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Energy Drinks

My stimulant of choice is coffee. I started drinking it in first-year university, and never looked back. A tiny four-cup coffee maker became my reliable companion right through graduate school. But since I stopped needing to drink a pot at a time, an entirely new category of products has appeared — the energy drink. Targeting students, athletes, and others seeking a mental or physical boost, energy drinks are now an enormous industry: from the first U.S. product sale in 1997, the market size was $4.8 billion by 2008, and continues to grow. (1)

My precious coffee effectively has a single therapeutic ingredient, caffeine. Its pharmacology is well documented, and the physiologic effects are understood. The safety data isn’t too shabby either: it’s probably not harmful and possibly is even beneficial. (I’m talking about oral consumption — no coffee enemas. Please.) In comparison, energy drinks are a bewildering category of products with an array of ingredients including caffeine, amino acids, vitamins, and other “natural” substances and assorted “nutraceuticals,” usually in a sugar-laden vehicle (though sugar-free versions exist). Given many products contain chemicals with pharmacologic effects, understanding the risks, signs of adverse events, and potential implications on drug therapy, are important.

So are energy drinks just candied caffeine delivery systems? Or are these syrupy supplements skirting drug regulations?

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Posted in: Herbs & Supplements, Nutrition, Politics and Regulation

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New Recommendations for Calcium and Vitamin D Intake

 A Walmart ad in my local newspaper trumpets “75% of all Americans don’t get enough Vitamin D” and offers to sell me Maximum Strength Vitamin D3, 5000 IU capsules to “promote bone, colon and breast health.” Meanwhile, the Institute of Medicine (IOM) tells me that “the majority of Americans and Canadians are receiving adequate amounts of … vitamin D” and that no one should take more than 4000 IU a day.  Apparently Walmart and the IOM aren’t talking to each other.

The media have been giving the impression that vitamin D is a new wonder drug. They have told us that we aren’t getting enough sunlight, that a large percentage of us suffer from vitamin D deficiency, and that low levels of vitamin D are associated with cancer, multiple sclerosis, peripheral vascular disease, diabetes, rheumatoid arthritis, Parkinson’s and Alzheimer’s disease, and other conditions. Low levels of vitamin D have been linked to higher overall mortality (but so have high levels of vitamin D!). The anti-vaccine folks have been telling us (without any controlled studies) that vitamin D supplements are better than vaccines for preventing influenza. There’s no good evidence that raising vitamin D levels with supplements actually prevents any of these conditions, but many people think it should, and doctors have increasingly been measuring blood levels and prescribing high dose supplements. Is this just another passing fad like the enthusiasm for vitamin C, or are we belatedly recognizing a serious deficiency problem?

I’ve had a lot of inquiries about “is this information trustworthy?” and “how much vitamin D should I be taking?” I’ve been telling people that I didn’t know, that recent findings will soon result in new recommendations, and I’ve been eagerly awaiting the new guidelines. Now we have them, thanks to the IOM. They are not what most of us anticipated. Since so many doctors had been advocating higher levels to prevent things like cancer, I thought official recommended intake levels would go up; instead, they went down.

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Posted in: Nutrition

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Cloned Beef

The controversy over the human consumption of meat and dairy products from cloned cows continues. The UK Advisory Committee on Novel Foods and Processes, after reviewing the evidence, concluded that there was no substantial difference between meat and dairy from cloned cows compared to conventional cows. However, food products from cloned animals and their offspring remain banned in Europe.

Use of offspring of cloned cows, sheep and pigs are legal in the US, South America, and Asia. Australia is likely to follow suit in a year or two. The European Union (EU) has an effective ban at the moment, but the policy is under review. The UK is also negotiating with the EU regarding the use of clones.

There is not much of a theoretical reason to suspect that cloned animals would present a health risk. The primary concern is that something unanticipated might have occurred during the cloning process, causing the animal to be genetically or developmentally abnormal. However, if the cloning process works properly this should not happen. Further, if mutations do occur, but the animal lives, it is likely that any changes do not represent a risk to humans who consume the meat or dairy from such clones.

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Posted in: Nutrition

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Bill Clinton’s Diet

Bill Clinton loved hamburgers from McDonald’s. He used to eat a typical American high calorie, high fat, meat-based diet. No more. He had a heart attack and a quadruple bypass in 2004. Recurrent blockages required placement of two stents in February 2010. This got his attention and he went on a strict new diet, losing 24 pounds to get back down to what he weighed in high school.

He is now a vegan.

I live on beans, legumes, vegetables, fruit. I drink a protein supplement every morning — no dairy, I drink almond milk mixed in with fruit and a protein powder so I get the protein for the day when I start the day up.

