Take a look at this headline from a Shape magazine online article – but I’m warning you, if you’re prone to head-bang-on-desk incidents like I am, you’d best don your helmet before continuing.

Low Carb Diet Linked to Shorter Life Expectancy

That’s the headline.  Here’s the subhead:

If your healthy diet doesn’t include breads, rice, oats, and other whole grains, you may be missing out on a huge health perk, says new science.

And here’s the opening paragraph:

Swearing off carbs may mean forgoing health perks as well: People who ate more whole grains throughout their lives lived longer than those who didn’t, reports a new study in the JAMA Network Journals.

Better eat your bread and other grains, because a low-carb diet is linked to an early death.  That’s the takeaway message.  So obviously, the study being reported by the Shape magazine writer compared low-carb diets to diets rich in whole grains, right?

Wrong.  The study wasn’t about low-carb diets at all.  The headline and the opening paragraph are both complete nonsense.  Hardly a week goes by when I don’t see some goof in the media misinterpret a study (often with help from the researchers), but I ignore most of those articles these days simply because they’re so common.

But this article … wow … I found myself asking the same question I often ask when politicians give speeches:  Is this goofball knowingly dishonest, or just plain stupid?

So let’s put on our Science For Smart People hats and ask some questions about the study that prompted the Shape reporter (and others, no doubt) to conclude that a low-carb diet is linked to shorter life expectancy.

Q: Is this a clinical study or an observational study?

A: It’s an observational study.  Actually, researchers dug data out of two ongoing observational studies.  Here’s a quote from the study abstract:

We investigated 74,341 women from the Nurses’ Health Study (1984–2010) and 43,744 men from the Health Professionals Follow-Up Study (1986–2010), 2 large prospective cohort studies.

I’ve written about those studies before.  The Reader’s Digest version is that they’re based on occasional food questionnaires, which are notoriously unreliable.  Whenever I see a new analysis of the same old data from either one of these studies, I know it’s time to roll my eyes and walk away.  Move along folks, nothing to see here.  But for the sake of argument, let’s assume food questionnaires are reliable and observational studies actually tell us something useful.

Q: What was the actual difference?

A:  Well, you can refer to the abstract for the details, but here’s what got the researchers and members of the media all excited:

After multivariate adjustment for potential confounders, including age, smoking, body mass index, physical activity, and modified Alternate Healthy Eating Index score, higher whole grain intake was associated with lower total and CVD mortality but not cancer mortality…. We further estimated that every serving (28 g/d) of whole grain consumption was associated with a 5% lower total morality or a 9% lower CVD mortality, whereas the same intake level was nonsignificantly associated with lower cancer mortality.

So people eating whole grains had lower mortality.  Which leads to the next question …

Q:  Compared to what?

A:  Well, from the headline in Shape magazine online, you’d think researchers compared diets rich in whole grains to low-carb diets.  But like I said before, that’s not the case.  All this data shows is that people who ate more whole grains were less likely to die prematurely.  So … if a person eats more whole grains, wouldn’t that mean he or she is eating less of something else?  Which leads us to ask …

Q: If A is linked to B, could it be because of C?

A:  That’s the $64,000 question.  And the answer in this case is almost certainly yes.  Whole grains are associated with better health outcomes, but that’s because people who eat whole grains usually choose them over refined grains.  This study was conducted at Harvard, which trumpeted the results in the media and promoted the idea that there’s something especially health-enhancing about whole grains.  Here’s a quote about the study from a Harvard press release:

“This study further endorses the current dietary guidelines that promote whole grains as one of the major healthful foods for prevention of major chronic diseases,” said Qi Sun, assistant professor in the Department of Nutrition and senior author of the study.

Wow, so it turns out the government dietary guidelines are correct!  We just proved it here in our government-funded study!  (The NIH funded the study, according to the same press release.)  People who ate more whole grains lived longer, so that proves whole grains — in and of themselves — are good for you.

