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Let me introduce myself. My name is Mark Sisson. I’m 63 years young. I live and work in Malibu, California. In a past life I was a professional marathoner and triathlete. Now my life goal is to help 100 million people get healthy. I started this blog in 2006 to empower people to take full responsibility for their own health and enjoyment of life by investigating, discussing, and critically rethinking everything we’ve assumed to be true about health and wellness...

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April 06, 2016

15 Reasons Not to Trust That Latest Nutritional Study

By Mark Sisson
88 Comments

Reasons Not to Trust That Latest Nutritional Study FinalNutritional studies are often the best we’ve got. Without them, we’d be plucking anecdotes from a swirling vortex of hearsay, old wives’ tales, and prejudices. Some actionable information would definitely emerge, but we wouldn’t have the broader vision and clarity of thinking offered by the scientific method. Most of them are deeply flawed, though. And to know which ones are worth incorporating into your vision of reality and which only obfuscate and further muddy the waters, you have to know what to watch out for.

Today, I’m going to discuss many of the reasons you shouldn’t trust the latest nutritional study without looking past the headlines.

1. Industry distorts the research.

Last year, Marion Nestle looked at 152 industry-funded nutrition studies. Out of 152, 140 had favorable results for the company who funded it. An earlier analysis of milk, soda, and fruit juice nutrition studies found that those sponsored by milk, soda, and juice companies were far more likely to report favorable results than independent studies. The same things happens in cardiovascular disease trials and orthopedics trials.

2. Ego distorts the research.

People become wedded to their theories. Imagine spending 30 years conducting research to support your idea that saturated fat causes heart disease. How hard will you hold on to that hypothesis? How devastating would opposing evidence be to your sense of self-worth? Your research is your identity. It’s what you do. It’s how you respond when chit chatting at cocktail parties. You’re the “saturated fat” guy. Everything’s riding on it being true.

Scientists are used to being the smartest person in their respective rooms. It’s not easy to relinquish that or admit mistakes. Heck, that goes for everyone in the world. Scientists are not immune.

3. Correlation masquerading as causation.

In day-to-day life, correlative events imply causation. You cut someone off, they honk at you. A man holds a door open, you thank him. You flip a light switch, the light turns on. We’re used to causation explaining correlations. So when two variables are presented together in a nutritional study, especially when it seems plausible (meat causes colon cancer) or reaffirms popular advice (saturated fat causes heart disease), we’re likely to assume the relationship is causal. Correlations provoke interesting hypotheses and tests of those hypotheses, but they’re very often spurious. Everything we eat is associated with cancer if we look hard enough. Does that actually tell us anything useful?

4. No control group.

If you want to know the effects of an experimental intervention, you need a group of people that don’t receive the intervention. That’s the control group. Without a control group to compare against the group that received the experimental intervention, a clinical trial doesn’t mean much. You can’t truly know that the experimental variable caused the change without it.

5. Fake controls.

The presence of a control group doesn’t make it a good study. The control group has to be a real control. Take this paper from last year claiming that oatmeal for breakfast promotes satiety. Sure, when you’re comparing oatmeal to a cornflake breakfast. It doesn’t take much to beat the satiating (non)effects of cornflakes. How would oatmeal compare to bacon and eggs, or a big ass salad, or sweet potato hash? This study doesn’t tell you that.

6. Small sample size.

The smaller the sample size, the less impressive the results. The larger the sample size, the more meaningful the results and the more likely they are to apply to the larger population. That’s why the results of n=1 self-experiments are mostly useful for the person running the experiment on themselves and less useful for others; the sample size of one isn’t enough to generalize the results.

Small sample size studies shouldn’t be ignored. They can lead to interesting questions and hypotheses that larger studies can tackle. But they shouldn’t sway public policy, scientific consensus, or your decision about what to eat and how to live.

7. Demographics.

Make sure you know who participated in the study. If you’re a Latino male of 20 years, the study on low-carb diets in post-menopausal black women may not apply to you.

8. Food frequency questionnaires (FFQ).

FFQs require people to recall their typical diet over the last year. That’s hard. Here’s a sample FFQ (PDF); see how you do trying to recall the foods you ate over the last 12 months. Suffice it to say, they aren’t very reliable. People lie. People forget. People tell you what they think you want to hear, downplaying the unhealthy stuff and overstating the healthy stuff. FFQs are probably the best option available for assessing, but they aren’t good enough.

