What breastfeeding and the failed cholesterol recommendations have in common: weak science

weak

Oops! Their bad.

Remember how the government said fat and cholesterol were dangerous to your health? Never mind.

As Nina Teicholz explains in an NYTimes Op-Ed (The Government’s Bad Diet Advice):

For two generations, Americans ate fewer eggs and other animal products because policy makers told them that fat and cholesterol were bad for their health. Now both dogmas have been debunked in quick succession.

First, last fall, experts on the committee that develops the country’s dietary guidelines acknowledged that they had ditched the low-fat diet. On Thursday, that committee’s report was released, with an even bigger change: It lifted the longstanding caps on dietary cholesterol, saying there was “no appreciable relationship” between dietary cholesterol and blood cholesterol. Americans, it seems, had needlessly been avoiding egg yolks, liver and shellfish for decades. The new guidelines, the first to be issued in five years, will influence everything from school lunches to doctors’ dieting advice.

She asks the obvious question: how did experts go so wrong?

The answer is that the government placed too much reliance on population based studies:

But even the most rigorous epidemiological studies suffer from a fundamental limitation. At best they can show only association, not causation. Epidemiological data can be used to suggest hypotheses but not to prove them.

Instead of accepting that this evidence was inadequate to give sound advice, strong-willed scientists overstated the significance of their studies.

Aaron Carroll addresses the same issue in today’s Upshot column in the NY Times:

For decades, many dietary recommendations have revolved around consuming a low percentage of your daily calories from fat. It has been widely thought that doing so would reduce your chance of having coronary heart disease. Most of the evidence for that recommendation has come from epidemiologic studies, which can be flawed.

Use of these types of studies happens far more often than we would like, leading to dietary guidelines that may not be based on the best available evidence.

And although we have finally learned the error of our ways regarding fat and cholesterol, we are aggressively making the same mistake when it comes to the diet of infants.

The evidence on which breastfeeding recommendations are based is no better than that on which the cholesterol recommendations were based.

The science is extremely weak, contradictory and plagued by confounding variables. Despite this, we are promoting breastfeeding as every bit as important to good health and long life as limiting dietary cholesterol and fat. Indeed, we are going farther, with government attempts to cajole and shame women who choose to formula feed, and dangerous hospital policies like the oxymoronic Baby Friendly Hospital Initiative which, in direct defiance of everything we know about babies suffocating and falling out of hospital beds, promotes 24 hour rooming in of infants, giving exhausted, potentially sedated new mothers little choice but to keep their babies in bed with them.

There were many scientists and physicians who questioned the dietary fat and cholesterol guidelines over the past decades, arguing that the scientific evidence simply did not justify sweeping dietary recommendations, but their voices were drowned out by those who insisted that we could improve the health of the American public by telling them what to eat. Everyone “knew” restricting fat and cholesterol was good for you, and scientific evidence that didn’t comport with what everyone “knew” was ignored.

The exact same thing is happening at this very moment with breastfeeding recommendations. Everyone “knows” that breastfeeding makes children smarter, healthier, thinner, less likely to developed the chronic diseases of old age. Except that’s NOT what the scientific evidence shows. The scientific evidence shows that for full term infants in first world countries, the ONLY health benefits are a minor reduction in incidence of colds and diarrheal illness in the first year of life. That it.

As Carroll notes:

It is frustrating enough when we over-read the results of epidemiologic studies and make the mistake of believing that correlation is the same as causation… In reviewing the literature, it’s hard to come away with a sense that anyone knows for sure what diet should be recommended to all Americans.

I understand people’s frustration at the continuing shifts in nutrition recommendations. For decades, they’ve been told what to eat because “science says so.” Unfortunately, that doesn’t appear to be true. That’s disappointing not only because it reduces people’s faith in science as a whole, but also because it may have cost some people better health, or potentially even their lives.

He’s right.

We’ve made a terrible mistake with dietary recommendations promoting low fat and low cholesterol diets; we went far ahead of what the science showed and we ignored any science that did not support what we “knew”.

