This is an edited version of an article on the public side of AmazingRibs.com in response to today's news on red meat.
On October 1, Bradley Johnston, PhD, an epidemiologist from Dalhousie University in Canada, published new research in the Annals of Internal Medicine produced by a team of 19 scientists from around the world. The team studied the studies on red meat and basically said the conclusion that red meat is risky is suspect because the methodology is suspect. They claimed there was no outside funding of the research and no conflicts of interest on the team.
Their reasoning? Most of the research that was used to tell us to eat less red meat was based on flawed "observational" studies, and they don’t explain the risk. How observational studies mislead us
In the world of top quality science, a team starts out with a question. They then devise experiments that might answer it. They don't know if the experiments will answer the question until they collect the data. Their experimental design always includes proper controls. That means that if they are testing the effect of a new cattle feed, they give it to half the animals and not to the others. And they select the animals carefully. Then they do many replications. This is the gold standard scientific method.
Here's the problem with dietary science: We can't take 1,000 people, divide them into two groups, feed them different diets for their entire lives or even a year, and see how it impacts their health and mortality. Or to put a finer point on it, as a researcher at the FDA told me "You can't put humans in a rat cage."
Most dietary and nutritional studies are known as epidemiological studies or observational studies. Epidemiological studies are usually based on survey data. Researchers collect information from a group of subjects carefully chosen to represent a larger population. They are then asked a bunch of questions, the data is punched into a computer, and the researchers look for correlations. For example, researchers have noticed that French people are not as obese as Americans, so they try to find out why by studying their diets and other factors. Often they find useful correlations - they drink much more wine than Americans.
Epidemiological studies are useful, but they are nowhere nearly as reliable as, physics or chemistry or other sciences that use the gold standard scientific method. Just because we have made a study of something doesn't mean we have studied it.
Here's an example. In several epidemiological studies it has been found that people who watch a lot of television are fatter than the rest of us. Therefore, one might conclude that television causes obesity, right? Perhaps it is the light emitting from TV screens? Perhaps it is invisible radiation from the screen? Electromagnetic fields? Vapors from the plastic? Subliminal mind control? Perhaps it is the flame retardants in our sofas? Perhaps we should ban television, or ration TV watching? Or could the obesity be caused by something else? Like snacking while watching? Or cravings caused by commercials? Or lack of exercise? This is a crucial, vital, truism: Correlation doesn't mean causation.
On the other hand, epidemiological studies easily proved that lowering speed limits and wearing seat belts saved lives. So they are not to be totally discounted.
Dieticians and nutritionists, supposedly experts on what is healthy and what is not, seem to have trouble agreeing on what is healthy and what is not. An article in the New York TImes in 2016 surveyed hundreds of members of the American Society for Nutrition about what they thought was healthy. For example, 53% said granola was not healthy, 39% said popcorn wasn't healthy, and 41% said pork chops were not healthy. Risk
The other complaint Dr. Johnston’s team had was with the way risk was stated, or not stated, in observational research.
For example, in October 2015 the World Health Organization (WHO) announced that processed meat was to be classified as Group 1, "carcinogenic to humans". The WHO panel says that eating about 4 slices of cooked American style bacon per day increases your odds of colorectal cancer 18%. What the heck does that mean?
Well, the Center For Disease Control (CDC) says that over a lifetime your risk of colorectal cancer is under 5%. Four slices of bacon a day will up the odds to less than 6%. And how many of us eat four slices of bacon a day for 79 years? And as bad as it is, colorectal cancer is rarely fatal.
Oh, and by the way, of the 22 scientists from 10 countries on the panel, 15 voted for the conclusions that were published and 7 disagreed or abstained. Why the significant dissent and why publish such far reaching conclusions designed to change lifestyles and damage livelihoods with a vote of only 68%?
