Surprisingly, most of the questions I get through emails about “skepticism” ask about the science or myths in popular diet fads. It’s clear that there are a lot of websites, pundits, and websites with pundits who think that changing your diet is the most important thing in the world. Eat this to make your immune system strong. Don’t eat that because it causes cancer. But do eat this because it reduces your risk of cancer. Eat this. Don’t eat that. Drink this. Eat more of that.
My thoughts have always been that the human physiology is amazingly resilient, and as long as you have no chronic diseases, there is nothing one can do that will make the situation much better or much worse. Yes, maintaining levels of certain nutrients, such as vitamins C and D, iron, and others, are critical, but in the modern world, it’s almost impossible to miss out on those micronutrients. Yes, we should limit fats and “sugars”. But the thing is human physiology is complex, so marathoners eat lots of carbohydrates, and they are mostly healthy. It all depends.
And as I’ve mentioned, you’re not going to prevent or cure cancer with supplements (or presumably foods that are rich with those nutrients). Antioxidants don’t really help prevent cancer. Soy won’t stop certain types of cancer. Nor will certain foods make you lose weight. Most of these beliefs about foods, health and weight loss are based on either a boatload of anecdotal evidence, or use very preliminary laboratory research, make a leap of faith, and assume that laboratory evidence is equivalent to clinical evidence. Then, when the gold standard of research, a randomized clinical trial is done, the results generally show nothing. And in some cases, the negative effect is with the supplement or food.
Last year, I wrote an article about how to critically analyze pseudoscience and misinformation to get at the scientific evidence which may help you accept or reject something you might read on the internet, even if it appeared to be accurate. On Facebook, Twitter and many internet sites (including Wikipedia), there is an amazing tendency of individuals to accept what is written as “the truth” without spending the effort to determine if what is written is based on accurate science. Twitter, of course, limits itself to 140 characters, which means you either have to click on a link to get more information, or just accept that the 140 characters are factual. And if you can make a complex scientific argument in 140 characters, I’m impressed.
Facebook is filled with false memes on just about everything from politics to medicine. The anti-vaccination crowd fills Facebook with their amusing and highly inaccurate memes. For more than a year, there have been dozens of photos of bananas with a few words that some Japanese scientists claim that ripe bananas have high levels of “tumor necrosis factor“, so eat bananas to cure cancer and maintain a healthy immune system. Facebook is famous for these things, little pictures with a few words, no sources of the information, and broad conclusions. Eat bananas. Cure cancer. And people share them with a click of the button and move on to the next cute cat picture. It’s really the lazy person’s way of learning. Although who doesn’t enjoy the cute cat pictures?
(more…) «Despite the meme on Facebook,…»
Food additives are one of the most passionate issues amongst people who eat (which would be everyone). High fructose corn syrup. Salt. Sugar. Trans fats. Polysorbate 80. Some of the angst caused by these additives is that they have scary chemical names. Obviously the “low fructose corn syrup” has got to be better? Right?
But the one food additive that will bring fear to the minds of all consumers of food is MSG. How many times have you been to a Chinese restaurant where they put up signs with NO MSG ADDED. Just so you know, unless that restaurant isn’t using soy sauce (one of the major components of nearly all Chinese food flavorings), the amount of MSG in your Kung Pao Chicken is still quite high, because that soy sauce has more MSG in it than could possibly be added by a shaker of MSG.
MSG has no taste by itself, but it is used by many cooks as a flavor enhancer, improving and enhancing the flavor of almost any food at lower concentrations. The taste that is enhanced by MSG is different than the standard sour, sweet, bitter and salt flavors–it is called “umami,” which also is enhanced by substances like soy sauce. It’s the savory flavor that one finds that is different from the older “four tastes” that chefs used to consider. The flavor enhancing quality of MSG is not well understood, but it’s possible that humans evolved the pleasurable taste of umami as a result of natural selection favoring those who enjoy eating high quality protein foods.
MSG has been used as a flavor enhancer for several thousand years. It is one of the key components of many Asian cuisines, especially Japanese who have extracted MSG from kelp for centuries. The Romans used a sauce called garum, made from fermented fish, that was used instead of more expensive salt. In fact, MSG can be used to mask bad flavors, such as spoiled meat, just like salt.
Organic foods have been increasingly popular these days moving from local co-ops and farmer’s markets to large retail chains that specialize in organic foods (such as Whole Foods) to general large retail chains who dedicate portions of their produce sections to organic produce. Even dairy and meat sections of most supermarket chains have sections that contain organic products.