We’re making the exact same mistake by promoting breastfeeding recommendations based on weak science.

If we learn anything from the fiasco on fat and cholesterol recommendations it should be this:

Our recommendations on breastfeeding should reflect what the scientific evidence actually shows, not what we think we “know.”

  • SilverHazel

    I’ll keep avoiding liver…… Eggs yolks? No way.

  • me

    You know what they say – science progresses one funeral at a time.

  • Robin Frees

    I agree with your assessment of research when it comes to cholesterol and nutrition we now know that cholesterol is important Matt eating healthy fat is essential for good health mineral absorption sex hormones. However evaluating the promotion of breastfeeding and human milk for human babies is rather short sighted. Human milk contains an abundance of cholesterol necessary for proper brain development and formula contains is zero cholesterol formula also contains no like pace to break down the facts and then make them readily available for functioning in the human body in addition formula does not have anybeneficial microflora which is also abundant in human milk this contributes to the colonization the infant. And contributes a massive amount report to the infant’s digestive system as well as the immune system.so as you can see there are many reasons to promote the use of human milk for human babies. The baby friendly hospital initiative promotes the protection of breastfeeding for the women who choose to breastfeed after education is provided. rooming in is promoted safely. And preparation of infant formula is provided for all mothers who choose to bottle feed. So please do your research before commenting such things and become part of the solution not part of the problem.

    • She isn’t being “part of the problem”, we’re mad about people being told that breastfeeding is the only correct solution and that formula is for emergencies only. We disagree and are tired of the judgmental attitudes as well as misinformation being spread about immunity and vaguely defined “toxins”, to the point of mothers being advised to actually underfeed their infants or accept the breastmilk of a stranger whose body obviously isn’t making milk for that baby.

      Breastfeeding is supported here. I’ve seen many visitors with questions about improving their breastfeeding experience who are given not only advice from both professionals and people with personal experience, but ongoing emotional support as well. That’s true not only of breastfeeding, but other pregnancy and child rearing issues as well.

      Before commenting, please do read the context of articles before pointing fingers. Nowhere is breastfeeding or the promotion of it being judged negatively.

  • Sue

    I understand and agree with the analogy, but there are many reasons to question Nina Teicholz’s work. Many are outlined here:
    https://thescienceofnutrition.wordpress.com/tag/teicholz/

    The most recent well-conducted meta-analyses (Mozaffarian’s team) show that saturated fat reduction DOES reduce coronary risk, so long as the energy deficit isn’t replaced with refined carbodhyrates like sugar. There is also good evidence that replacing saturated fat with polyunsaturates, in an appropriate omega 3 to omega 6 PUFA ratio, reduced coronary risk, but PUFA supplements don’t.

    Certainly we now have more sophisticated information about LDL vs HDL cholesterol, and the genetics of inherited hypercholesterolaemia, which is independent of dietary intake.

    SOrry – just had to rant about Teicholz – there is so much pseudo-science in the anti-sugar high-fat movement, which sees balance and moderation as evil concepts. End of rant.

    • Francesca Violi

      So this correlation between a high fat rate in the diet and high blood
      cholesterol rate, where does it come from? Do you knwo if researchers have some
      hipoteses to explain it?

      • Sue

        Francesa – it’s thought to be due to the build up of plaque inside coronary arteries.

        • Francesca Violi

          Yeah, I mean, if fat doesn’t cause plaques directly, why do they think these plaques occur in populations with a high fat rate consumption? Maybe people who eat lots of animal fat also tend to disregard healthy lifestyle in other areas, like eating too much, smoking, drinking, not exercising, not monitoring their blood values and pressure on a regular basis?

    • Paula

      That is quite an interesting and damning review, thanks for posting it!

      I also found this article on that blog very interesting: https://thescienceofnutrition.wordpress.com/2014/04/21/fat-in-the-diet-and-mortality-from-heart-disease-a-plagiaristic-note/

      One author misinterprets some research studies on fat and heart disease, and a whole bunch of other authors copy that same misinterpretation without ever going back to the original research.