Uh-huh.  But here are some quotes from a different Harvard press release, commenting on earlier data extracted from the same two observational studies:

Refining wheat creates fluffy flour that makes light, airy breads and pastries. But there’s a nutritional price to be paid for refined grains. The process strips away more than half of wheat’s B vitamins, 90 percent of the vitamin E, and virtually all of the fiber. It also makes the starch easily accessible to the body’s starch-digesting enzymes.

A growing body of research shows that returning to whole grains and other less-processed sources of carbohydrates and cutting back on refined grains improves health in myriad ways.

Eating whole instead of refined grains substantially lowers total cholesterol, low-density lipoprotein (LDL, or bad) cholesterol, triglycerides, and insulin levels. Any of these changes would be expected to reduce the risk for cardiovascular disease.

More recent findings from this study (the Nurses’ Health Studies I and II) and the Health Professionals Follow-Up Study suggest that swapping whole grains for white rice could help lower diabetes risk: Researchers found that women and men who ate the most white rice—five or more servings a week—had a 17 percent higher risk of diabetes than those who ate white rice less than one time a month.

In other words, the supposed magic of whole grains comes down to them being a somewhat better choice than refined grains that jack up blood sugar, triglycerides, insulin, etc.  That tells us absolutely nothing about the health effects of whole grains vs. no grains.

The researchers noted that “replacing” one serving per day of red meat with whole grains was also associated with lower mortality.  I put “replacing” in quotes because people in these studies don’t check a box that says I am now swapping one serving of red meat for one serving of whole grains in my daily diet.  Those daily servings are the result of number-crunching by the researchers.  Their conclusion just means that given what they consider a “serving,” people who ate one serving less of red meat and one serving more of whole grains lived longer.

As I’ve explained before, the “red meat” in these studies most often comes in the form of pizza, burritos, deli sandwiches, hot dogs, etc. – in other words, processed meats that are served with a generous helping of white flour.  So when the researchers inform the media that “replacing” red meat with whole grains was associated with greater longevity, it could simply be the result of comparing people who eat pizza for dinner to people who eat chicken, vegetables and brown rice for dinner.  That doesn’t tell us diddly about what would happen to your health if you swapped a steak for a plate of whole-wheat pasta.

The folks at Harvard may understand that (not that you can tell from their conflicting press releases), but the reporter from Shape magazine clearly doesn’t.  She somehow managed to interpret this study as demonstrating a link between low-carb diets and an early death, even though the data doesn’t deal with low-carb diets at all.

To illustrate the depth of the stupidity, let’s take the smoking analogy I used in Science For Smart People and extend it a bit.  Suppose we conduct an observational study of smokers and find that those who smoke filtered cigarettes have lower rates of lung cancer than those who smoke unfiltered cigarettes.  The proper conclusion is that filtered cigarettes might be a better option than unfiltered cigarettes.  It would be stupid to conclude that our study proves filtered cigarettes are good for you.

But our Shape magazine reporter took that level of stupidity a step further.  To borrow a phrase from the comedy Tropic Thunder, she went full retard.  Her headline is the equivalent of reading a press release about our observational study on smoking and then writing a headline like this:

Non-Smoking Linked To Higher Cancer Rate

Like I said, I can’t tell if she’s being intentionally dishonest or is just plain stupid.  Either way, it’s not comforting to know she writes for a major health and fitness magazine.

You may now bang your head on your desk.

60 Responses to “Wholly Stupid Conclusions About Whole Grains”
  1. Pierre Robert Groulx says:

    I’ve been watching “Supersize vs Superskinny” lately and I’ve noticed a pattern… Usually, MOST of the diet from the obese people is pure carbohydrate, while there’s a good portion of fatty animal products (mostly processed) from ONLY A FEW of them. The show keeps making it seem like it’s mainly about the fat and calories themselves. There’s ONE episode where it mentions how the heart gets fatter from sweets, which SHOULD give everyone a freaking hint… but no… It’s GOTTA be the meat, fat and cholesterol, right?…

    • Tom Naughton says:

      It’s an amazingly well-conditioned reflex among media health writers. I recently saw an article warning people to avoid “sweets, which are full of fat and calories.” Uh … wouldn’t “sweets” be full of something sweet? Like sugar, perhaps?

