The health conscious and trendy public are a bit obsessed with the food they consume. This can be a good thing, to the extent that it results in a more healthful diet, but unfortunately those interested in improving their diet must wade through a great deal of misinformation before getting to accurate and helpful information.
For example, I recently gave a lecture (ironically on health information) at Google (you can view the entire talk here). Google is a progressive company that tries to help their employees stay healthy. They provide many snack stations and helpfully divide snacks into red, yellow, and green shelves. Employees can freely choose whatever snacks they want, but they are gently encouraged to choose from the more healthful green shelf and avoid the unhealthy red shelf. I noticed that beverages sweetened with sugar cane were placed on the green shelf, while those sweetened with artificial sweeteners like aspartame or Splenda were slumming on the red shelf. It was ironic to see such a high-tech company falling for the naturalistic fallacy.
Sugar cane sweetened sodas are becoming fashionable, mainly to avoid high fructose corn syrup (HFCS), which many claim is associated with obesity and increased cardiovascular risk. Jim Laidler did an excellent job reviewing this controversy two years ago on SBM. To me this represents a general tendency to try to understand a complex question by oversimplifying, specifically by avoiding perceived “villains.” It may seem overwhelming to grapple with all the complex information involved in basic dietary health choices, like which beverages are best. Following simple rules, such as avoiding single ingredients that are perceived to be “bad,” therefore has an appeal. I also think this is part of the appeal of the naturalistic fallacy, a simple litmus test to what is good vs bad.
A recent meta-analysis of acupuncture studies for chronic pain by Vickers et al is getting a great deal of press. The authors’ conclusions are:
Acupuncture is effective for the treatment of chronic pain and is therefore a reasonable referral option. Significant differences between true and sham acupuncture indicate that acupuncture is more than a placebo. However, these differences are relatively modest, suggesting that factors in addition to the specific effects of needling are important contributors to the therapeutic effects of acupuncture.
News reports generally reflect this conclusion – acupuncture works, but mostly (although not entirely) through placebo effect, but that’s OK.
I took a close look at the study and find that the authors display considerable pro-acupuncture bias in their analysis and discussion. They clearly want acupuncture to work. That aside, the data are simply not compelling, and the authors, in my opinion, grossly overcall the results, which are compatible with the conclusion that there are no specific effects to acupuncture beyond placebo.
A recent review of 240 studies has concluded that:
The published literature lacks strong evidence that organic foods are significantly more nutritious than conventional foods. Consumption of organic foods may reduce exposure to pesticide residues and antibiotic-resistant bacteria.
Organic produce has become increasingly popular in recent years. There are several reasons that consumers might prefer organic produce, including the belief that organic farming is better for the environment and more sustainable. I am going to focus in this article about the health effects of organic produce. Environmental claims for organic farming are complex and controversial – I will just say that such claims largely fall prey to the naturalistic and false dichotomy fallacies. In my opinion, farming practices should be evaluated on their own merits individually, based on evidence rather than philosophy. Sustainable and environmentally friendly farming are certainly laudable goals and I support farming practices promote them, however they are labeled.
The alleged superiority of organically grown produce is a separate question. In a 2003 survey 68.9% of people who purchase organic food said they did so because they believed it to be healthier (more than any other reason given). However, fifty years of research has so far not produced convincing evidence that there is any health benefit to consuming organic food. Likewise, systematic reviews of nutritional quality of organic produce also reveals no difference from conventional produce.
I love reading quotes by the likes of Karl Popper in the scientific literature. A recent replication of Bem’s infamous psi research, Feeling the Future, gives us this quote:
Popper (1959/2002) defined a scientifically true effect as that “which can be regularly reproduced by anyone who carries out the appropriate experiment in the way prescribed.”
The paper is the latest replication of Daryl Bem’s 2011 series of 9 experiments in which he claimed consistent evidence for a precognitive effect, or the ability of future events to influence the present. The studies were published in The Journal of Personality and Social Psychology, a prestigious psychology journal. All of the studies followed a similar format, reversing the usually direction of standard psychology experiments to determine if future events can affect past performance.