      • Sue

        That’s a common pathway, Paula. There are so many people on the ”fructose is poison” bandwagon because of some poor understanding of the physiology. Many don’t have the knowledge to question the explanations being offered.

    • Michelle

      I agree, understand the analogy but I see the assertion as suspect and there is no change to that cholesterol is a risk factor for CHD. Also saying they said things like “bad for health”, rather what was recommended that some things be eaten in limited amounts and to change to lean meat products etc in order to lower the risk. I don’t think this changes things an awful lot, and it’s long been recognised that there are more factors that apply than dietary fat, like lifestyle, weight, smoking habits and exercise.

  • Amazed

    OT: Today, I tasted stevia for the very first time in my life (usually, it’s either sugar or bitter for me). Cocoa balls with stevia chocolate. Lovely!

    Who the hell thinks it would make a baby come out? CPMs, that’s who. Remember the idiots who crowdcounseled Christy Collins? They suggested stevia for naturally inducing Danielle.

    • demodocus’ spouse

      Goodness knows walking didn’t induce my labor when my sib and I wandered all over the zoo 3 days before my due date, no matter what people suggest!

      • Amazed

        Goodness knows but the CPMs don’t! And Gavin Michael paid the price. God, Danielle and Michael are so brave.

        • demodocus’ spouse

          amen. Old wives’ tales and superstitions are not good science. (We took the trip because it was her first time in the area and the zoo is pretty cool, and it’s hard for my pedestrian self to get there..)

    • I thought the stevia was supposed to regenerate the amniotic fluid.

      • Amazed

        Right, I got the wrong idiocy.

  • Froggggggg

    Good to see you mention the cholesterol/low-fat thing – I was actually wondering what everyone’s thought on this were. I’ve been looking into it for a while, knowing full well (from reading this blog for several years) that my own limited research may have a confirmation bias and that I’m not qualified to interpret the data. 😉 But I grew up in an European country where people eat quite a lot of (saturated) fat, yet have one of the lowest rates of heart disease, so the “avoid fat at all cost” message was always foreign to me and the carb overload in our diets seemed counter-intuitive (keeping in mind of course that moderation is still important and that you don’t need to put butter on your pizza or cream on your cereal, like someone I know used to do!). I don’t think the realisation that fundamental errors may have been made has filtered through here in Australia yet. I guess it’ll take time. I know some people have been fighting the Heart Foundation to amed their guidelines, but for now they are still pushing low-fat, high-carb and rather artifical foods as “healthier options”. I’m often surprised to see their “tick” on products I’d consider junk foods (though on their website they’ve at least acknowledged that the link between dietary cholesterol and blood cholesterol is small). I’ve actually been avoiding getting my cholesterol checked because the last thing I want is to find myself fighting with a doctor or dietitian telling me to eat less fat – in reality I probably eat too many carbs and should up my fat and protein intake. A friend of mine who has high cholesterol due to a thyroid condition still gets the low-fat talk all the time…

    It’ll be interesting to see what happens re. breastfeeding recommendations.

  • And I’ll extend the silliness to what is said with respect to planned birth mode. We lump outcomes for emergency and planned cesareans and do little to correct for the many confounding factors. As a result, there’s limited data on “planned birth mode” and outcomes – but there’s no shortage of physicians and others who feel comfortable denying maternal request cesareans.
    Further, most of the maternal health reports seem to focus on physical health and fail to integrate psychological health. It would be interesting to see if women giving birth at “baby friendly” hospitals have higher rates of PND…that’s a study I’d like to see…

    • Jen

      I was having a discussion about this with an NP friend of mine. She told me she was surprised to hear my son and I were both healthy and happy after our CS since thats not what most women report. She said the data shows signficant risks for complications in newbors with a CS delivery. I asked her if the data she was analyzing had factored in emergency C-Sections, prior prenatal care, maternal health etc. She said it had looked at just planned but I’m very skeptical. I have not found any studies showing CS as unsafe for newborns that didnt confound the data by including emergent CS in the study. Can any of you speak to this? I would like to know what the real data shows. Thanks!