  2. Sky King says:

    I thought I’d include an Anti-Stress Kit we could all use to help us do just that (My be increased to a larger size, printed, and then cut out). :0)


  3. Michael Stedman says:

    I appreciate your sharing this article; what’s interesting is that on the same site an MD who answers questions from readers confirms that one can eat a high fat no carb diet and be perfectly healthy. If only this author and the site’s editors actually read one another’s work perhaps they’d see the contradiction! In any case, your posts are great and your movie was very good as I add my voice to the chorus of those praising you for helping change our diets to a far more healthy lifestyle. Keep up the great work!

  4. bob says:

    I think blaming or praising one individual food source is wrong . If for example eating whole grains was good , then 85% of the population would be heart disease free diabetes free etc (but we are not ) . on the other hand , if grains are bad then 85% of us would be riddled with heart disease and diabetes ( which we are not ). I think its more to do with combinations and accumulations of things that determine long or short lifespans . I mean everybody knows someone ( like my mum who lived to a healthy 82 ) who smokes 30 a day and eats crap who`s got less health problems than tea total gym freak . bottom line is we need to look at a whole wider spectrum of things before lumping down on individual food groups

    • Tom Naughton says:

      I don’t a food has to induce disease in 85% of the population to be labeled a bad choice. The smoking example is relevant — most smokers don’t get lung cancer, but that doesn’t mean smoking doesn’t cause lung cancer. Diabetes rates have been skyrocketing, even among kids, as have rates of celiac. Bad food — sugar and grains — are almost certainly to blame, even if most kids don’t end up with diabetes.

      I agree that we have to consider the diet in total.

      • bob says:

        thanks Tom . my main point was that if someone ate whole grains but ate otherwise healthily ( no processed food , plenty of healthy fats . nothing out of a packet box or tin . plenty of exercise etc etc ) would it follow that health issues would appear solely on the basis of eating the grains , keep blogging Tom , really enjoy your posts

  5. Tom Welsh says:

    You wonder whether the journalist was dishonest or just plain stupid? Unfortunately, I think the answer lies in a third direction: group-think. Even more unfortunately, that is quite compatible with honesty and reasonable intelligence. Everywhere, we see people clinging together for mutual support and reassurance – and this causes them to subscribe to the beliefs of the group. (One result, at the largest scale, can be religion).

    After all, this journalist simply copied the presumably respectable procedure of the great Ancel Keys. First, decide what you think the answer should be. Second, write it up in suitably bold prose. Third (and a long way last) consider trying to prove what you have written. (But if that step turns out to be too hard, forget it).

    As for the denunciation of low-carb diets, that’s rather like the routine denunciation of Vladimir Putin. Everyone knows that low-carb and Putin are evil, so you cannot go wrong adding yet another brick to the immense pile of communal disinformation. Journalists (and editors) may not be so strong in statistics and data analysis, but they have a very keen sense indeed of what will get them promoted, given prizes, or – on the other hand – fired and unhireable.

    • Tom Naughton says:

      I’m used to seeing journalists swallow the conventional thinking about saturated fat. But to see “whole grains linked to longer lifespan” and turn that into “low-carb diet linked to shorter lifespan” required a special brand of stupid.

    • Firebird says:

      By reading material outside the US mainstream media, I do not find Putin to be particularly evil.

  6. Troy Wynn says:

    Nice rebuttal Tom. Thanks for staying on top of this silliness. The birdseed brigade won’t stop delivering misinformation. They can’t.

  7. Tom Welsh says:

    Indeed, is this kind of “reporting” strikingly reminiscent of Orwell’s “5-minute Hate”? If you assume that it is compulsory, to remain in good standing with the group, to inveigh against Russia, Putin, or fat at least once a day – everything is explained.

  8. James H. says:

    “But this article … wow … I found myself asking the same question I often ask when politicians give speeches:  Is this goofball knowingly dishonest, or just plain stupid?”

