Month November 2012

Quote of the day

Adele Hite, PhD MPH RD 11 Comments

As usual, Weight Maven has the scoop. She’ll point you to an excellent article by Modern Paleo that addresses the issue of why a one-size-fits-all approach–whether plant-based or paleo–isn’t going to work. I would probably not have seen this if it weren’t for her.

Weight Maven

Diana Hsieh has a great read over on Modern Paleo on “three major obstacles” — the value of health, individual differences, and the science of nutrition — that make it difficult to categorize essential vs optional paleo principles:

Of course, we can define a paleo diet, because it means something definite. We can also identify the general principles of a paleo approach to health … That’s crucial for doing paleo well, I think.

Yet to think of some of these principles as universally “essential” versus universally “optional” would be a mistake. Instead, they should stand in our minds as “more or less important for me.”

Do read the whole post! BTW, I’ve been in my new digs for a week and a half and hope to be back to a regular posting schedule fairly soon. Thanks for your patience.

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Not Just Science: How nutrition got stuck in the past

Adele Hite, PhD MPH RD 37 Comments

Nostalgia for a misremembered past is no basis for governing a diverse and advancing nation.

David Frum

The truth is that I get most of my political insight from Mad Magazine; they offer the most balanced commentary by far. However, I’ve been very interested in the fallout from the recent election, much more so than I was in the election itself; it’s like watching a Britney Spears meltdown, only with power ties. I kept hearing the phrase “epistemic closure” and finally had to look it up. Now, whether or not the Republican party suffers from it, I don’t care (and won’t bother arguing about), but it undeniably describes the current state of nutrition. “Epistemic closure” refers to a type of close-mindedness that precludes any questioning of the prevailing dogma to the extent that the experts, leaders, and pundits of a particular paradigm:

“become worryingly untethered from reality”

“develop a distorted sense of priorities”

and are “voluntarily putting themselves in the same cocoon”

Forget about the Republicans. Does this not perfectly describe the public health leaders that are still clinging blindly to the past 35 years of nutritional policy?  The folks at USDA/HHS live in their own little bubble, listening only to their own experts, pretending that the world they live in now can be returned to an imaginary 1970s America, where children frolicked outside after downing a hearty breakfast of sugarless oat cereal and grown-ups walked to their physically-demanding jobs toting homemade lunches of hearty rye bread and shiny red apples.

Remember when all the families in America got their exercise playing outside together—including mom, dad, and the maid? Yeah, me neither.

So let me rephrase David Frum’s quote above for my own purposes: Nostalgia for a misremembered past is no basis for feeding a diverse and advancing nation.

If you listen to USDA/HHS, our current dietary recommendations are a culmination of science built over the past 35 years on the solid foundation of scientific certainty translated into public health policy. But this misremembered scientific certainty wasn’t there then and it isn’t here now; the early supporters of the Guidelines were very aware that they had not convinced the scientific community that they had a preponderance of evidence behind them [1]. Enter the first bit of mommy-state* government overreach. When George McGovern’s (D) Senate Select Committee came up with the 1977 Dietary Goals for Americans, it was a well-meaning approach to not only reduce chronic disease, a clear public health concern, but to return us all to a more “natural” way of eating. This last bit of ideology reflected a secular trend manifested in the form of the Dean Ornish-friendly Diet for a Small Planet, a vegetarian cookbook that smushed the humanitarian and environmental concerns of meat-eating in with some flimsy nutritional considerations, promising that a plant-based diet was the best way to feed the hungry, save the planet, safeguard your health, and usher in the Age of Aquarius.  This was a pop culture warm-fuzzy with which the “traditional emphasis on the biochemistry of disease” could not compete [2].

If you listen to some folks, the goofy low-fat, high-carb, calories in-calories out approach can be blamed entirely on this attempt of the Democrats to institutionalize food morality. But, let’s not forget that the stage for the Dietary Guidelines fiasco was set earlier by Secretary of Agriculture Earl Butz, an economist with many ties to large agricultural corporations who was appointed by a Republican president. He initiated the “fencerow to fencerow” policies that would start the shift of farm animals from pastureland to feed lots, increasing the efficiency of food production because what corn didn’t go into cows could go into humans, including the oils that were a by-product of turning crops into animal feed. [Update: Actually, not so much Butz’s fault, as I’ve come to learn, because so many of these policies were already in place before he came along. Excellent article on this here.]