Everything we do carries risk. There is no such thing as risk-free living. Or eating. What we need to understand is that some actions are riskier than others. By far, by a very long distance, the riskiest thing we do is get in a car. Do you buy only organic food and then use your cell phone when driving home? If you do, you are hereby authorized to eat bacon with every meal for the rest of your short life. Let's get our priorities straight. How the media, especially the internet, fails us
Much of what we consumers think we know about diet and health is wrong.
Our disconnect is the byproduct of the internet and all the half truths it tells. It is from our fear of the unknown. It is our suspicion of big business. It is our fear of illness and mortality. It is the fact that science is complex and often written in jargon that we cannot understand. It is because our BS meters are not running.
Newspaper, TV, magazine, and radio reporters are usually not well trained in the sciences and not capable of reading scientific research and translating it for the lay public. As a result, they often get it wrong, seizing on the seemingly shocking headlines touted by the PR people at the university that funded the research.
Here's a classic case: In December 2018, The BMJ, a respected medical journal, published a research project by a team led by Robert Yeh of Harvard titled "Parachute use to prevent death and major trauma when jumping from aircraft: randomized controlled trial". In the paper they report that they collected data from 23 volunteers some of whom jumped from an aircraft with a parachute and some with an empty backpack. Shockingly, they concluded "Parachute use did not reduce death or major traumatic injury when jumping from aircraft."
Whaaaaaat? Well it turns out, the aircraft were parked on the ground and the jump was only about two feet. People often read the paper's abstract and conclusions and come to a misunderstanding of the entire project without reading it thoroughly wading through the test protocols, statistical analysis, charts and graphs, and references (this paper cited Sir Isaac Newton among others). Fortunately BMJ was in on the joke and traditionally sprinkle a little humor into their Christmas issue.
If you see a recipe that says it is healthy, run. Chances are the author is just parroting the popular media, not science. Bottom line
So what's a person to do? Love food! Don't fear it! Anxiety over what you eat will probably kill you faster than anything you eat. Take what you hear from the media, from your friends, and especially from the internet, with, ahem, a grain of salt. Keep your BS meter turned on high. You doctor is not infallible, but she knows better than the TV news reporter. Before you obsess over your lunch, compare the risk of eating a bologna sandwich with putting makeup on your eyes. Or driving your car. Or putting on your makeup while driving your car. Select your food carefully, but don't give yourself an ulcer worrying about it.
If you live to 79, the average life US expectancy, and eat three meals a day, you will eat 86,505 meals. It is really doubtful that a few bologna sandwiches, an occasional hot dog or burger, or even a few bags of Cheetos will dent that. Even if you went on a bender and ate a hot dog for lunch every day for a week. If you at one hot dog a week for your entire life, that would be 4,108 hot dogs out of 86,505 meals. A pittance! Even a dietician will tell you that an occasional small bag of potato chips, a hot dog, a candy bar, a martini, or barbecue sauce with HFCS are not going to hurt you. Just don't make them mainstays of your diet.
It is probable that "Standard American Diet" (SAD) probably includes too much meat, too little vegetable, and too few whole grains and nuts. We should probably reduce our portion sizes and eat more meals without meat. We eat too many foods made in factories so we can't control what is in our meals. We should probably cook from scratch as often as possible. (Notice how I cover my butt with the word probably because what we know to be fact today is sure to be false tomorrow. Given that the nutrition and diet sciences seem to be so rudimentary, we might someday learn that one of the ingredients in Cheetos is good for you.)
And please please please, when you find a diet that works for you, don't oppress your friends with your food religion. Just swallow your tongue.
We all want a long, healthy life, but life should not be an ascetic journey of denial of pleasure so that we can arrive at the end with a perfect body. I plan to watch my diet and take everything in sensible proportion, but deny myself of no opportunity for great pleasure because of some research paper that will be invalidated in a year. As Dr. David Katz, the founding director of Yale University's Prevention Research Center has said "The cold hard truth is that the only way to eat well is to eat well."
I plan to arrive at the pearly gates with a bottle of French Burgundy in one hand and a rib bone in the other, laughing and regaling anyone within earshot with tales of how great my life was.
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