I did all this research, and I saw that 82 percent of the people since 1986 who have gone on a plant-based, no dairy, no meat of any kind, no chicken, no turkey — I eat very little fish, once in a while I’ll have a little fish — if you can do it, 82 percent of people have begun to heal themselves.

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Posted in: Nutrition

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Vitamin E and Stroke

One of the recurrent themes of science-based medicine is that any medical intervention that can plausibly cause physiological benefit can also plausibly cause physiological harm.  There is no such thing as “it can’t hurt.” Sometimes the risk may be minuscule – but we should never assume that it is zero. Being “natural” or “holistic” or being blessed with some other alleged marketable virtue does not affect the risk vs benefit calculation of an intervention.

Vitamins are an excellent example. There is widespread sentiment that vitamins are harmless, and that supplementing with vitamins is therefore a no risk-possible benefit scenario. It is certainly reasonable to conclude from the evidence that vitamins (at usual supplemental levels) are low risk, compared to many other types of medical interventions. High doses, or megadoses, of vitamins, however, risk toxicity and this risk increases with the dose.

But even at sub-toxic doses vitamins should not be assumed to be risk free. This is especially true when we take a public health perspective – what is the net effect of large scale supplementation on the population? A new meta-analysis looking at the net effects of Vitamin E supplementation on stroke risk reinforces this caution.

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Posted in: Herbs & Supplements, Nutrition

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High Fructose Corn Syrup: Tasty Toxin or Slandered Sweetener?

The perils of fructose:

High fructose corn syrup (HFCS) has, over the past few decades, gradually displaced cane and beet sugar as the sweetener of choice for soft drinks, candy and prepared foods. In recent years, there have been a growing number claims that HFCS is a significant health risk to consumers, responsible for obesity, diabetes, heart disease and a wide variety of other illnesses. 

In fact, there are large amounts of experimental data supporting the claims that high levels of fructose in the diet can cause hyperlipidemia (high levels of fats — triglycerides primarily — in the blood), obesity and insulin resistance and may lead to cardiovascular disease and type 2 diabetes (for a good recent review, see [1]). A high-fructose diet is thought to cause hyperlipidemia (and probably visceral obesity) because fructose is preferentially “sent”  to fatty acid synthesis and it also reduces the activity of lipoprotein lipase (for a good review, see [2]). The mechanisms by which fructose causes insulin resistance and cardiovascular disease are less clear (see, for example [3], [4] and [5]), but there is no shortage of hypotheses. Despite the fact that some of the underlying mechanisms are not clear, the evidence seems pretty solid that there are real risks to high fructose consumption.

However, the question remains — is HFCS more of a health risk than other sweeteners? Many of the sources that demonize HFCS list alternative sweeteners — cane sugar, honey, agave syrup, etc. — that they claim are healthier than HFCS, but those claims usually rest primarily on the fact that these alternatives to HFCS are “natural” rather than any actual data showing that they are safer than HFCS.  (more…)

Posted in: Nutrition, Public Health

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Germ theory denialism: A major strain in “alt-med” thought

The longer I’m in this whole science-based medicine thing, not to mention the whole skepticism thing, the more I realize that no form of science is immune to woo. To move away from medicine just for a moment, even though I lament just how many people do not accept evolution, for example, I can somewhat understand it. Although the basics of the science and evidence support the theory of evolution as the central organizing principle of all biology, much of the evidence is not readily apparent to those who don’t make it a calling to study biology, evolution, and speciation. It’s not like, for example, gravity, which everyone experiences and of which everyone has a “gut level” understanding. So, not unexpectedly, when the theory of evolution conflicts with a person’s religious beliefs, for most people it’s very easy to discount the massive quantities of evidence that undergird the theory of evolution. It’s not so easy to discount the evidence for gravity.

In many ways, medicine is similar to evolution, but the situation is possibly even worse. The reason is that much of the evidence in medicine is conflicting and not readily apparent to the average person. There’s more than that, though, in that there are a number of confounding factors that make it very easy to come to the wrong conclusion in medicine, particularly when looking at single cases. Placebo effects and regression to the mean, for example, can make it appear to individual patients that, for example, water (i.e., what the quackery that is homeopathy is) or placebo interventions (i.e., acupuncture) cures or improves various medical conditions. Add to that confirmation bias, the normal human cognitive quirk whereby all of us — and I do mean all of us — tend to remember information that reinforces our preexisting beliefs and to forget information that would tend to refute those beliefs — and, at the level of a single person or even practitioner, it’s very, very easy to be misled in medicine into thinking that quackery works. On the other hand, at the single patient/practitioner level, one can also see evidence of the efficacy of modern medicine; for example, when a person catches pneumonia, is treated with antibiotics, and recovers quickly. Regardless of whether they’re being used to demonstrate quackery or scientific medicine, because personal experience and the evidence that people observe at the level of the people they know can be very deceptive in medicine, science-based medicine, with its basic science underpinnings and clinical trial evidence, is necessary to try to tease out what actually works and what doesn’t.