When Giant Agribusiness—they’re not stupid, y’know—figured out that industrialized agriculture had just gotten fairydusted with tree-hugging liberalism in the form of the USDA Guidelines, they must have been wetting their collective panties. The oil-refining process became an end in itself for the food industry, supported by the notion that polyunsaturated fats from plants were better for you than saturated fats from animals, even though evidence for this began to appear only after the Guidelines were already created and only through the status quo-confirming channels of nutrition epidemiology, a field anchored solidly in the crimson halls of Harvard by Walter Willett himself.

Between Earl Butz and McGovern’s “barefoot boys of nutrition,” somehow corn oil from refineries like this became more “natural” than the fat that comes, well, naturally, from animals.

And here we are, 35 years later, trying to untie a Gordian knot of weak science and powerful industry cemented together by the mutual embarrassment of both political orientations. The entrenched liberal ivory-tower interests don’t want look stupid by having to admit that the 3 decades of public health policy they created and have tried to enforce have failed miserably. The entrenched big-business-supporting conservative interests don’t want to look stupid by having to admit that Giant Agribusiness, whose welfare they protect, is now driving up government spending on healthcare by acting like the cigarette industry did in the past and for much the same reasons.

These overlapping/competing agendas have created the schizophrenic, conjoined twins of a food industry-vegatarian coalition, draped together in the authority of government policy. Here the vegans (who generally seem to be politically liberal rather than conservative, although I’m sure there are exceptions) play the part of a vocal minority of food fundamentalists whose ideology brooks no compromise. (I will defend eternally the right for a vegan–or any fundamentalist–to choose his/her own way of life; I draw the line at having it imposed on anyone else–and I squirm a great deal if someone asks me if that includes children.)  The extent to which vegan ideology and USDA/HHS ideology overlap has got to be a strange bedfellow moment for each, but there’s no doubt that the USDA/HHS’s endorsement of vegan diets is a coup for both. USDA/HHS earns a politically-correct gold star for their true constituents in the academic-scientific-industrial complex, and vegans get the nutritional stamp of approval for a way of eating that, until recently, was considered by nutritionists to be inadequate, especially for children.

Like this chicken, the USDA/HHS loves vegans—at least enough to endorse vegan diets as a “healthy eating pattern.”

But if the current alternative nutrition movement is allegedly representing the disenfranchised eaters all over America who have been left out of this bizarre coalition, let us remember that, in many ways, the “alternative” is really just more of the same. If the McGovern hippies gave us “eat more grains and cereals, less meat and fat,” now the Republican/Libertarian-leaning low-carb/primaleo folks have the same idea only the other way around—and with the same justification.  “Eat more meat and fat, fewer grains and cereals;” it’s a more “natural” way to eat.

As counterparts to the fundamentalist vegans, we have the Occupy Wall street folks of the alternative nutrition community—raw meaters who sleep on the floor of their caves and squat over their compost toilets after chi running in their Vibrams. They’re adorably sincere, if a little grubby, and they have no clue how badly all the notions they cherish would get beaten in a fight with the reality of middle-Americans trying to make it to a PTA meeting.

How paleo might look from the outside.

To paraphrase David Frum again, the way forward in food-health reform is collaborative work, and although we all have our own dietary beliefs, food preferences, and lifestyle idiosyncrasies, the immediate need is for a plan with just this one goal: we must emancipate ourselves from prior mistakes and adapt to contemporary realities.

Because the world in which we live is not the Brady Bunch world that the many of us in nutrition seem to think it is.

Frum makes the point that in 1980, when the Dietary Guidelines were first officially issued from the USDA, this was still an overwhelmingly white country. “Today, a majority of the population under age 18 traces its origins to Latin America, Africa, or Asia. Back then, America remained a relatively young country, with a median age of exactly 30 years. Today, over-80 is the fastest-growing age cohort, and the median age has surpassed 37.” Yet our nutrition recommendations have not changed from those originally created on a weak science base of studies done on middle-aged white people. To this day, we continue to make nutrition policy decisions on outcomes found in databases that are 97% white. The food-health needs of our country are far more diverse now, culturally and biologically. And another top-down, one-size-fits-all approach from the alternative nutrition community won’t address that issue any more adequately than the current USDA/HHS one.

