This will be a departure from my usual posts. Several announcements in the news and medical journals have caught my attention recently, and as I delved into the details, I thought I would share them with our SBM readers. Topics include AIDS cures, the continuing danger of polio, eating nuts for longevity, racial differences in vitamin D, and the use of pharmacogenetic testing to guide the dosage of anticoagulant drugs. They are all examples of science-based medicine in action.
Have patients been cured of AIDS?
I read that the HIV virus had returned in patients thought to have been cured by bone marrow transplants, and I mistakenly thought they were referring to the original claim of cure I had read about. Nope, that one still stands. (more…)
Suffer the lab rats
Elsevier has announced that they are retracting the infamous Seralini study which claimed to show that GMO corn causes cancer in laboratory rats. The retraction comes one year after the paper was published, and seems to be a response to the avalanche of criticism the study has faced. This retraction is to the anti-GMO world what the retraction of the infamous Wakefield Lancet paper was to the anti-vaccine world.
The Seralini paper was published in November 2012 in Food and Chemical Toxicology. It was immediately embraced by anti-GMO activists, and continues to be often cited as evidence that GMO foods are unhealthy. It was also immediately skewered by skeptics and more objective scientists as a fatally flawed study.
The study looked at male and female rats of the Sprague-Dawley strain of rat – a strain with a known high baseline incidence of tumors. These rats were fed regular corn mixed with various percentages of GMO corn: zero (the control groups), 11, 22, and 33%. Another group was fed GMO corn plus glyphosate (Round-Up) in their water, and a third was given just glyphosate. The authors concluded: (more…)
It is a triumph of marketing over evidence that millions take supplements every day. There is no question we need vitamins in our diet to live. But do we need vitamin supplements? It’s not so clear. There is evidence that our diets, even in developed countries, can be deficient in some micronutrients. But there’s also a lack of evidence to demonstrate that routine supplementation is beneficial. And there’s no convincing evidence that supplementing vitamins in the absence of deficiency is beneficial. Studies of supplements suggest that most vitamins are useless at best and harmful at worst. Yet the sales of vitamins seem completely immune to negative publicity. One negative clinical trial can kill a drug, but vitamins retain an aura of wellness, even as the evidence accumulates that they may not offer any meaningful health benefits. So why do so many buy supplements? As I’ve said before, vitamins are magic. Or more accurately, we believe this to be the case.
There can be many reasons for taking vitamins but one of the most popular I hear is “insurance” which is effectively primary prevention – taking a supplement in the absence of a confirmed deficiency or medical need with the belief we’re better off for taking it. A survey backs this up – 48% reported “to improve overall health” as the primary reason for taking vitamins. Yes, there is some vitamin and supplement use that is appropriate and science-based: Vitamin D deficiencies can occur, particularly in northern climates. Folic acid supplements during pregnancy can reduce the risk of neural tube defects. Vitamin B12 supplementation is often justified in the elderly. But what about in the absence of any clear medical need? (more…)
I’m sure I’m not the only health professional that bites their tongue whenever a patient starts a question with “I heard on Dr. Oz that…” More often than not, I have expectations to realign, and some assumptions to correct. I could easily devote all my posts to simply correcting information presented on the Dr. Oz show. But given I’m blogging here biweekly, and Dr. Oz has a daily television show, I’ll never be able to catch up. So while my first choice in topics isn’t to add a post to our extensive Dr. Oz archives, I often end up, like many other health professionals, needing to respond to his shows shortly after they air.
Should you happen to be someone that has never seen the Dr. Oz show, Dr. Mehmet Oz is an Oprah protégé who has gone on to build a health media empire that is possibly the biggest vehicle for health pseudoscience and medical quackery on television. Whether it’s promoting homeopathy, recommending unproven supplements, or advocating ridiculous diet plans, there seems to be no health subject too dubious to endorse. Oz has established an impressive track record of providing highly questionable health advice. A few months ago I examined his absurd endorsement of green coffee beans, followed by his dubious “clinical trial” of green coffee beans that likely didn’t meet minimal research ethics standards. Then there was the weight loss “miracle” (his words), red palm oil, which followed the same episodic formula of breathless hyperbole backed by questionable evidence. One of the meta-trends of the Dr. Oz show are weight loss secrets – typically gimmicky interventions, supplements and therapies that he promotes as panaceas for obesity. (more…)
It’s likely you know someone who has bought into the notion that nutrition is everything, the source of all health and the cause of all illness. Nutrition is very important, to be sure, but it is only one of many possible causes of disease, and if you live in a Western industrialized nation you probably have adequate nutrition. The notion, however, that food can heal is powerfully alluring, and it makes great headlines. The result is that people who read the headlines for the latest food to avoid, or the latest ingredient that will make them live longer or stave off disease, seem to have an association for everything. Eating around them is to be constantly told that food X is good for you and will prevent Y, or that some other food should be avoided because it causes Z.