    I understand your point but I assume politicians are guilty of dishonesty and must be proven innocent.

  9. Having worked with reporter types, I think it’s safe to go with “just plain stupid.” Perhaps “enthusiastically plain stupid.”

    I’ll always remember an example from when I was Business Manager for a local radio station. The elected bozos were in the process of passing one of Illinois’ multiple “temporary” (meaning permanent) income tax increases. Our hard-hitting, State Capital reporter popped in to ask me, “um, if they increase the income tax rate from 2.5% to 3%, how big of an increase is that?”


    “Don’t you need to use your calculator to make sure?”

    “Nope. It’s 20%.”

    “Okay, thanks.”

    A few minutes later, she was on the air authoritatively explaining the proposed twenty percent increase in the tax rate to our listeners.

    There are some good ones, of course, but you don’t find many of these folks who turned down an offer from NASA.


    • Tom Naughton says:

      And as Gary Taubes pointed out, the best and the brightest among journalists don’t usually beg to be on the health beat.

  10. Kathy in Texas says:

    This time of year always provides you with more good material than you have time for. How in the world do you choose?

  11. Boundless says:

    > … NIH funded the study …

    Thanks for turning up that fact. Funding source is, alas, now one of the first questions that has to be raised when considering alleged nutrition papers. This paper also came up on the Wheat Belly Blog:

    Ensign: It’s a Harvard paper, captain. Sensors detect Nurse’s Study references.
    Captain: Sigh, shields up.

    • Tom Naughton says:

      I’m afraid that’s the case. You want to keep your government funding, you’d best not contradict government guidelines.

  12. Kevin O'Connell says:

    Please, please do not correct the wonderful typo:
    We further estimated that every serving (28 g/d) of whole grain consumption was associated with a 5% lower total morality…
    56 g/d = total debauchery?

  13. Aaron B. says:

    By their logic, drinking a bottle of vodka every day is healthy because people who drink one bottle a day live longer than those who drink two bottles a day — and that means we can assume they’re healthier than those who drink zero bottles a day too.

  14. tony says:

    “We further estimated that every serving (28 g/d) of whole grain consumption was associated with a 5% lower total morality or a 9% lower CVD mortality”

    Thus, a pound of whole grain keeps death far away!

  15. Elenor says:

    (Or immoral.)

  16. tw says:

    My favorite line from Wheatbelly Davis is: when you stop eating onions, you stop eating onions.

    In other words no side effects.

    I think a grain study should explore the withdrawal side of the equation. The headache I had for 2 weeks was a surprise. I was pretty fit so weight loss wasn’t an issue, but the other small things, numerous small things tells me that no one promoting grain should be doing so without obstaining for at least a month and seeing how they do without, then reintroducing it.

    I think the term you are looking for here is confirmation bias. People have been selling an idea and they are wedded to it. They are emotionally invested. That’s why we keep seeing these articles. Everyone has to figure it out for themselves.

    • Tom Naughton says:

      Definitely a huge confirmation bias at work. When the government essentially pays your salary by funding your studies, you’ll want to confirm the government’s recommendations.

    • Arturo says:

      And even before such a grain study, they would have to explore (or at least admit) to the existence of withdrawal symptoms linked to grain elimination to begin with, as there is no hurry to link anything negative to wheat and grains (even to the point of reluctantly acknowledging people who suffer from Celiac disease or allergies.

      Any acknowledgement of such symptoms are always depicted in the context of being purely the fault of the diet (Low Carb Flu, Paleo Flu, Atkins Flu, etc), and seen as proof that you need to TOSS yourself back into the immaculate embrace of healthy whole grains.

  17. js290 says:

    Tom, the reason these propaganda pieces work in the mainstream media is most people simply do not have enough background to form a null hypothesis to compare these ridiculous studies and articles against. It works out great for the propaganda machine.

    We’ve all seen various internet personalities demanding citation to studies. Without a useful null, pitting one study against another amounts to not much more than mental masturbation… skeet skeet!

    Less processed whole grains sold at a higher price because of the “healthy” label. Could not have worked out better.