For those who think the answer is to “just eat real food,” here’s another reality check: “In 1980, young women had only just recently entered the workforce in large numbers. Today, our leading labor-market worry is the number of young men who are exiting.” That means that unless these guys are exiting the workforce to go home and cook dinner, the idea that the solution to our obesity crisis lies in someone in each American household willingly taking up the mind-numbingly repetitive and eternally thankless chore of putting “real food” on the table for the folks at home 1 or more times a day for years on end—well, it’s as much a fantasy as Karl Rove’s Ohio outcome.

David Frum points out that “In 1980, our top environmental concerns involved risks to the health of individual human beings. Today, after 30 years of progress toward cleaner air and water, we must now worry about the health of the whole planetary climate system.” Today, our people and our environment are both sicker than ever. We can point our fingers at meat-eaters, but saying we now grow industrialized crops in order to feed them to livestock is like saying we drill for oil to make Vaseline. The fact that we can use the byproducts of oil extraction to make other things—like Vaseline or livestock feed—is a happy value-added efficiency in the system, no longer its raison d’etre. Concentrated vertical integration has undermined the once-proud tradition of land stewardship in farming. Giving this power back to farmers means taking some power away from Giant Agribusiness, and neither party has the political will to do that, especially when together they can demonize  livestock-eating while promoting corn oil refineries.

If we all just stopped eating meat, then we wouldn’t have to plant so much corn, right? Right?

And it’s not just our food system that has changed: “In 1980, 79 percent of Americans under age 65 were covered by employer-provided health-insurance plans, a level that had held constant since the mid-1960s. Back then, health-care costs accounted for only about one 10th of the federal budget. Since 1980, private health coverage has shriveled, leaving some 45 million people uninsured. Health care now consumes one quarter of all federal dollars, rapidly rising toward one third—and that’s without considering the costs of Obamacare.”  That the plant-based diet that was institutionalized by liberal forces and industrialized by conservative ones is a primary part of this enormous rise in healthcare costs is something no one on either side of the table wants to examine. Diabetes—the symptoms of which are fairly easily reversed by a diet that excludes most industrialized food products and focuses on meat, eggs, and veggies—is the nightmare in the closet of both political ideologies.

David Frum quotes the warning from  British conservative, the Marquess of Salisbury, “The commonest error in politics is sticking to the carcass of dead policies.”

Right now, it is in the best interest of both parties to stick to our dead nutrition policies and dump the ultimate blame on the individuals (we gave you sidewalks and vegetable stands–and you’re still fat! cry the Democrats; we let the food industry have free reign so you could make your own food choices–and you’re still fat! cry the Republicans). It’s a powerful coalition, resistant to change no matter who is in control of the White House or Congress.

What can be done about it, if anything? To paraphrase Frum once again, a 21st century food-health system must be economically inclusive, environmentally responsible, culturally modern, and intellectually credible.

We can start the process by stopping with the finger-pointing and blame game, shedding our collective delusions about the past and the present, and recognizing the multiplicity of concerns that must be addressed in our current reality. Let’s begin by acknowledging that—for the most part—the people in the spotlight on either side of the nutrition debate don’t represent the folks most affected by federal food-health policies. It is our job as leaders, in any party and for any nutritional paradigm, to represent those folks first, before our own interests, funding streams, pet theories, or personal ideologies. If we don’t, each group—from the vegatarians to folks at Harvard to the primaleos—runs the risk of suffering from its own embarrassing form of epistemic closure.

Let’s quit bickering and get to work.

**********************************************************

*This was too brilliant to leave buried in the comments section:

“Don’t you remember the phrase “wait til your father gets home”? You want to know what the state is? It’s Big Daddy. Doesn’t give a damn about the day to day scut, just swoops in to rescue when things get out of hand and then takes all the credit when the kids turn out well, whether it’s deserved or not. Equates spending money with parenting, too.”–from Dana

So from henceforth, all my “mommy-state” notions are hereby replaced with “Big Daddy,” a more accurate and appropriate metaphor.  And I never metaphor I didn’t like.