9. The adherer effect.

Michael Eades calls it the “adherer effect.” I’ve called it the “healthy user effect.” Whatever phrase you prefer, this describes the fact that there’s “something intrinsic to people who religiously take their medicine that makes them live longer,” even if that medicine is a completely inert placebo. Perhaps they’re also more likely to heed other medical advice, like exercising regularly, getting checkups, eating healthy foods, and other behaviors that improve health which could explain some of the beneficial effects. But it’s a real thing, and it has a real effect on the results of nutritional studies.

10. Statistical significance versus clinical significance.

You see the phrase “significantly associated with” a lot in scientific papers. “Fat is significantly associated with type 2 diabetes” sounds like “dietary fat has a large effect on your risk of type 2 diabetes.” But what that phrase really means is “The association between fat and type 2 diabetes is unlikely to be a coincidence.” It says nothing about the size of the association. It doesn’t mean eating fat doubles your chance of getting type 2 diabetes. The clinical significance—the biological effect—is very likely trivial.

11. Relative risk versus absolute risk.

Papers will often talk about “the risk” of something. More often than not, that’s a relative risk. Take something like colon cancer. Though it’s the third most common cancer (and cause of cancer-related deaths), the absolute risk of developing colorectal cancer, even in old age when the risk is at its highest, isn’t exactly high. For the average 50 year old, his or her lifetime absolute risk of colorectal cancer is 1.8%. If that 50 year old has a relative with colon cancer, the absolute risk is 3.4%. Having two relatives with a history of colon cancer pushes it up to 6.9%. On the big scale of things that can kill you, colorectal cancer isn’t even in the top five.

So anything that increases the risk of colon cancer starts from that otherwise meager degree of absolute risk.

12. Nutrients versus foods.

Most nutrition studies attempt to measure the effect of specific nutrients on health outcomes. But people don’t eat palmitic acid. They eat dairy and meat. People don’t eat linoleic acid. They eat almonds, or soybean oil, or pumpkin seeds. People don’t eat glucose, fructose, resistant starch, and prebiotic fiber; they don’t even eat “carbs.” They eat cold potatoes, sweet potatoes, blueberries, wild rice. Studies that look at specific nutrients can’t tell you accurate information about the effects of foods, because foods contain far more than just single nutrients.

13. Most research is wrong.

In 2005, John Ioannidis published a paper called “Why most published research findings are false,” citing conflicts of interest, small sample sizes, insignificant clinical effects, and failures to replicate—in other words, most of the stuff mentioned in today’s post. It eventually became the most widely cited paper ever published in PLoS Medicine, and it’s still true today. Keep it in mind.

14. Journals prefer to publish and researchers prefer to submit exciting studies with strong results.

You’re more likely to have your paper published if it presents a new, exciting finding with a strong result. If two researchers run similar studies and only one gets a positive result, a journal will usually publish the “successful” study and ignore the other one. For their part, researchers are more likely to submit “successful” papers to journals. The end result is a lack of negative results, even though they’re informative and vital for accurate science to prevail.

15. We know very little.

“Blueberries improve memory.” In who? People with dementia, people who are at high risk for it? Can kids improve school performance by eating blueberries? What about college students? What if the college students are female—does that change anything?

“Nuts reduce mortality risk by 40%.” How long do you have to eat the nuts? Does the type of nut matter? Does your age affect the protective effects of nuts?

There’s too much we don’t know. There are too many variables we can’t control.

This isn’t to suggest that nutritional studies are useless. I cite and refer to them all the time. They’re often the best, most objective angle on the situation available. Like democracy, it’s the worst except for all the others. But we have to recognize and consider their limitations. Hopefully after today’s post, you’ll know what to look for.

That’s it for today, folks. Let’s hear from you. What do you think? How do you analyze a nutritional study? What do you look out for?

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88 Comments on "15 Reasons Not to Trust That Latest Nutritional Study"

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Megan
Megan
1 year 2 months ago

Informative and thought-provoking post. These sorts of issues with studies are all too often forgotten when examining a wide range of topics that the media presents us with studies about on a daily basis. People are too often easily convinced with scarcely more evidence than a flashy primetime news report or a sassy internet headline.