  18. Boundless says:

    re: Is this goofball knowingly dishonest, or just plain stupid?

    In this particular case, the writer at least has no formal journalism training. She attended a college of art and design, and got a BFA in professional writing with a minor in graphic design. Make of that what you will.

    Actual BSJ and MSJ journalists may represent a third conjecture to your rhetorical question, “… or a victim of J-school brain damage”.

    Most people mistakenly assume that journalists are still primarily focused on the old five W’s and one H (Who, What, When, Where, Why & How). They aren’t. Here’s why:

    • Tom Naughton says:

      I was a journalism/mass communications major. Many of the future journalists I met in class were “I want to save the world!” types. That means they want to become advocates, not objective reporters.

  19. Jillm says:

    Buy a glucose meter. A fat and protein meal gave me a blood glucose reading of 4.9. After a high carb meal my blood glucose was more than twice as high.

  20. Tomas Blesa says:

    Can I have two questions?
    1. Does a good study even exist? (I mean comparing grain – no-grain diet in better controlled conditions)
    2. Why people still have tendency to blame processed meats? I don’t see how grinding meat and adding some salt and spices can make this thing evil.

    • Tom Naughton says:

      I haven’t seen a controlled study on grains vs. no grains. I don’t imagine anyone is anxious to fund that one.

      There are various theories as to why processed meats might be bad — the nitrates, etc. But again, we’re talking about an association. It could simply be that people who eat more processed foods have worse health habits overall.

    • Bonnie says:

      Processed meats often have sugar in them. If one is avoiding all sugar, as I am, it should be a no-brainer to give up processed meats. Tho I’ll admit to an occasional hot dog, minus the bun.

      • Bonnie says:

        Wish I could edit my comment! Bacon is also processed, which is why I don’t have it as often as I’d like.

      • Tomas Blesa says:

        Sugar in processed meats is usually present in very small quantities (who wants sweet sausage). I make my own ham at home and I put about one teaspoon of table sugar per 2 pounds of meat. It’s nothing but this little spoon makes difference between boiled pork and ham.
        Effects of sugar intake are dose-dependent.

        Thank you Tom, Bonnie and gallier2 for answers.

        • Georgene says:

          Tomas, are you not aware of the huge demand for maple-flavored sausage, and bacon, and recipes with brown sugar glaze made with orange juice, too, all over ham?

          I am certainly no purist, but I have to thank my parents for not ever drowning meat in sugar, so it’s definitely not appealing to me. But yep, it’s definitely a thing for people nowadays. (Having said that, I’ve long had a thing for catsup and steak sauce, much to my detriment.)

          As far as whether this “reporter” is stupid or knowingly dishonest, I think there are two factors involved: 1) her editor said “you have this much space to fill with a deadline of such-and-such date; now go do it,” and 2) what could she write that would fill that space, PLUS sound controversial, but still land on the side of what the readers generally “want” to hear.

          Notice that “truth” and “facts” make no appearance in either 1) or 2).

          • Tom Naughton says:

            There is that constant need for stories. I sometimes wonder if that’s why newspapers and news sites run articles about every stupid study that comes along.

  21. Valerie Kirkland says:

    Loved everything you were saying Tom, until you used the term “she went full retard”. Not sure why you felt of all the words in the world, that is the one you picked?? You wrote this in Jan 2015. Times have changed!!
    I have 4 kids with Down Syndrome, and they and I are offended that you would use their medical condition, that we are thankful for BTW, to describe ignorant and idiotic people. By using the term, you are shown to be as ignorant as the people and the studies you write about in this article. http://www.r-word.org

    • John says:

      Valerie, context is everything. He’s not telling people with special needs that they are retarded. Now, suppose that the politicians he’s poking fun of are indeed mentally retarded… I’d say in that case that he would be a little out of line.

      Even saying something like “You’re special” has negative connotations to the mentally handicapped. It’s almost like every word can offend someone in some way. Have you ever said something that happened was “crazy”? If so, you’d be offending people with dementia and should think on your sins.

Leave a Reply