References:

1. See Select Committee on Nutrition and Human Needs of the United States Senate. Dietary Goals for the United States. 2nd ed. Washington, DC: US Government Printing Office; 1977b. Dr. Mark Hegsted, Professor of Nutrition at Harvard School of Public Health and an early supporter of the 1977 Goals, acknowledged their lack of scientific support at the press conference announcing their release: “There will undoubtedly be many people who will say we have not proven our point; we have not demonstrated that the dietary modifications we recommend will yield the dividends expected . . . ”

2. Broad, WJ. Jump in Funding Feeds Research on Nutrition. Science, New Series, Vol 204. No. 4397 (June 8, 1979). Pp. 1060-1061 + 1063-1064. In a series of articles in Science in 1979, William Broad details the political drama that allowed the “barefoot boys of nutrition” from McGovern’s committee to put nutrition in the hands of the USDA.

Not Just Science: Nutrition & Politics

Adele Hite, PhD MPH RD 42 Comments

Now that food–along with religion and politics–has joined the list of things you don’t talk about with friends, I thought I’d do my post-Election day best to offend everyone equally by highlighting just how political food and nutrition is these days.

I like to try to pass myself off as generally apolitical (on principle, I refuse to vote straight-ticket anything—but it could be I’m just a control freak who likes filling in all the bubbles myself). If forced to confess, underneath it all I’m a bleeding-heart liberal who wants to save trees and whales and who tends to blame the world’s ills on old white dudes (even—or especially –the one I’m married to).

But there’s another subtlety (and don’t tell my bleeding-heart liberal friends or they won’t invite me to anymore parties): I’d vote for ANYONE who was serious about fixing our food-health system, but—politically-speaking—who is going to do that?

Restructure subsidies, agricultural insurance, and agricultural financing to support small farmers rather than giant agribusiness? Who would do this? Democrats like feeding the excess corn, wheat, and soy commodities to the hungry people in America who are getting fatter and sicker by the minute as a result (It’s healthy!). Republicans like the big businesses that control those commodities. Everyone says they care for small farmers but no one does anything about it.

Federal nutrition program foods: plenty of soybean oil, corn syrup, gluten, and sugar, with a little arsenic thrown in for good measure

Modify food safety regulations to take into account size and type of operation? Democrats are all about protecting the public and regulating industry, but they are also all about “protecting” the public from the raw milk that those stupid Americans are stupid enough to drink. Republicans are more likely to support the dairy industry–the folks with the vested interest in outlawing raw milk–but also more likely to say the government shouldn’t be telling stupid Americans what they should and shouldn’t drink.

Somebody needs to tell Michelle that “moving more” makes kids hungry more; nothing wrong with that, but they’re not gonna “eat less” as a result.

End the one-size-fits all dietary recommendations? Thank you Michelle Obama for giving renewed vigor to the physiology-defying “eat less, move more” concept. Thank you, giant mom-and-pop-squashing Walmart, for playing right along.

You don’t like Obamacare? You do like Obamacare? You’re both right. Health reform is a joke until we focus on preventive measures that begin with feeding everyone adequate essential nutrition, not preventing chronic disease with foods that don’t prevent chronic disease.

Republicans believe that obesity is a personal responsibility; food and lifestyle choices by the public should not be interfered with by the government. Except when it comes to whether or not the public can know what is actually in the food they choose, in which case, the right to free speech when it comes to putting “health” claims on cereal boxes becomes the right to abstain from speech when it comes to putting GMO information there.

Democrats believe that it is up to the government to intervene in the market when personal choices become a public concern. So Democrats are out to make the “healthy choice” (a phrase that is an embarrassment to true meaning of both words) the easy choice for those poor stupid fat people out there who are too lazy and gluttonous to take care of their own health, never mind that the Democrat’s idea of “healthy” and “choice”  is limited to the USDA/HHS definition of both.

Republicans support the soda industry’s desire not to be taxed. Democrats are hoping butter and meat will be taxed next.

Thank goodness for the Libertarians—who are hard at work legalizing pot so the nation can now get the collective munchies. Watch for the Democrats to insist on restricted access to McDonald’s for those with medical marijuana prescriptions, while the Republicans fight for Monsanto’s right to patent all cannabis seeds grown anywhere ever by anyone. That backyard plot of weed will only be legal for about ten minutes before the Democrats start regulating the fun out of it and the Republicans hand everyone’s right to get stupid over to ConAgra.