Groktimus Primal
1 year 2 months ago

People lie like a rug, aren’t very bright and life’s complicated. That actually makes the Primal lifestyle that much stronger. No one can make a serious argument about the past.

Hobbes
Hobbes
1 year 2 months ago

Actually the primal lifestyle is refutable. For the most part your meats, veggies and fruits are distinctly different than what people were eating 100,000 years ago.

Zach Rusk
1 year 2 months ago

First day here? ????

Old Clockguy
Old Clockguy
1 year 2 months ago
Actually, the meats, veggies, and fruits are distinctly different than what people ate just 10 years ago, I don’t recall much clamber about GMO’s and Grass Fed this and Range grazed that so there has been a lot of change in the recent past regarding what seems to be the “in” thing to talk about regarding our diets and what is “out” as “old wive’s tales” and recently proven “wrong”. I can think of many examples of both of these old time habits that have been refuted by newer theories and then re-refuted by people like Mark who know that… Read more »
GG
GG
1 year 2 months ago

Agreed, foods were much different. But besides the artificial ingredients, GMOs etc, 10,000 years of artificial selection and cultivation since the agricultural revolution has rendered many of our modern commercial fruits and vegetables nearly unrecognizable from their original form. It is nearly impossible to truly recreate a paleolithic lifestyle eating the plants that are available to us today.

b2curious
b2curious
1 year 2 months ago

Hobbes – we are aware of that. Try looking around some here. You’ll find that topic discussed periodically.

William Oscar Jones
1 year 2 months ago

The inability to re-create the Paleolithic diet is exactly why I have created my own diet (book deal, TBD, if Mark’s on the comments section, maybe he can throw me a bone). Working title: Eat the REAL Paleo Diet: Go Paleozoic. Weight loss is guaranteed, as you’ll spend most of your time searching for trilobites.

Wenchypoo
Wenchypoo
1 year 2 months ago
Nowadays, the rush to publish (anywhere–in a scientific journal or the NTY, doesn’t matter) is so great, and so many institutions rely on that “prestige” to garner more funding…so they can continue to publish studies that won’t pass scrutiny, rest on their prestige laurels, garner more funding, etc. Lather, rinse, repeat. Research, or what passes for research, has become a fund-raising machine. They think, “who cares about accuracy?” as they trade research crap for dollars to do more of the same. We’re not supposed to know the paper is (or parts of it are) bogus, and if it weren’t for… Read more »
Marge
Marge
1 year 2 months ago

That’s overly negative. Just TRY to come up with a perfect study, that is actually fundable and doable! Plenty of these researchers are doing their best. But the consumer should still approach the info with healthy skepticism.

Shary
Shary
1 year 2 months ago

There’s no such thing as a perfect study, which, IMO, makes them all pretty worthless.

Eric B
1 year 2 months ago

My favorite example of “correlation does not equal causation” was a satirical article published many years ago. If I remember correctly, the article argued for the reduction of juvenile delinquency through the ban of all tomato products, The justification was a fictional but plausible study indicating that 98% of all juvenile delinquents were known to have eaten tomatoes.

barry
barry
1 year 2 months ago
What recent study are you referring to mark? I did see a study referring to the paleo diet as being protective against heart disease and diabetes in elderly women. However the more I read into it the more it sounded like a mediterranean diet. It was only 19% saturated fat and a whopping 71% polyunsaturated fat. They didn’t specify if it was a omega 6 omega 3 dominant diet, which would tell us a lot. However the way they wrote about saturated fat it seemed they held a very conventional view on “artery clogging saturated fat”. Not exactly a view… Read more »
mario
mario
1 year 2 months ago
I saw that study too, from Sweden I believe. Your general assessment is correct that the diet followed more of a mediterranean principle than paleo principle however I would add that is was more like a grain free mediterranean diet. You should also realize there’s a few differences in the paleo an primal diets. Loren Cordain who started the official paleo diet said saturated fat needs to be under 7%. He wasn’t and really even isn’t now a fan of saturated fat. He has changed his stance from 7% to 15%, he practically doubled it but still well below the… Read more »
Stella B
Stella B
1 year 2 months ago

The study participants ate lean meat, olive and canola oil. I haven’t noticed a lot of “paleo” diets recommending canola oil.

