Yes, But Where’s The Evidence?posted by Julie O'Toole on November 13, 2014 at 9:32am
You may have heard me say it before: medicine is as prone to fads as the fashion industry. And worse: tightly held “truths” in medicine can be as entrenched as religious beliefs and providers will respond to being challenged with as much heat and resentment as if you had challenged their religion. Didn’t your grandmother tell you (mine did) to avoid talking politics and religion in polite society? Well… here I go anyway. And sorry for the many citations. If you’re going to talk about evidence and evidence-based medicine, you have to have citations. I actually want to talk about the use of whole milk, but let’s back up a bit and look at some other medical belief issues which I run across on a nearly daily basis, and the science or non-science behind them. These then set the stage for a discussion of milk. Everybody knows that drinking lots of water is good for you, right? Headaches are attributed to “not drinking enough”, “toxins” are believed to be “flushed out” by drinking lots of water. Appetite is believed to be suppressed, etc. You hear it all too, I’m sure. The supposed health benefits of drinking a lot of water are truisms spouted in seemingly every sports and fitness magazine and article in the country… so much so that I have heard of parents being berated by school officials for not sending their child to school with a water bottle. Puuleeze! And the evidence? Well, “everybody says so,” is about the extent of it. Drs Negoianu and Goldfarb of the Renal, Electrolyte, and Hypertension Division, University of Pennsylvania, took a look at these claims and published their findings in the Journal of the American Society of Nephrology. If you would like a more reader-friendly “translation” (disclaimer: all translations carry inherent bias and risk of misinterpretation) go to the version published in the Telegraph News . Their summary: “Scientists say there is no evidence drinking large amounts of water is beneficial for the average healthy person, and do not even know how this widely held belief came about.” Can we move past this water thing finally?! Another tightly held belief, which causes otherwise mild-mannered people to nearly come to blows, is the belief that sugar causes hyperactivity. Oh man, has this one ever been examined, over and over. For a thoughtful (and readable) discussion of how the actual evidence reveals that sugar ingestion does not cause hyperactivity in human children see this article in Yale Scientific. Or Richard Milich’s article “Sugar and Hyperactivity: A Critical Review of Empirical Findings” in which he concludes that, “most studies have failed to find any effects associated with sugar ingestion, and the few studies that have found effects have been as likely to find sugar improving behavior as making it worse. “ So can we also move past the sugar thing yet? And last but certainly not least (in my book) is a belief clung to as tightly by physicians as by grandmothers, namely that ingestion of saturated fat will cause heart attacks, “clogged arteries” and death. Decades have been defined by fear of eggs and butter. Julia Child famously refused to believe it, or rather adopted a “devil may care” attitude about her lovely French recipes (Come to think of it, were the French dying faster than everyone else?). Today there are now hundreds of cookbooks designed to help us cook “lite”, or “healthy” food, that is, food without fat, animal fat or saturated fat of any kind. As an old fashioned cook myself and one whose favorite Chinese dishes feature pork belly, boy, did I breathe a sigh of relief to read: “A meta-analysis of prospective epidemiologic studies showed that there is no significant evidence for concluding that dietary saturated fat is associated with an increased risk of CHD [coronary heart disease] or CVD [cardiovascular disease].” Finally! And the citation here is from the American Journal of Clinical Nutrition, although if you are interested in this topic you can find a tsunami of citations online by Googling the subject. And now to whole milk. My granddaughter Piper is four. Her parents are both active in their careers and she attends a preschool near her home. Knowing my daughter-in-law, this preschool was vetted and re-vetted for best quality teaching, nurturing and—yes—feeding. Apparently, though, she was surprised to learn that Piper’s school was being forced to offer kids the option of either low fat or skim milk or even chocolate milk (as long as it was “low fat”) in order to retain USDA financial subsidies. She and the owner of the pre-school challenged the wisdom of this. The teachers had wanted to offer organic whole milk in non BPA containers (glass), but had been told that if they offered anything except low-fat or non-fat white or chocolate milk or even allowed children to bring their own whole milk from home they would lose their subsidy, resulting in higher tuition costs for parents. My daughter-in-law immediately set about doing her homework to understand the issues. In an email she wrote to me : “While Piper is at a private school, they do get subsidies for the kids’ food. Her teachers told me that if they don’t abide by these guidelines they will lose their subsidy and parents will have to pay $60 more a month per child for her to afford serving the same food she is now. Or, she can no longer offer snacks and lunch and we have to bring our own!” For many young families, $60 a month is a budget breaker. Have you looked at the cost of daycare and preschool lately? It’s staggering. But that aside, what research is the USDA referencing to make this recommendation? Could this “evidence” have reached its “expired by” date, much like the above information on saturated fat? What could be fueling this belief that fat free chocolate milk is a better option for young children than full fat milk? Let me guess: the obesity epidemic. If being (or becoming) overweight tracks from childhood through adulthood, could we prevent fatness in adults by reducing children’s exposure to (and taste for) whole dairy products? Again, where is the evidence for this? A 2014 article in the Journal of Nutrition tells us: “In conclusion, our data indicate that higher dairy consumption during preadolescence does not adversely affect excess fat deposition during early adolescence. Most associations between dairy intakes and excess adiposity were inverse [my emphasis], particularly for full-fat dairy products, suggesting a protective relation. However, given the wide confidence limits of our parameter estimates, additional prospective research is warranted to examine the relation between dairy intake and obesity.” Whoops: inverse relationship! It seems that full fat dairy ingestion may actually be protective against becoming obese! OK. So there appears to be no evidence that full fat dairy makes you fat—and some evidence that it may even protect you from later obesity, but if you or I expect the government to act quickly on new science, well… don’t hold your breath. I guess Piper will be drinking water in school and whole milk at home. But how about the rest of the kids, your kids and grandkids? Who will advocate for them? Does this still widely held belief in the “health” benefits of fat free foods put them at risk? For the record, I want to end this blog stating categorically: at Kartini Clinic we believe in real food (i.e. whole grain, full fat) and have never used any other kind of dairy product for our kids except the full fat kind: à votre santé!