Medicine does, however, have its version of a theory of evolution, at least in terms of how well-supported and integrated into the very fabric of medicine it is. That theory is the germ theory of disease, which, just as evolution is the organizing principle of biology, functions as the organizing principle of infectious disease in medicine. When I first became interested in skepticism and medical pseudoscience and quackery, I couldn’t envision how anyone could deny the germ theory of disease. It just didn’t compute to me, given how copious the evidence in favor of this particular theory is. It turns out that I was wrong about that, too.

On Friday there was a video released that provides a very clear, succinct explanation of germ theory denialism:

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Posted in: Chiropractic, Naturopathy, Nutrition, Vaccines

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Meat and Weight Contol

A new study published in The American Journal of Clinical Nutrition is reporting an association with eating meat and weight gain. This is a fairly robust epidemiological study, but at the same time is a good example of how such information is poorly reported in the media, leading to public confusion.

The data is taken from the European Prospective Investigation into Cancer and Nutrition–Physical Activity, Nutrition, Alcohol, Cessation of Smoking, Eating Out of Home and Obesity (EPIC-PANACEA) project. This is a long term epidemiological study involving hundreds of thousands of individuals, and is therefore a great source of data. We are likely to see many publications from from it. This one looked at the association of meat eating – poultry, red meat, and processed meat – with total weight.  From the methods:

A total of 103,455 men and 270,348 women aged 25–70 y were recruited between 1992 and 2000 in 10 European countries. Diet was assessed at baseline with the use of country-specific validated questionnaires. A dietary calibration study was conducted in a representative subsample of the cohort. Weight and height were measured at baseline and self-reported at follow-up in most centers. Associations between energy from meat (kcal/d) and annual weight change (g/y) were assessed with the use of linear mixed models, controlled for age, sex, total energy intake, physical activity, dietary patterns, and other potential confounders.

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Posted in: Nutrition

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The China Study Revisited: New Analysis of Raw Data Doesn’t Support Vegetarian Ideology

Over a year ago I wrote about The China Study, a book by T. Colin Campbell and his son based on a huge epidemiologic study of diet and health done in China. The book’s major thesis is that we could prevent or cure most disease (heart disease, cancer, diabetes, autoimmune diseases, bone, kidney, eye and other diseases) by eating a whole foods plant-based diet, drastically reducing our protein intake, and avoiding meat and dairy products entirely.

I noticed a number of things in the book that bothered me. I found evidence of sloppy citations, cherry-picked references, omission of data that contradicted the thesis, and recommendations that went beyond the data. I concluded:

He marshals a lot of evidence, but is it sufficient to support his recommendation that everyone give up animal protein entirely, including dairy products? I don’t think so.

The China Study involved 367 variables and 8000 correlations. I said I would leave it to others to comment on the study design and the statistical analysis, and now someone has done just that.  Denise Minger devoted a month and a half to examining the raw data to see how closely Campbell’s claims aligned with the data he drew from; she found many weaknesses and errors. (more…)

Posted in: Cancer, Nutrition

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Raw Meat and Bone Diets for Dogs: It’s Enough to Make You BARF

Some of the most rewarding interactions we have with our pets involve food. Most dogs respond with gratifying enthusiasm to being fed, and this activity is an important part of the human-animal bond. Providing food is also part of the parent/child dynamic that in many ways characterizes our relationships with our pets. Giving food is an expression of affection and a symbol of our duty of care to our pets.

Because of these emotional resonances, pet owners are often very concerned about giving their pets the “right” food to maintain health and, if possible, to prevent or treat disease. This has allowed the development of a large, and profitable commercial pet food industry that aggressively markets diets with health-related claims. This industry resembles in some ways the pharmaceutical industry. It is regulated by the FDA, and also by individual states, according to a somewhat Byzantine set of standards established by the FFDCA (the guiding document governing the FDA) and by the Association of American Feed Control Officials (AAFCO), a private organization made up primarily of state and federal feed control officials. Thanks to this regulatory structure, imperfect though it is, there is a good deal of solid science and research behind the products and claims the industry produces.
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Posted in: Nutrition, Veterinary medicine

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