Walter
Walter
1 year 2 months ago

Canola oil is frequently used in “Paleo” diets used by experimenters, frequently in rodent studies.

b2curious
b2curious
1 year 2 months ago

barry – I don’t think that Mark was referring about any specific recent study. This post is about why you shouldn’t blindly trust every new nutritional study that comes along, which we already knew. He then goes into what to look for. This advice is good for the “latest nutritional study” whether it came out last week, today, next week, or a year from now.

Jessica
1 year 2 months ago

This is quite timely, as I just had a conversation about a recent study on the benefits of corn oil on heart health. My first question was ‘Who funded/sponsored the study?’ My next questions were about length of study, numbers of participants, control groups, and long-term evaluation of results. Needless to say, the conversation didn’t go very well.

Beata
Beata
1 year 2 months ago

I look at the traditional diets of the cultures that are not too far from my geographical area and think long and hard. Is what they eat beneficial to me? I love the Paleo system of nutrition but Ikarians eat little meat and plenty of pulses. So, I eat some meat and some pulses (soaked, sprouted and well cooked) and observe my reaction. It works for me!

Shary
Shary
1 year 2 months ago

Good article that everyone should read. I know quite a few people who change their eating habits like they change their socks, based entirely on what the latest study indicates. It’s a knee-jerk reaction, even with intelligent persons. They assume these studies are gospel and seldom bother to question them.

eatsleepswim
eatsleepswim
1 year 2 months ago

My favorite study from the past stated that people who drank less than 2 glasses of water per day were more likely to have heart attacks. Do we think these people perhaps never exercised? And the study was funded by drinking water providers.

Brian
Brian
1 year 2 months ago
I have to be honest here, this article depresses me. This reads to me like an attempt to make the marksdailyapple community more insular and inoculate it against research that might be contrary to the themes of this blog. I truly appreciate all the information that’s been made available in this community, but this particular article pretty much reads like self-serving bull. It could be a useful article, to someone who reads it very carefully, but having 15 points about why an upcoming research article is probably wrong and then mentioning just twice that research is still pretty much our… Read more »
Clay
Clay
1 year 2 months ago
My interpretation of the post is that we need to have a critical eye to all studies because that’s all we have. That’s not a self serving contradiction, that’s a honest assessment of the situation. I don’t honestly believe all people are kind and truthful and want to do good, but I do believe that me acting as if they do is the only way to create a better society. I don’t honestly believe that the other car coming towards me in the opposite lane will always stay in their lane. However, it would be impossible to drive if I… Read more »
Susan
Susan
1 year 2 months ago
I tend to agree more with Clay’s interpretation. My personal “point 16” would be that any single study is highly likely to be wrong or flawed in some way, because that’s how science works. Someone constructs a hypothesis, develops an experiment to test said hypothesis, and publishes the results. “Hey, I tried this, and that’s what happened.” That’s the cue for other scientists studying the same subject to replicate the study & compare results. Some will succeed, some will find some flaws, and some completely demolish the original study. The cycle continues until something approaching a consensus emerges. It still… Read more »
Brian
Brian
1 year 2 months ago

I really like both of these responses to my comments. If this is how most people are reading the article, then that’s be a good thing. It’s research and followup that separates a well-founded disagreement conventional wisdom from basically a conspiracy theory. I think it’s important to keep that in mind before deciding to reject new ideas that disagree with your current position. With that in mind, I think that questioning the merits of individual studies is also an important part of new discovery.

b2curious
b2curious
1 year 2 months ago

Brian – The following comments are a direct copy and paste from my reply to barry, a few comments up. “I don’t think that Mark was referring about any specific recent study. This post is about why you shouldn’t blindly trust every new nutritional study that comes along, which we already knew. He then goes into what to look for. This advice is good for the “latest nutritional study” whether it came out last week, today, next week, or a year from now.”

Time Traveler
Time Traveler
1 year 2 months ago

The short version to viewing nutritional studies and otherwise: Take everything with a grain of salt.

The Long version: We can’t walk through life trusting no one and nothing; the better approach, would be to expect the unexpected and deal with it, one case at a time.