      • Young CC Prof

        Probably the best place to look is planned repeat c-sections, since most of those are not emergencies. http://www.ahrq.gov/research/findings/evidence-based-reports/vbacup-evidence-report.pdf

        This review found a perinatal death rate of 0.5 per 1000 for elective repeat c-section in term babies versus 1.3 per 1000 for trial of labor after cesarean. A good look at morbidity begins on page 127 (it’s a very long report!) and basically says that transient tachypnea of the newborn is more common with elective c-section, but some more serious problems like meconium aspiration or need for resuscitation are more common with trial of labor.

      • Sue

        Cesarean-born babies have a higher rate of TTN (transient tachypnoea of the newborn – ie temporary fast breathing), which often results in a short NICU stay for observation, but sigificantly lower rates of birth injuries.

        The supporting evidence has been posted here before.

        • Jen

          Thanks! That helps explain it for me.Not at all scientific, but I had several friends that opted for vaginal births that were due arround the same time as me. There were 5 of us and 3 of the normal vaginal deliveries ended in a long NICU stay along with the need for a cooling blanket and IVs. 1 healthy vaginal and I was a healthy planned CS. I just honestly havent heard anyone tell a horror planned CS story while Ive heard lots of horror vaginal ones where either mom or baby was severly injured.

    • Daleth

      They don’t lump them together in the UK, and recently a huge study (over 2 million births) was published there that showed women having a planned pre-labor CS had a lower death rate than women who went into labor (about 3/4 of whom delivered vaginally and 1/4 by emergent CS, per British statistics–their CS rate is around 25%).

      http://www.telegraph.co.uk/news/uknews/1584671/Women-choosing-caesarean-have-low-death-rate.html

      • That is because of some very sensible women calling for clarity in the information – I wish Canadian data was similarly organized.

  • moto_librarian

    It is really hard to stop feeling like it’s wrong to eat more fat after hearing for years that it is the enemy. I have hereditary high cholesterol, and I was having a very hard time shedding baby weight. I started limiting my carbs and eating more fat and protein. I am losing weight, I don’t have blood sugar crashes, and most importantly, my cardiac bloodwork was the best it’s been in years.

    • Sarah1035

      I think you still have to view the reversal still in the context of a diet with adequate fiber and an appropriate amount of calories. I’m 5’3, if I add bacon, cheese and sauted shrimp on everything I eat it won’t be great for my weight or health. They are still calorie dense foods and I can’t eat unlimited quantities. I think people hear the reversal and think “ok I can eat a pound of bacon and a three egg omelette for breakfast everyday” when that still won’t be a healthy thing to do. I still can’t eat a 3000 calorie daily diet, but it doesn’t matter as much the make up of my 1800 calories a day (when I’m not pregnant/lactating).

      • moto_librarian

        Oh, I agree! I am cutting calories too, but I am surprised at how much easier it is to do that when eating more fat and protein. I can eat around 1600 calories a day and not feel hungry constantly.

        • Sarah1035

          I’m just concerned my triple bypass/stroke surviving father will read the headlines and go nuts instead of getting the message that it’s ok to add some bacon to the bean soup instead of it making it vegan and fat free.

          • A long time ago a dietician told me that she advises most of her patients to weigh portions according to specific guidelines rather than try to eliminate food from the diet. The surest way to get someone to obsess about any food is to instruct the patient not to eat it. Calories will be reduced if the portion sizes are controlled.

            This was certainly true of me, after my diagnosis of type 2 diabetes. I ONLY wanted to eat carbs, rather than the balanced diet I’d been eating previously.

      • Who?

        I agree that portions are key. I’ve never counted calories or eaten low fat options-they always have a weird texture and often are sweeter than I prefer-but I do manage portions fairly keenly and that seems to work for me in maintaining a healthy weight.

        Some protein at each meal-whether it’s nuts, cheese, egg, meat, pulses or whatever-keeps me going to next meal time much better than a pile of carbs.

        • High carbs will result in hyperinsulinemia, so you feel hungry all the time, as insulin production exceeds food intake.