Meanwhile, the rich get richer, the poor get fatter and sicker, and we all—rich and poor and middle-class alike—waste precious time, money, and attention on nutrition recommendations that support ideology and industry and do little for our nation’s very real health crisis. Politicians like Nixon and Clinton have undermined the nation’s ability to believe that any politicians can be trusted;  advice from the USDA/HHS, Ornish, and Atkins have done the same for nutrition. It’s a wonder we don’t all turn on, give in, and pig out.

Why Race Doesn’t Matter in Nutrition Policy

Adele Hite, PhD MPH RD 5 Comments

This is the first of a series looking at what does and doesn’t matter when it comes to nutrition policy. When I started out on this adventure, I thought that science would give me the answers to the questions I had about why public health and clinical recommendations for nutrition were so limited. Silly me. The science part is easy. But policy, politics, economics, industry, media framing, the scientific bureaucracy, cultural bias—now that stuff is crazy complicated. It’s like an onion: when you start peeling back the layers, you just want to cry. I am also honored to say that this post is part of the Diversity in Science Carnival on Latino / Hispanic Health: Science and Advocacy

When we began investigating relationships between diet and chronic disease, we didn’t pay much attention to race. The longest-running study of the relationship between dietary factors and chronic disease is the Framingham Heart Study, a study made up entirely of white, middle-class participants. Since 1951, the Framingham study has generated over 2 thousand journal articles and retains a central place in the creation of public health nutrition policy recommendations for all Americans.

More recent datasets—especially the large ones—are nearly as demographically skewed.

The Nurses’ Health Study is 97% Caucasian and consists of 122,000 married registered nurses who were between the ages of 30 and 55 when the study began in 1976. An additional 116,686 nurses ages 25 – 42 were added in 1989, but the racial demographics remained unchanged.

The Health Professionals’ Follow-up Study began in 1986, as a complementary dataset to the Nurses’ Health Study. It is 97% Caucasian and consists, as the name suggests, of 51, 529 men who were health professionals, aged 40-75, when the study began.

The Physicians’ Health Study began in 1982, with 29, 071 men between the ages of 40-84. The second phase started in 1997, adding men who were then over 50. Of participants whose race is indicated, 91% are Caucasian, 4.5% are Asian/Pacific Islander, 2% are Hispanic, and less than 1% are African-American or American Indian. I have detailed information about the racial subgroups of this dataset because I had to write the folks at Harvard and ask for them. Race was of such little interest that the racial composition of the participants is never mentioned in the articles generated from this dataset.

Over the years, these three mostly-white datasets have generated more journal articles than five of the more diverse datasets all put together.* These three datasets, all administered by Harvard, have been used to generate some of the more sensationalist nutrition headlines of the past few years–red meat kills, for instance–with virtually no discussion about the fact that the findings apply to a population–mostly white, middle to upper middle class, well-educated, health professionals, most of whom who were born before the atomic bomb–to which most of us do not belong.

Shift in demographics in past 50 years;
predicted shift in next 50 years

Although we did begin to realize that race and other characteristics might actually matter with regard to health (hence the existence of datasets with more diversity), we can’t really fault those early researchers for creating such lopsided datasets. At that point, not only was the US more white than it is now, scientific advances that would reveal more about how our genetic background might affect health had not yet been developed. We had not yet mapped the human genome; epigenetics (the study of the interaction between environmental inputs and the expression of genetic traits) was in its infancy, and biochemical individuality was little more than a glimmer in Roger Williams’ eye.

Socially, culturally, and I think, scientifically, we were all inclined to want to think that everyone was created equal, and this “equality” extended to how our health would be affected by food. Stephen Jay Gould’s 1981 book, The Mismeasure of Man, critiqued the notion that “the social and economic differences between human groups—primarily races, classes, and sexes—arise from inherited, inborn distinctions and that society, in this sense, is an accurate reflection of biology.” In the aftermath of the civil rights movement, with its embarrassingly racist behavior on the part of some representatives of the majority race and the heartbreaking violence over differences in something as superficial as skin color, it was patently unhip to suggest that racial differences were anything more than just skin deep.

But does that position still serve us now?