Derek
Derek
1 year 2 months ago

I would also add one of my favorite #16s:

Every biological process has a range of response. If 100 people follow the same diet protocol, some will lose 20 pounds and some will gain 3. If the average is 9 pounds lost, that says little about where i fall on that curve. The same goes for medication trials. The only way to know if something really works for me, and to what degree, is to try it for myself.

Colleen
Colleen
1 year 2 months ago

This is a really important point. Carb tolerance, for example, is fat going to vary widely. Some will be responders in a bad way to more saturated fat.

Marge
Marge
1 year 2 months ago

YES! When you are looking at nutrition, your own personal response is what you need to determine. Sure, that is not what you want for distilling general guidelines….

Rich
Rich
1 year 2 months ago
As a biological sciences student I am in agreement with much of this article It’s important we do meta studies and have proper peer review to make studies as useful as possible. The Cochrane Foundation is a good example of this. Some comments here suggest that we can rely on our own self experiments. However, this is equally a problem and why we do science in the first place. Right now we all operate on our prejudices, limited information that we have that generally agrees with what we already thought. Few of us change significantly based on evidence – we… Read more »
Shary
Shary
1 year 2 months ago

+1

Dan
Dan
1 year 2 months ago

These studies are a dime a dozen! Every time I hear about one I yawn. Coffee’s good for you, coffee’s bad for you and on and on!

oxide
oxide
1 year 2 months ago

I’ll add Reason #17: the time length of the study. I remember a study which “proved” that low-fat was better for weight loss than low-carb. Time of the study: 12-14 days. That’s not even long enough to get to carb flu!

Shelly
Shelly
1 year 2 months ago

Having read the post – which I agree with wholeheartedly – I am curious to know this communities thoughts on the China Study. Real or fake? Or somewhere in between?

Tanya
Tanya
1 year 2 months ago

Denise Minger debunked the China Study, google her, you’ll find her blog, it’s fascinating!

b2curious
b2curious
1 year 2 months ago

If you’ve not found it, here’s the link to Denise Minger’s take on the China Study. https://rawfoodsos.com/the-china-study/

Mat Herold
1 year 2 months ago
Perhaps the problem in research is also a lack of what Ralph Waldo Emerson call self reliance, which can also mean truth above all else. ‘A foolish consistency is the hobgoblin of little minds, adored by little statesmen and philosophers and divines. With consistency a great soul has simply nothing to do. He may as well concern himself with his shadow on the wall. Speak what you think now in hard words, and to-morrow speak what to-morrow thinks in hard words again, though it contradict every thing you said to-day. — ‘Ah, so you shall be sure to be misunderstood.’… Read more »
bill mccauley
1 year 2 months ago

Mark, I’ve been a regular reader and Primal Blueprint follower for years and I love your work; thanks. However, if you believe your quote of “We know very little” is accurate, how can you profess to be such an expert on this important and rapidly growing field of exercise and nutrition.

OctoberAmy
OctoberAmy
1 year 2 months ago
I love to read Mark’s blog for precisely the reason that he DOESNT “profess to be an expert”. He consistently presents all sides of every discussion, applies common sense, and tests every notion with a sensible approach of, “is it something mankind has eaten/done for hundreds of thousands of years? Or is this new to our genes? ” He also presents what works for him with appropriate humility and acknowledges that we are all different. I used to come here just to read about nutrition, now it’s my first stop for any subject..sleep issues, stress, plantar fasciitis, just yesterday was… Read more »
Janet
Janet
1 year 2 months ago

Bill, each point refers to a reason we should not trust ‘the latest nutritional study’. If we know very little (about that latest nutritional study), maybe we should distrust it.

Bill Varon
Bill Varon
1 year 2 months ago

Great article and I couldn’t agree more. Now let’s replace “nutritional study” with “climate study” and guess what happens?

Crickets…

Clay
Clay
1 year 2 months ago

Yes, totally the same. Millions of years of verifiable climate history combined with decades of international global research in all aspects of how this interacts with biology, chemistry, geology and physics, is totally the same as a four week study on blueberries and memory on eight senior citizens. Glad you pointed that out.

Bill
Bill
1 year 2 months ago

Keep believing it. Reason #1 will lead you to all the money behind the global cooling, errr global warming, ummm I mean the climate change scam. Now back to my 30 degree day in Michigan which used to be under a glacier before those darn prehistoric SUVs caused them to recede/advance/recede so many times. Wake up and follow the money.