          • Sue

            True at the extremes, but carbohydrates in the form of whole grains and starch vegetables are part of a healthy diet.

    • Are you nuts

      What percentage of calories from carbs are you eating per day? My nutritionist has me eating 50% from carbs and I’m so hungry!!

      • Mishimoo

        I’ve found that mixing lean proteins with complex carbs helps me feel satiated.

        • Sue

          The evidence on satiety shows that protein is the best nutrient for satiety.

          The problem with the low-fat message is that many food producers substituted sugar into their low-fat products.

          We have always known that excess added sugar and other processed carbohydrates aren’t healthy. Plant-based whole foods seem to be good choices, with lean protein and some fat.

          There is still evidence that reducing saturated fat reduces the coronary risk, UNLESS you replace the energy gap with refined carbohydrates.

          I’ve read up on this stuff because I’m constantly arguing physiology with the ”fructose is poison” people. Certainly, gallons of soft drink sweetened with HFCS aren’t healthy, but, within a nutritionally and energy-balanced diet, sugar isn’t ”toxic”.

          • Mishimoo

            I’ve been reading about it for the same reason! Also because there’s a family history of obesity and type II diabetes, and I’d rather not deal with that.

            “Plant-based whole foods seem to be good choices, with lean protein and some fat.” – this is pretty much how I eat because I enjoy it, but I have the time, energy, and inclination to cook from scratch. I also have the motivation as it keeps my gut happy (I have IBS symptoms) and I have a household of picky eaters.

      • Adjective

        Carb-heavy meals make me ravenous a couple hours later. I try to make most of my meals based around protein + veggie, it keeps me full much longer.

        • SuperGDZ

          Carbs induce satiety faster than fat (leptin response). Fat prolongs satiety for longer. For me it makes sense to include more healthy fat (together with a moderate amount of protein and a small amount of carbs) in my main meals, and more healthy carbs in my between-meal snacks.

      • moto_librarian

        I find that 20-30% from carbs works well for me. The carbs I do eat are coming from vegetables and milk.

    • Samantha06

      I’m so glad to hear this too! I’m following the same plan, higher fat, more protein and less carbs, other than complex carbs like veggies. I feel so much better! I’m going for my bloodwork tomorrow and I’m hoping it’s made a difference…

  • Ash

    OT:
    ” She’s [ Jennifer Ramirez-Vasquez, a 17 year old] graduating high school a year early and already has a summer job
    lined up as a breastfeeding consultant at a local hospital.”

    It’s crazy that a hospital would hire this person to be a breastfeeding consultant. How can she possibly have completed training and education to be a professional in this field?

    http://www.theatlantic.com/health/archive/2014/12/whats-behind-the-unintended-pregnancy-epidemic/383937/

    • NoLongerCrunching

      I think it depends on her job description. If by “consultant” they mean a peer-counselor who can help other teen moms be successful breastfeeding, then great. She probably knows more about the challenges her peers face than a 40-year-old IBCLC who stayed at home and breastfed with all the breastpumps and LC home visits that money could buy. If they mean that she will be responsible for problematic situations like babies who are not gaining weight or are in the NICU, then I agree that’s crazy.

  • MegaMechaMeg

    I feel like what they have in common is an intuitive leap that was not necessarily true. It feels emotionally correct that eating more fat will put more cholesterol into your blood, and it feels right that the naturally produced infant food would be the best thing to give a baby but the first conclusions are not necessarily the correct ones. Fat can be healthy for you and breastmilk lacks vitamin D. It is lazy science to stop at the easy answer even if it feels good.

    • Daleth

      Breastmilk also lacks vitamin K, which is why babies have to get a shot for that right after their born. (Well, they don’t HAVE to… unless you’re ok with the risk of bleeding on the brain.)

      • Vitamin K levels drop precipitously in ALL newborns immediately after birth and only return to normal levels after a week or so. The shot given at birth is to protect them until the levels rise again. Feeding may be a factor later, but not right after birth. [Or so we were taught]