In the past 35 years, our population has become more diverse and nutrition science has become more nuanced—but our national nutrition recommendations have stayed exactly the same. The first government-endorsed dietary recommendations to prevent chronic disease were given to the US public in 1977. These Dietary Goals for Americans told us to reduce our intake of dietary saturated fat and cholesterol and increase our intake of dietary carbohydrates, especially grains and cereals in order to prevent obesity, diabetes, heart disease, cancer, and stroke.

Since 1980, the decreases in hypertension and serum cholesterol—health biomarkers—have been linked to Guidelines-directed dietary changes in the US population [1, 2, 3, 4].

“Age-adjusted mean Heart Disease Prevention Eating Index scores increased in both sexes during the past 2 decades, particularly driven by improvements in total grain, whole grain, total fat, saturated fatty acids, trans-fatty acids, and cholesterol intake.” [1]

However, with regard to the actual chronic diseases that the Dietary Guidelines were specifically created to prevent, the Dietary Guidelines have been a resounding failure. If public health officials are going to attribute victory on some fronts to Americans adopting dietary changes in line with the Guidelines, I’m not sure how to avoid the conclusion that they also played a part in the dramatic increases in obesity, diabetes, stroke, and congestive heart failure.

If the Dietary Guidelines are a failure, why have policy makers failed to change them?

It is not as if there is an overwhelming body of scientific evidence supporting the recommendations in the Guidelines. Their weak scientific underpinnings made the 1977 Dietary Goals controversial from the start. The American Society for Clinical Nutrition issued a report in 1979 that found little conclusive evidence for linking the consumption of fat, saturated fat, and cholesterol to heart disease and found potential risks in recommending a diet high in polyunsaturated fats [5]. Other experts warned of the possibility of far-reaching and unanticipated consequences that might arise from basing a one-size-fits-all dietary prescription on such preliminary and inconclusive data: “The evidence for assuming that benefits to be derived from the adoption of such universal dietary goals . . . is not conclusive and there is potential for harmful effects from a radical long-term dietary change as would occur through adoption of the proposed national goals” [6]. Are the alarming increases in obesity and diabetes examples of the “harmful effects” that were predicted? It does look that way. But at this point, at least one thing is clear: in the face of the deteriorating health of Americans and significant scientific evidence to the contrary, the USDA and HHS have continued to doggedly pursue a course of dietary recommendations that no reasonable assessment would determine to be effective.

But what does this have to do with race?

Maintaining the myth that a one-size diet approach works for everyone is fine if that one-size works for you—socially, financially, and in terms of health outcomes. The single positive health outcome associated with the Dietary Guidelines has been a decrease in heart attacks—but only for white people.

And if that one-size diet doesn’t fit in terms of health, if you end up with one of the other numerous adverse health effects that has increased in the past 35 years, if you’re a member of the mostly-white, well-educated, middle/upper-middle class demographic—you know, the one represented in the datasets that we continue to use as the backbone for our nutrition policy—you are likely to have the financial and social resources to eat differently from the Guideline recommendations should you choose to do so, to exercise as much as you need to, and to demand excellent healthcare if you get sick anyway. Even if you accept that these foods are Guidelines-recommended “healthy” foods, you are not stuck with the commodity crop-based processed foods for which our nutrition programs have become a convenient dumping ground.

In the meantime, low-income women, children, and minorities and older adults with limited incomes—you know, the exact population not represented in those datasets—remain the primary recipients of federal nutrition programs. Black, Hispanic, and American Indian kids are more likely to qualify for free or reduced-price school lunches; non-white participants make up 68% of the Special Supplemental Nutrition Program for Women, Infants, and Children enrollment. These groups have many fewer social, financial, and dietary options. If the food they’re given doesn’t lead to good health—and there is evidence that it does not—what other choices do they have?

When it comes to health outcomes in minorities and low-income populations, the “healthier” you eat, the less likely you are to actually be healthy. Among low-income children, “healthy eaters” were more likely to be obese than “less-healthy eaters,” despite similar amounts of sedentary screen time. Among low-income adults, “healthy eaters” were more likely to have health insurance, watch less television, and to not smoke. Yet the “healthy eaters” had the same rates of obesity as the “less-healthy heaters” and increased rates of diabetes, even after adjustment for age.

