Public Health Nutrition’s Epic Fail

Mostly I just wanted to say “epic fail” because it embarrasses my kids, but then, they are always harshing on my mellow.

The stated goals of the US Dietary Guidelines are to promote health, reduce risk of chronic disease, and reduce the prevalence of overweight and obesity.

How’s that working for us?

First the good news. Cholesterol levels and hypertension have trended downwards since the creation of our first Dietary Guidelines.

It is possible that the changes in these risk factors reflect a trend that was already well underway when the Dietary Guidelines were written . . .

. . . although some folks like to attribute the changes to improvements in our eating habits (Hu et al 2000; Fung et al 2008). And btw, yes, they actually have improved with regards to the dietary recommendations set for in our Guidelines. Don’t believe me? You’re not alone. Here’s the data.

Soooooo . . . if our diets really have improved, and if those improvements have led to related improvements in some disease risk factors (because cholesterol levels and even blood pressure levels are not diseases in and of themselves, but markers—or risk factors—for other disease outcomes, like heart disease and stroke), let’s see how the Guidelines fared with regards to actual disease.

This trend is a little ironic in that cancer was, at first, one of the primary targets for nutrition reform. It was Senator George McGovern’s ire at the Department of Health, Education, and Welfare’s (now the Department of Health and Human Services) failure to aggressively pursue nutritional links to cancer that was at least part of the motivation behind giving the “lead” in nutrition to the USDA in 1977 (Eskridge 1978; Blackburn, Interview with Mark Hegsted). In fact the relationship between dietary fat and cancer had so little solid evidence behind it, the 2000 Dietary Guidelines Advisory Committee had this to say: “Because relationships between fat intake and cancer are inconclusive and currently under investigation, they are deleted.”

I guess we can then feel assured that the reason that the restrictions against fat and saturated fat are still in the Dietary Guidelines is because their relationship to heart disease isn’t inconclusive or “currently under investigation”? If that’s the case, somebody better tell these folks. So what did happen to heart disease as we lowered our red meat consumption and our egg intake, while we increase our intake of “heart-healthy” grains and vegetable oils?

Well, you’d think with all of that reduction in fat and saturated fat, plus the decrease in smoking, we’d be doing better here, but at least—well, at least for white people—the overall trend is down; for black folks, the overall trend is up.

Oops. Not so good.

Hmmm.

Oh. Well. This can’t be good. And of course, my favoritest graph of all:

I’m not sure, but it sorta kinda looks like the Dietary Guidelines haven’t really prevented much, if any, disease. Maybe we could get those guys at Harvard to take a closer look? I mean, looking at these trends—and using the language allowed with associations—you might say that the development and implementation of Dietary Guidelines for Americans is associated with a population-wide increase in the development of cancer, heart failure, stroke, diabetes, and overweight/obesity. Anyway, you might say that. I would never say that. I’m an RD.

Are there other explanations for these trends? Maybe. Maybe not.

It’s always a good idea to blame food manufacturers, but we have to remember that they pretty much supply what we demand. And in the past 30 years, what we’ve demanded is more “heart-healthy” grains, less saturated fat, and more Poofas. Yes, food manufacturers do help shape demand through advertising, but the Dietary Guidelines don’t have anything to do with that.

Oh yeah. That‘s so whack, it’s dope.

References:

Blackburn H. Interview with Mark Hegsted. “Washington—Dietary Guidelines.” Accessed January 24, 2011. http://www.foodpolitics.com/wp-content/uploads/Hegsted.pdf

Centers for Disease Control and Prevention (CDC). National Center for Health Statistics, Division of Health Interview Statistics, data from the National Health Interview Survey. http://www.cdc.gov/diabetes/statistics/prev/national/figpersons.htm. Accessed 15 August 2010.

Centers for Disease Control and Prevention (CDC). National Center for Health Statistics, Division of National Health and Nutrition Examination Surveys. Prevalence of Overweight, Obesity, and Extreme Obesity Among Adults: United States, Trends 1976–1980 Through 2007–2008. http://www.cdc.gov/NCHS/data/hestat/obesity_adult_07_08/obesity_adult_07_08.pdf

Accessed February 1, 2011.

Eskridge NK. McGovern Chides NIH: Reordering Priorities: Emphasis on Nutrition. BioScience, Vol. 28, No. 8 (August 1978), pp. 489-491.

Fast Stats: An interactive tool for access to SEER cancer statistics. Surveillance Research Program, National Cancer Institute. http://seer.cancer.gov/faststats. Accessed on 11-1-2011.

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.

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.