In the 9th study, for example, subjects were given a list of words in sequence on a computer screen. They were then asked to recall as many of the words as possible. Following that they were given two practice sessions with half of the word chosen by the computer at random. The results were then analyzed to see if practicing the words improved the subject’s recall for those words in the past. Bem found that they did, with the largest effect size of any of the 9 studies.
Be careful what you wish for. In the last few decades purveyors of dubious medical treatments and products have been trying to go mainstream, and they have had some unfortunate success. They asked for serious scientific investigation into their claims – and they got it. They asked to be treated like real medicine (but not really, they only want the trappings of legitimacy, not the substance), and when they actually are treated with the standards similar to science-based medicine, they cry foul.
The response of the fake-medicine lobby is not to alter their claims to fit the evidence, or to carry out better studies, or to clean up their act when problems are brought to their attention – but to attack their critics.
Homeopathy is perhaps the best example of this behavior. Homeopathy’s biggest marketing advantage is that most people don’t know what it really is. They think it’s “natural” medicine or herbs. That is why, during homeopathy awareness week, I was happy enough to oblige. I want people to know exactly what homeopathy is – sugar pills. They are placebos on which the equivalent of a magical ritual has been cast. Active ingredients, which themselves are as fanciful as fairy dust, are diluted into non-existence.
The headline of a recent Los Angeles Times article is, “No yolk: eating the whole egg as dangerous as smoking?” The question mark is meant to convey uncertainty or surprise, or perhaps both. The article represents much of what is wrong with science and health reporting by mainstream media.
The news report is based upon an article published in Atherosclerosis – Egg yolk consumption and carotid plaque. The study is highly problematic in ways not explored at all in the LA Times article. The researchers surveyed 1,262 patients seen in a vascular prevention clinic, asking them about their egg consumption, smoking history, and other lifestyle factors. They created a measure known as “egg yolk years” – the number of egg yolks consumed on average per week times the number of years of consumption. They compared this to pack years of smoking – packs per day times number of years, a routine method of reporting smoking history.
“Our findings suggest that regular consumption of egg yolk should be avoided by persons at risk of cardiovascular disease. This hypothesis should be tested in a prospective study with more detailed information about diet, and other possible confounders such as exercise and waist circumference.”
I have nothing against berries. I, in fact, enjoy many kinds of berries in my diet. My favorite fruit, the banana, is actually a berry (botanically speaking). I am disturbed, however, at the extent to which various kinds of berries are being sold as the latest superfood cure-all.
Dr. Oz, for example, has been pushing the lingonberry (a relative of the cranberry and blueberry) as “a new superfruit for longevity.” An attached article on his site states:
“Today, scientists are showing its value in both human and animal studies that are proving to have positive results.”
Curiously, there are no links or references to these studies.
Polyphenols and Antioxidants
We are still in the midst of the “antioxidant craze” – if you read the justification for just about any so-called “superfood” or longevity supplement you are sure to read about antioxidants. I have already covered antioxidants, but briefly: Cell metabolism in part creates oxygen free radicals which are molecules that steal electrons from other molecules, causing a cascade of reactions that can damage proteins and other chemicals in the body. Anti-oxidants are chemicals that can stop free radicals and limit the damage. They therefore decrease “oxidative stress” on cells. So far it sounds like anti-oxidants are therefore a good thing and we should be gobbling up as much as we can. However – free radicals and anti-oxidants exist in cells in a homeostasis. Free radicals are used by the immune system, for example, to fight invading organisms. They are also important signaling molecules, triggering other cell-protective mechanisms.
There is a movement in the US to oppose a public health measure that is backed by impressive evidence showing it is safe and effective, as well as highly cost effective. For as long as the government has supported this health measure, there have been those opposed to it, claiming (against the evidence) that it is unsafe, ineffective, and represents a violation of personal freedom and the right to refuse an unwanted medical intervention. I could be talking about vaccines and the anti-vaccine movement, but in this case I am talking about the fluoridation of public water supplies and the antifluoridation movement.