These associations don’t necessarily indicate a cause-effect relationship between healthy eating and health problems. But there are other indications that being a “healthy eater” according to US Dietary Guidelines does not result in good health. Despite adherence to “healthy eating patterns” as determined by the USDA Food Pyramid, African American children remain at higher risk for development of diabetes and prediabetic conditions, and African American adults gain weight at a faster pace than their Caucasian counterparts [7,8].

Adjusted 20-year mean weight change according to low or high Diet Quality Index (DQI) scores [8]

In this landmark study by Zamora et al, “healthy eaters” (with a high DQI) were compared to “less-healthy eaters” (with a low DQI). Everyone (age 18-30 at baseline) gained weight over time; the slowest gainers—white participants who were “healthy eaters”—still gained a pound a year. More importantly however, for blacks, being a “healthy eater” according to our current high-carbohydrate, low-fat recommendations actually resulted in more weight gain over time than being a “less healthy eater,” an outcome predicted by known differences in carbohydrate metabolism between blacks and whites [9].

Clearly, we need to expand our knowledge of how food and nutrients interact with different genetic backgrounds by specifically studying particular racial and ethnic subpopulations. Social equality does not negate small but significant differences in biology. But it won’t matter how much diversity we build into our study populations if the conclusions arrived at through science are discarded in favor of maintaining public health nutrition messages created when most human beings studied were of the adult, mostly white, mostly male variety.

Right now the racial demographics of the participants in an experimental trial or an observational study dataset doesn’t matter, and the reason it doesn’t is because the science doesn’t matter. What really matters? Maintaining a consistent public health nutrition message—regardless of its affect on the health of the population—that means never having to say you’re sorry for 35 years of failed nutritional guidance.

*ARIC – Atherosclerosis Risk In Communities (1987), 73% white; MESA – Multi Ethnic Study of Atherosclerosis (2000), 38% white, 28% African American, 12% Chinese, 22% Hispanic; CARDIA – Coronary Artery Risk Development in Young Adults (1985), 50% black, 50% white; SHS – Strong Heart Study (1988), 100% Native American; BWHS – Black Women’s Health Study(1995), 100% black women.

References:

1. Lee S, Harnack L, Jacobs DR Jr, Steffen LM, Luepker RV, Arnett DK. Trends in diet quality for coronary heart disease prevention between 1980-1982 and 2000-2002: The Minnesota Heart Survey. J Am Diet Assoc. 2007 Feb;107(2):213-22.

2. Hu FB, Stampfer MJ, Manson JE, Grodstein F, Colditz GA, Speizer FE, Willett WC. Trends in the incidence of coronary heart disease and changes in diet and lifestyle in women. N Engl J Med. 2000 Aug 24;343(8):530-7.

3. Fung TT, Chiuve SE, McCullough ML, Rexrode KM, Logroscino G, Hu FB. Adherence to a DASH-style diet and risk of coronary heart disease and stroke in women. Arch Intern Med. 2008 Apr 14;168(7):713-20. Erratum in: Arch Intern Med. 2008 Jun 23;168(12):1276.

4. Briefel RR, Johnson CL. Annu Rev Nutr. 2004;24:401-31. Secular trends in dietary intake in the United States.

5. Broad, WJ. NIH Deals Gingerly with Diet-Disease Link. Science, New Series, Vol. 204, No. 4398 (Jun. 15, 1979), pp. 1175-1178.

6. American Medical Association. Dietary goals for the United States: statement of The American Medical Association to the Select Committee on Nutrition and Human Needs, United States Senate. R I Med J. 1977 Dec;60(12):576-81.

7. Lindquist CH, Gower BA, Goran MI Role of dietary factors in ethnic differences in early risk of cardiovascular disease and type 2 diabetes. Am J Clin Nutr. 2000 Mar; 71(3):725-32.

8. Zamora D, Gordon-Larsen P, Jacobs DR Jr, Popkin BM. Diet quality and weight gain among black and white young adults: the Coronary Artery Risk Development in Young Adults (CARDIA) Study (1985-2005). American Journal of Clinical Nutrition. 2010 Oct;92(4):784-93.

9. Hite AH, Berkowitz VG, Berkowitz K. Low-carbohydrate diet review: shifting the paradigm. Nutr Clin Pract. 2011 Jun;26(3):300-8. Review.