survival of the species.”
The claims behind the rhetoric are that male to female sex ratios at birth are decreasing, sperm quality and fertility are decreasing, and genitourinary birth defects like hypospadias are becoming more common. The film blames environmental chemicals, especially endocrine disruptors, and it claims they are causing “the most rapid period of evolution our species has ever seen” and that this may lead to our extinction. (more…)
Four years ago I received an e-mail inquiry about Protandim. I had never heard of it; but I looked it up and wrote a quick, informal, somewhat snarky answer that got posted on the Internet. It got a lot of attention. Googling for Protandim now brings up my critique right after the Protandim website itself: that can’t be good for sales. Over the years, several e-mails and blog comments have informed me that I was wrong (usually offering testimonials or calling me closed-minded), and recently I’ve been getting inquiries asking if I’ve changed my mind now that a clinical study has been published. I haven’t.
Instead of providing antioxidants directly, Protandim is supposed to stimulate the body to produce its own antioxidants. The website tells us it is “the only supplement clinically proven to reduce oxidative stress by 40%, slowing down the rate of cell aging to the level of a 20 year old.” It provides “thousands of times more antioxidant power than any food or conventional antioxidant supplement.” It signals the body’s genes to produce the enzymes SOD (superoxide dismutase) and CAT (catalase) that act as catalysts to neutralize free radicals and are not “used up” like ingested antioxidants are. It “creates a cascade of your body’s natural catalytic antioxidants that are able to destroy millions of free radicals per second.” It raises the level of glutathione by 300%. Glutathione is good, apparently.
What is Protandim? It’s a combination of Milk thistle, Bacopa extract, Ashwagandha, Green tea extract, and Turmeric extract. I looked these up in the Natural Medicines Comprehensive Database. None of them is known to have any significant clinical benefit from antioxidant effects. Some of them are listed as “not enough information” to know if they are safe. One has estrogenic properties and more than one has known side effects and potential interactions with other drugs. The only one that even sounds remotely like it might have some pertinent data behind it is green tea. Green tea contains antioxidant catechins that are “thought to possibly have a protective effect against atherosclerosis and heart disease” and contains flavonoids that “might reduce lipoprotein oxidation; however benefits have not yet been described in humans.”
A Pubmed search for “Protandim” yielded only 3 studies: One in mice, one in cell cultures and one in humans. (more…)
I recently wrote an article for a community newspaper attempting to explain to scientifically naive readers why testimonial “evidence” is unreliable; unfortunately, they decided not to print it. I considered using it here, but I thought it was too elementary for this audience. I have changed my mind and I am offering it below (with apologies to the majority of our readers), because it seems a few of our readers still don’t “get” why we have to use rigorous science to evaluate claims. People can be fooled, folks. All people. That includes me and it includes you. Richard Feynman said
The first principle is that you must not fool yourself–and you are the easiest person to fool.
Science is the only way to correct for our errors of perception and of attribution. It is the only way to make sure we are not fooling ourselves. Either Science-Based Medicine has not done a good job of explaining these vital facts, or some of our readers are unable or unwilling to understand our explanations.
Our commenters still frequently offer testimonials about how some CAM method “really worked for me.” They fail to understand that they have no basis for claiming that it “worked.” All they can really claim is that they observed an improvement following the treatment. That could indicate a real effect or it could indicate an inaccurate observation or it could indicate a post hoc ergo propter hoc error, a false assumption that temporal correlation meant causation. Such observations are only a starting point: we need to do science to find out what the observations mean. (more…)