This social debate (there isn’t much of a scientific debate) crops up in the news every now and then – mostly prompted by an antifluoridation activist or group making noise, or by a local referendum to block fluoridation in a community. Recently there has been a Harvard study making the rounds of social media, Developmental Fluoride Neurotoxicity: A Systematic Review and Meta-Analysis. The actual findings of the study do not show that there is any risk to public water fluoridation (if anything, they show that it is safe), but the study was seized upon by antifluoridation activists and distorted for their propaganda purposes. Unfortunately, the internet is now fertile ground for the spreading of propaganda.
The NYS Coalition Opposed to Fluoridation put out a press release distorting the findings of the study. Their press release (“Harvard Study Finds Fluoride Lowers IQ – Published in Federal Gov’t Journal”) was then printed as a science news item by many online news outlets. Reprinting press releases, without any editorial filter, is a cheap and easy way to add news-like content to your website. The Sacramento Bee, for example, published the press release under their “News” tab. Near the top of the page, in small print, they did put a disclaimer (which is better than most sites):
This section contains unedited press releases distributed by PR Newswire. These releases reflect the views of the issuing entity and are not reviewed or edited by the Sacramento Bee staff. More information on PR Newswire can be found on their web site.
That’s better than nothing, but I wonder how many people reading the press release will notice and read the disclaimer. In my opinion, a news outlet should not reprint press releases sent out from advocacy organizations clearly intended to promote an agenda. They especially should not print them under the banner of “News.” The disclaimer is not adequate. The spreading of this “news item” around Facebook and other social media demonstrates this.
The Summer Olympics are coming up, which means that, in addition to world-class athletic performance, the public will be exposed to a variety of sports-related pseudoscience. This is not unique to the Olympics, of course. The world of sports competition is rife with pseudoscience, false claims, dubious products, superstitions, and magical charms. The most egregious example of this recently has been the energy bracelet scam — multiple companies have and are marketing little bits of rubber, plastic, or metal that you wear on your wrist and they claim (based on parlor tricks rather than evidence) will improve athletic performance. They give classically pseudoscientific explanations for the alleged effect, such as negative ions or energy frequencies. In fact the new icon of the entanglement of sports with pseudoscience is the Power Balance Stadium.
Occasionally the scientific community takes notice of such claims and bothers to review them. Also, in the internet age, the information is actually available to the public (rather than buried in an obscure journal). A recent joint investigation by BBC Panorama and the British Medical Journal (BMJ) recently found a shocking (to them) lack of evidence for many claims made to market performance-enhancing products. The BBC reports:
A team at Oxford University examined 431 claims in 104 sport product adverts and found a “worrying” lack of high-quality research, calling for better studies to help inform consumers.
High quality studies would be nice, but the article fails to ask the question — who is going to fund those studies? What incentive do manufacturers have in proving their products don’t work?
Since the development of the vaccine, perhaps the most effective public health measure we have yet devised, only one human disease has been completely eradicated from the world – smallpox. The last case was reported in Somalia in 1977. Eradication was the result of a deliberate and intense campaign, requiring almost complete vaccination of the population, especially in certain population dense areas. Countries such as India and Nigeria were among the last to achieve eradication. Some of the lessons learned were that very high compliance rates were needed and that even small communities could harbor the virus and prevent eradication.
Several decades later, at the beginning of the 21st century, we are on the verge of eradicating a second major human infectious disease, polio. Like smallpox, polio is a virus that has no major non-human host, so eradication is possible. The polio virus enters the anterior horn cells of the spinal cord, the lower motor neuron – cells that connect the brain to muscles. When those cells die muscles lose their connection causing weakness and atrophy. Vaccine campaigns have successfully eliminated polio from most countries, but the wild type of the virus remains endemic in Nigeria, India, Pakistan, and Afghanistan.
We have the potential, with one final push (which is being spearheaded by the World Health Organization – WHO) to eradicate wild type polio from the world, but these efforts are being hampered by politics and ideology.