Clay
Clay
1 year 2 months ago

Yes, lots of money to be made living in the arctic and studying permafrost. Same with taking core samples in swamps. Big money. Really glamorous. Total chick magnet too.

Marge
Marge
1 year 2 months ago

If you follow the money, you will immediately see that all the industries – and their lobbies – associated with fossil fuels are interested in debunking climate change. There is really no financial incentive in acknowledging the deeply depressing data.

John
John
1 year 2 months ago
Actually, though I get Clay’s drift (and enjoy the sarcastic bite), I don’t think climate change studies are off the hook of the issues Mark brings up. There were decades of international research in biology and chemistry showing saturated fat is bad for us. Yet here we are, reading Mark’s Daily Apple because we now believe all that research was wrong. And yes, there is big money behind climate change research – it is called grant money, and it is not usually granted to those swimming against the crowd. Yea, I know, not as big as big oil, but it’s… Read more »
Kit
Kit
1 year 2 months ago
We are chimps in the trees. Tell us we are causing environmental degradation and harming the earth’s human-carrying-capacity and you will get looked at quizzically and then all will leap around the trees and shout, thinking someone will take things from them. If you say the world is getting warmer, they will look at you jump around the trees in fear, thinking the sky is going to fall in, then look back at you looking for an answer to their problems and probably give you stuff to solve the problem (and take things from you whilst you are jumping around… Read more »
Bill
Bill
1 year 2 months ago
Look. The bottom line is whether you are on the left or on the right, whether we are talking about nutritional studies, climate studies, no child left behind standardized testing, gun control vs. gun freedom, whatever the study… you can be assured that whichever position is shown in a positive light, its advocates are benefiting or are financially connected to the study. Both sides – liberal/conservative. And both sides seem to accept the truth only when it’s convenient for them to do so. Mark – I’m sorry for hijacking the conversation. Your website is awesome and you are a great… Read more »
Eric
1 year 2 months ago

“Millions of years of verifiable climate history…”

Really? Records have been kept for millions of years? Then why do we question the diet of our ancestors? Surely somebody kept food logs back then too.

Clay
Clay
1 year 2 months ago
Yes. It’s called geology and biology. There are historical markers all over the planet. By examining tree rings you can tell when there we drought years. Core sample in ice a mile deep you can tell the co2 concentration in the atmosphere on any give time period. Same with ocean floor core samples. You can tell what pollutants were in the air as well. Our mountain ranges tell us what the sea level were, what was living in the ocean at the time, and how fast the continents are moving due to plate tectonics. Our coral reefs are rich with… Read more »
oxide
oxide
1 year 2 months ago

“Surely somebody kept food logs back then too.”

They did. The food logs all *said* they were eating roasted mammoth and wild kale like good little Groks, but in reality they were sneaking Toll House cookies and ice cream during Game of Thrones. :rolleyes:

Alex
1 year 2 months ago

It is possible to demonstrate everything, by tweaking statistics…

http://yetanotherblogonnutrition.blogspot.ch/2015/10/approach-to-nutrition.html

Daria Schooler, MD
1 year 2 months ago

I submitted public comments when government nutritional guidelines were being revised. My public comments were conveniently deleted from the government website. Funny how factual, honest medical science can be blocked by the dogma of the “stakeholders” in the government-agriculture-industrial complex.

Dr. Dana Leigh Lyons
1 year 2 months ago

Oh, thank you for this, Mark! So many times I have clients come to me with understandable concerns stemming from mass media hype over “the latest study.”

This list offers a wonderful, clear resource–one that will help me help others understand why study findings often (or usually) aren’t what they seem.

HeyDianne
HeyDianne
1 year 2 months ago

Actually, it seems that old wives’ tales have a longer time frame of reference and just might have a better basis of accuracy.

OctoberAmy
OctoberAmy
1 year 2 months ago

+1

wildgrok
wildgrok
1 year 2 months ago

and another +1 here

Emily
1 year 2 months ago

This is so true. I always cringe when I read about a “scientific study” using 100 or less individuals being touted as dogma. Thanks for the post Mark!