Red peppers will help prevent cancer and help you lose weight. Garlic will help prevent heart disease and aids in iron metabolism. Cayenne pepper prevents strokes. Peaches prevent heart disease and cancer. In fact- think of any food at random and type “random food health benefits” into Google and chances are you will be rewarded with a list of the amazing health benefits of whatever food you wish.
My usual response when offered such advice is – you know, food is healthy for you. I recommend you eat food every day. Food is full of nutrition, essential vitamins and minerals, and will give you energy. If you don’t eat food, your health with dramatically suffer. But don’t eat too much food – that’s not healthful.
A Swedish researcher, Staffan Lindeberg, has been studying the inhabitants of Kitava, one of the Trobriand Islands of Papua New Guinea. He claims that sudden cardiac death, stroke, and exertion-related chest pain never occur in Kitava; and he attributes this to their eating a Paleolithic diet.
2,250 people live on Kitava. They are traditional farmers. Their dietary staples are tubers (yam, sweet potato and taro), fruit, fish, and coconut. They don’t use dairy products, alcohol, coffee, or tea. Their intake of oils, margarine, cereals, and sugar is negligible. Western foods constitute less than 1% of their diet. Their activity level is only slightly higher than in Western populations. 80% of them smoke daily and an unspecified number of them chew betel. The macronutrient composition of the Kitavan diet was estimated as 21% of total calories from fat, 17% from saturated fat, 10% from protein, and 69% from carbohydrates.
Lindeberg’s Kitava study examined a sample of 220 Kitavans aged 14-87 and compared them to healthy Swedish populations. They found substantially lower diastolic blood pressure, body mass index, and triceps skinfold thickness in the Kitavans. Systolic blood pressure was lower in Kitava than in Sweden for men over 20 and women over 60. Total cholesterol, LDL cholesterol, and apolipoprotein B were lower in men over 40 and in women over 60. Triglycerides were higher in Kitavans aged 20-39 than in Swedes of the same age. HDL was not significantly different. (more…)
I never used to write much about genetically modified organisms (GMOs) before. I still don’t do it that often. For whatever reason, it just hasn’t been on my radar very much. That seems to be changing, however. It’s not because I went seeking this issue out (although I must admit that I first became interested in genetic engineering when I was in junior high and read a TIME Magazine cover article about it back in the 1970s), but rather because in my reading I keep seeing it more and more in the context of anti-GMO activists using bad science and bad reasoning to justify a campaign to demonize GMOs. Now, I don’t have a dog in this hunt, (Forgive me, I have no idea why I like that expression, given that I don’t hunt.) I really don’t. I was, not too long ago, fairly agnostic on the issue of GMOs and their safety, although, truth be told, because I have PhD in a biomedical science and because my lab work has involved molecular biology and genetics since I was a graduate student in the early 1990s, I found the claims of horrific harm attributable to GMOs not particularly convincing, but hadn’t bothered to take that deep a look into them. It was not unlike my attitude towards the the claims that cell phones cause cancer a few years ago, before I looked into them and noted the utter lack of a remotely-plausible mechanism and uniformly negative studies except for a group in Sweden with a definite ax to grind on the issue. Back then, I realized that there wasn’t really a plausible mechanism by which radio waves from cell phones could cause cancer in that the classic mechanisms by which ionizing radiation can break DNA molecular bonds and cause mutations don’t apply, but I didn’t rule out a tiny possibility that there might be an as-yet unappreciated mechanism by which long term exposure to radio waves might contribute to cancer. I still don’t, by the way, which has gotten me into the odd kerfuffle with some skeptics and one physicist, but I still view the likelihood that cell phone radiation can cause cancer as being just a bit more plausible than homeopathy.