So what are organic foods? They are usually crops, meat or other animal products (milk, cheese, honey) which have been produced without the use of synthetic pesticides and fertilizers, as well as genetic modification and certain preservation techniques such as food irradiation. Also the meats and animal products are produced without the use of antibiotics and growth hormones. Organic farming was pioneered in the early part of the 20th century based on the unproven idea that chemical pesticides and fertilizers supposedly had a negative effect on flavors and nutritional values of foods. Over the years, organic farming has grown into a huge business based on the supposed health and flavor benefits, but also on the the potential benefits that organic agriculture may have on the environmental impact of agricultural chemicals. In addition, there is a lot of concern about the persistence of pesticides on our food sources.
(more…) «Organic foods–are they healthier? Are…»
There has been a belief that has been promoted over the years that very low calorie diets can promote lifespan. It was based on a 1934 research study from Mary Crowell and Clive McCay, at Cornell University, who observed that laboratory rats fed a severely reduced calorie diet, while maintaining micronutrient levels, would result in lifespans of up to twice as long as control groups. Their findings were later repeated by Roy Walford, and his student Richard Weindruch, through a series of experiments with mice. In 1986, Weindruch reported that restricting the caloric intake of laboratory mice proportionally increased their life span compared to a group of mice with a normal diet. The calorie-restricted mice also maintained youthful appearances and activity levels longer and showed delays in age-related diseases. The results of the many experiments by Walford and Weindruch were summarized in their book, The Retardation of Aging and Disease by Dietary Restriction.
(more…) «Calorie restricted diets and the…»
Here we go again. The popular press gets ahold of a scientific study, misinterprets it, and runs a scary story. Of course, it’s much worse if the scientific study published in a respected journal seems to also misinterpret the study. As I mentioned before, a true skeptic needs to critically analyze whatever is written in the press by going to the original study whenever possible; but what happens if that study requires some critical analysis? Well, I never said it was easy. If you want easy, denialism is really easy!
So back to the eggs. All across the news during the past week or so, you probably saw a story that eating egg yolks cause arteriosclerosis, a chronic condition in which an artery wall thickens as a result of the accumulation of fatty materials such as cholesterol. Some people may have already believed that anecdotally, but a new article published in Atherosclerosis, Egg yolk consumption and carotid plaque, concluded that,
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.
(more…) «Eggs and your arteries–yolk or…»
Lately, I’ve had some interesting conversations with my friend Cathy, who is an artist and designer, about a whole raft of topics in medicine and science. She proclaims she has no scientific background, but she’s intensely curious about science and about what I write, so what else could a blogger want? Recently, we were discussing what constituted a good diet. I was trying to cut through what was myth and what was science, but sometimes it can be difficult to do so. My thoughts have always been that the human physiology is amazingly resilient, and as long as you have no chronic diseases, there is nothing one can do that will make the situation much better or much worse. Yes, maintaining levels of certain nutrients, such as vitamins C and D, iron, and others, are critical, but in the modern world, it’s almost impossible to miss out on those micronutrients.
(more…) «Eating like our great ape…»
Like monosodium glutamate (MSG), the additive that everyone avoids, except there is absolutely no evidence that it does anything to anyone, high fructose corn syrup (HFCS) has evolved to become the current pariah of the food industry. Even the name sounds a bit chemical, with that “high fructose” leading you to believe it has to be bad. But is it?
That’s where we need to look at the science, because the answers to the questions are quite complicated and quite simple.
Pat Summitt, probably one of the greatest basketball coaches ever, has stepped down as the coach of the University of Tennessee’s women’s basketball team. She announced that she had early-onset Alzheimer’s disease (AD) in August 2011, and she had coached the 2011-12 season, but today, as a result of the disease, she resigned. During her career, she won 8 NCAA Division 1 Women’s Basketball Championships, a record that is almost impossible to comprehend. Her reputation and success is the envy of college sports.
Early onset AD is usually defined as a diagnosis before the age of 65. Early onset AD may occur in individuals as young as their 30′s (very rare), but with most diagnoses in patients in their 50′s. Summitt was diagnosed at the age of 58 (and without knowing everything, she might have had symptoms earlier), so the age of onset is not unusual.
(more…) «Early onset Alzheimer’s disease ends…»
In science, there is nothing more annoying than a pseudoscientific myth that is propagated to the point where everyone believes it’s a fact. For some odd reason, foods are the center of the pseudoscience universe. Eat organic. Avoid GMO (genetically modified) crops. High fructose corn syrup will kill you. Keep salt off of your food. Don’t eat this. Don’t eat that. Drink this. Don’t drink that. Yet, where is the science? Are organic foods really healthier for you? Will GMO foods harm you?
Of all the annoying myths, there’s one that is the most bothersome. MSG, or monosodium glutamate, gets the most exposure as an evil additive to foods. Yet, what is the evidence? Does it really do anything?
(more…) «MSG-fussing about nothing»