Judy Griesi
Judy Griesi
1 year 2 months ago

Yes…..thank you Dianne. The ‘old wives tales’ I grew up with turned out to be right-carrots were good for your eyes, fish was brain food, when baking, the ‘goodness’ of the cake was dependent on the number of eggs you incorporated in the batter (the more eggs the more ‘goodness’). And sweets were to be consumed as a treat, not as an every day event. Was this science lost to the annals of time?

Tom B-D
Tom B-D
1 year 2 months ago

that’s why I look to experts for diet predictions instead: http://www.newyorker.com/magazine/2016/04/04/grain-forecast
good for grins

Becky D
1 year 2 months ago
Thus the rise of n=1 self experimentation and finding what works for the individual. I like to experiment one thing at a time to see how it impacts me regardless of the promises from studies or experts. That plus a bit of understanding on how to assess an individual or study’s credibility when reading the publications. Being aware of the items you’ve listed in this post helps to start wading through the “latest thing” shoved in your face by a friend, co-worker, or client. And I think that’s extremely important. I was sent an article on how the “original paleo… Read more »
kddomingue
kddomingue
1 year 2 months ago

These are all excellent points and should all be used as criteria to judge studies and “Breaking News!” reports. I remember how flabbergasted and stunned I was, many, many years ago, to find out that, at that time, the vast majority of health studies that were being done had only men in their studies. We’re not talking about prostate studies here. We’re talking heart, lung, stroke……all things that BOTH genders get or have. Know the rationale behind excluding women? Their monthly hormonal fluctuations would screw up the data. :\

Tuba
Tuba
1 year 2 months ago

Asking the wrong research question is a problem as is misstating study elements. You read a negative study on low carb diets only to learn the rat study calls 67% of energy from carbs as “low carb” as compare to the usual 80%… and then they made up the difference with real crappy vegetable oil and blamed the results on the “low carb” diet.

Rob
Rob
1 year 2 months ago

I totally agree with the info provided. We’re very similar at some point however we are all individual in many ways.We all react in different food groups & nutritional needs. Studies & experiment can perform in many different ways. Its up to each & every one of us to see what suits us best in the long term.
Overall, its about taking responsible of our own health & well being.

Dale Mcvay
Dale Mcvay
1 year 2 months ago

Big fan of the n-1 thought….. Does it work for me?

Bob
Bob
1 year 2 months ago

Comment 2, paging Dr. Ornish, paging Dr. Dean Ornish

Marge
Marge
1 year 2 months ago
This is an excellent summary of issues with research literature. As a researcher, I constantly had to dig to find any of the details that would help to put the resulting data into context. Without knowing the conditions of a study, the data means next to nothing. In that study that seems to indicate that drinking coffee inhibits Alzheimer’s, were any of the non-coffee drinkers avoiding coffee.for reasons such as stomach sensitivity? Bladder issues? Any other tolerance issues that might indicate.minor health problems that could affect, ultimately, proneness to Alzheimer’s? In studies indicating the healthfullness of drinking red wine, are… Read more »
J L Gentry
J L Gentry
1 year 2 months ago

Good post. Unfortunately, as the “research” can lead to lucrative book deals and exposure on TV, the desire to undergo more stringent scientific review is diminished. I also think you hit an important point near the end – that research that shows negative or even neutral results usually gets tanked. Its hard to sell a million copies of a book entitled “We Aren’t Sure What You Should Eat”.

Tommylee
Tommylee
1 year 2 months ago

Not so fast J L Gentry. You may just have a million copy best seller here.

Rap
Rap
1 year 2 months ago
One could argue that n=1 is in some ways the only valid study there is. To base a science on differences between a hypothetical average person in one group and a hypothetical average person in another group, neither of whom truly exists and whose data overlap so much that one can only make probability statements about whether the differences are “real” is in some ways ludicrous. Consider for example the recent finding that there can be wide variation in how different people respond to different diets, which was touted in the media as a real breakthrough. This has for years… Read more »
Jim
Jim
1 year 2 months ago

Good debunking analysis. The obvious question, though, is can you offer scientific support for paleo/primal that avoids your 15 reasons?