As was the case for the nonexistent cell phone-cancer link, there has now been a steady drip-drip-drip of bad studies touted by anti-GMO activists as “evidence” that GMOs are the work of Satan that will corrupt or kill us all (and make us fat, to boot). Not too long ago, I came across one such study, a truly execrable excuse for science by Gilles-Eric Séralini at the University of Caen purporting to demonstrate that Roundup-resistant genetically modified maize can cause horrific tumors in rats. I looked at the methods and conclusions and what I found was some of the worst science I had ever seen, every bit as bad as the quack “science” used by the antivaccine movement. It wasn’t for nothing that I made the comparison, because the anti-GMO movement is very much like the antivaccine movement and the cranks who claim that cell phone radiation causes cancer. As if to demonstrate that very point, last week I came across an article by the all-purpose crank to rule all cranks, Mike Adams, at NaturalNews.com entitled GMO feed turns pig stomachs to mush! Shocking photos reveal severe damage caused by GM soy and corn:
Kim, Khloe and Kourtney Kardashian permit the use of their names and images of their curvaceous bodies to promote “QuickTrim” diet products, a line of dietary supplements making overblown claims typical of the weight loss supplement industry. Their personal testimonies and formidable publicity machine (Kim alone has over 13 million followers on Twitter), “has reportedly generated $45 million in revenue since they struck the deal with New Jersey-based Windmill Health Products in 2009,” according to the N.Y. Post. Naturally, the sisters are paid for their efforts, although how that amount is calculated or how much they receive apparently is not a matter of public record.
If you grew up in the seventies, you may remember the same food fads as I do. There was the oat bran buzz that was replaced by the wheat germ movement, the family fondue set and the homemade yogurt maker. And for a while I remember my father making what I called “aquarium water” – a foul-looking jug sitting on the kitchen counter with a gelatinous white mass floating on top. Despite the assurances it was good for me, I declined the taste tests. They didn’t push it and I never volunteered to drink this “cure all”. I thought kombucha had gone the way of gelatin-based salads and entrees, until a friend told me she was drinking it. Not only is it still a home-brew darling, kombucha isn’t just for hippies: There’s probably some for sale at your local organic grocery. Yet after a bit of digging, kombucha culture still seems mired in the 1970s. It’s still touted as a panacea, and it’s still one of the more questionable folk remedies out there. (more…)
In a former life, when I was an Air Force doctor, one of my duties was to give “Healthy Heart” briefings with a script furnished by Air Force experts. It covered the scientific consensus of the time (the early 80s) about diet. It recommended a low fat diet, restricted cholesterol and saturated fat, and demonized tropical oils like palm oil and coconut oil. (Trans fats weren’t yet on the agenda.)
Times have changed. Today we are more lenient about cholesterol in the diet, less concerned about total fat and saturated fat, and more concerned about trans fats. While many major health organizations still discourage its use, coconut oil has not only been rehabilitated in the public mind, but all kinds of health benefits are being claimed for it.
The fats in coconut oil
Coconut oil is high in saturated fats; it contains more saturated fatty acids than any other non-hydrogenated oil. It is stable and has a long shelf life. It is used in movie theaters to pop popcorn and in South Asian cuisine for dishes like curries. A hydrogenated version of coconut oil is an ingredient in non-dairy creamers. Much of the research done on coconut oil studied hydrogenated or partially hydrogenated forms. According to an article in the New York Times:
Partial hydrogenation creates dreaded trans fats. It also destroys many of the good essential fatty acids, antioxidants and other positive components present in virgin coconut oil. And while it’s true that most of the fats in virgin coconut oil are saturated, opinions are changing on whether saturated fats are the arterial villains they were made out to be. “I think we in the nutrition field are beginning to say that saturated fats are not so bad, and the evidence that said they were is not so strong,” Dr. Brenna said.
Coconut oil contains lauric acid, which raises both HDL and LDL cholesterol levels. This may improve the cholesterol profile, although there are concerns that it may promote atherosclerosis by other means. Virgin coconut oil contains medium-chain triglycerides, which are not as risky as some other saturated fats.