Kara
Kara
1 year 2 months ago
Medical, biomedical and biological research as it is done today, it is about: the prestige of the principal investigator and the team, the funding body/company and what they are expecting from the PI and team, and the prestige of the University or organisation where said PI and team do the research. Then, it comes down to publishing and there is quite a debate about the non-reproducibility of many a study and the whole publishing arena is another can of worms. A study is supposedly to be more credible if published in a journal with a higher score. Many nutritional studies… Read more »
ob
ob
1 year 2 months ago
The article and comments make some good points. My background is in toxicology and occupational hygiene. It was Philippus Aureolus Theophrastus Bombastus von Hohenheim who said “The dose alone makes a thing not a poison.” Why any parent would inflict a total name on their offspring that is that long is beyond me So, PATB Von Hohenheim had a pen name “Paracelsus”. At the end of the day it is all about dose and response. Most of these studies really measure either associations or a qualitative relationship. Medical science overall tends to emphasise the response above the dose. That is… Read more »
Angie
1 year 2 months ago

Oh fabulous! I need to summarise this in point form, print it out, and carry it with me at all times for all those occasions when people say, ‘Meat causes cancer, all the scientific evidence says so.’

Ptolemy
Ptolemy
1 year 2 months ago

In my opinion there is a significant omission. By definition food is grown and therefore has characteristics particular to the place where it was grown (“terroir”)

Even if all 15 shortcomings could be ironed any study that concluded eating “XYZ is good for you” would mean little to me if the study participants ate XYZ grown in Arizona and I eat XYZ in Dusseldorf.

Joe
Joe
1 year 2 months ago
Really good article, interestingly I watched this interview about cholesterol last night https://www.youtube.com/watch?v=7gZt9DQqtZI What resonated with me was when Dr Krause basically says that the kind of funding structure to definitively do a proper wide ranging dietary study to put the matter of diet to bed once and for all has diminished so we may never know for some time. Lunacy really when you consider the amount of people dying from degenerative diseases year on year that they can’t put a few £/$ into a pot and work out why?? The only conclusion I draw is that there are a… Read more »
Christy
Christy
1 year 2 months ago
Jack Lea Mason
Jack Lea Mason
1 year 2 months ago

One other element is there are occasional studies that actually demonstrate conventional wisdom and status quo as incorrect. However, the scientific journal peer review staff are often are influenced by special interests and/or professional jealousy. For this reason, good information and breakthrough findings are often denied publication. This supports the observation that there is still so much we do not know but somebody may have solid evidence that is just not available through conventional channels.

Janik L.
1 year 2 months ago

Once again, corporatism infiltrate every walk of life.

I’m pro-capitalism but it’s sad to see this state of things. Its sad that we don’t know what to believe anymore

Carpenter Ken
Carpenter Ken
1 year 2 months ago

I’m 73. I’ve tried to live healthy and I am. My favorite over the years has been the discussion of eggs. News flash…eat eggs and die of a heart attack soon. The next day science has proven eggs are good for you, followed by OMG colesteral is certain death. In my opinion after all the news regarding eggs, the only way they will kill you is if you eat them without chewing first.

Vicki
Vicki
1 year 2 months ago

“nuts reduce mortality risk by 40%”

I love the studies that report increased or decreased risk of mortality. Last I heard, we all have a 100% risk of death.

abloy
abloy
1 year 2 months ago

16. You want the study to be wrong.

Come on:
6. Small sample size, 10. Statistical significance versus clinical significance, and 14. Journals prefer to publish and researchers prefer to submit exciting studies with strong results.
Statistics take into account for small sample sizes. In (6) uncertain results are bad but suddenly in (14) they are good. This list is rubbish.

Lovisa Karlsson
1 year 2 months ago

Hello Mark! Wonderful points you have discussed . I completely agree with your research work. But the fact is that we have no nutritional food in real in the market . We only have option that either we should be educated so that we can easily judge what is real and what is fake in the market. or we should contact direct to the farmer to get real organic food with full of nutrition from there.

Deb
Deb
1 year 2 months ago

Thanks, Mark, I needed that.

Thomas
2 months 18 days ago

Excellent points! the sad thing is that when a person has been wedded to their idea for a long time they know that if they waver from their position they may lose the respect they are accustomed to. It’s possible to recover from this position, but it is a long and hard road if not handled deftly.

Linda
2 months 18 days ago

So glad that we’re thing in this manner. Gives me hope for the pursuit of truthfulness.

Linda
2 months 18 days ago

Thinking in this manner?!?!

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