Morbidity and Mortality: 2009 Chart Book on Cardiovascular, Lung, and Blood Diseases. Bethesda, Md: National Institutes of Health: National Heart, Lung, and Blood Institute; 2009.

Americans don’t follow Guidelines—or do they?

One of the enduring myths of our current nutrition culture is that Americans don’t follow recommendations–have never followed them–because if we had, this obesity thing wouldn’t have happened. According to the 2010 Dietary Guidelines Advisory Committee Report, “average American food patterns currently bear little resemblance to the diet recommended in the 2005 Dietary Guidelines for Americans.”

As proof, the following figure is provided:

FIGURE 1: Americans don’t follow dietary recommendations!

It seems pretty obvious that Americans are woefully off-base when it comes to eating anything close to what the USDA and HHS have been recommending for the past thirty years. I would bet my RD certification that this figure will be shown in PowerPoints across the land to demonstrate—to the accompaniment of much hand-wringing—how we must “make the healthy choice the easy choice” for those poor, dumb Americans who will otherwise just eat themselves into obesity and ruin airplane trips for the rest of us.

Aside from the fact that Americans are being evaluated on whether or not they follow the Guidelines, rather than whether or not the Guidelines are actually appropriate, there are some serious “truth in advertising” issues going on with this figure.

First, note the data collection time points: National Health and Nutrition Examination Surveys from 2001-2004, and 2005-2006. And the fun begins . . .

1) The figure shows that we eat too many calories from SoFAS. But this concept was not part of the Guidelines until the 2010 Dietary Report, the report that contains this figure. In other words, Americans are being held to standards that hadn’t even been created yet.

2) The saturated fat “cut-off” is based on a 7% of calories. The recommended limit for saturated fat at the time the data were collected and at the time this document was written is 10% of calories, not 7%.

3) The standards for whole grain consumption given in the Guidelines that the public would be familiar with when the data were collected were pretty vague: “Choose a variety of grains daily, especially whole grains” (from the 2000 Dietary Guidelines). I don’t know how this translates into an absolute amount of whole grains that Americans don’t consume.

4) The report that contains this figure (the 2010 Dietary Guidelines Advisory Committee Report) indicates that added sugars should be less than 25% of calories. Current research indicates that added sugar consumption by Americans is around 16% of total calories (Welsh et al, 2010, JAMA). According to this figure, Americans consume 242% more added sugars than recommended. Another mystery.

5) In the fine print, it says that the sodium cut-off is based on the recommended Adequate Intake (AI) amount. The AI amount is a “goal for adequate intake,” and, as such, is more of a floor than a ceiling. The AI amount is currently set at 1500 mg of sodium for adults. On the other hand, the Dietary Guidelines that were in effect at the time the data were collected set sodium recommendations at 2400 mg (2000 DGs) and 2300 mg (2005 DGs) per day.

Americans don’t follow the Guidelines–but the standards being used in a number of cases aren’t even part of the Guidelines?

Here’s a different perspective on whether or not Americans are following dietary recommendations:

FIGURE 2: Or do they? Black lines represent lower limits of Acceptable Macronutrient Distribution Range (AMDR) given in the Dietary Guidelines; red lines designate upper limits of AMDR.

Since 1980, Americans have been told to increase their carbohydrate consumption and reduce their fat intake. Since 1980, we’ve done just that. American’s consumption patterns fall within the recommended AMDR levels, with the exception of saturated fat, which—at 11% of total calories—is just slightly more than the recommended limit of 10% of calories. (If you are interested in just exactly how well Americans have complied with the dietary recommendations of the past 30 years, you can find the gory details here.)  Far from being careless and casual consumers of anything and everything, Americans have radically shifted their eating patterns to match recommendations.

So why don’t Americans get any credit for actually lowering their fat intake and raising their carbohydrate intake, as we were told to do? I think there are a couple of things behind that.

First, I think one of the purposes of information like that presented in Figure 1 is to make sure the responsibility for overweight and obesity continues to rest squarely on the chubby little shoulders of Americans themselves and in no way reflects a possible lack of appropriateness of (or—gasp!—good scientific basis for) the Guidelines themselves. This is an attitude that pervades the Dietary Guidelines.

Second, the USDA’s Center for Nutrition Policy and Promotion would really like another $9 million to “help Americans develop eating behaviors that are more consistent with the Dietary Guidelines for Americans.” It would be a little awkward to ask for a funding increase to convince Americans to follow current dietary recommendations if we were already doing that—and they still weren’t working.

This is where recommendations become fanaticism.  According to Neil Postman, “the key to all fanatical beliefs is that they are self-confirming.”  The USDA and HHS seem unwilling to even acknowledge that the dietary shift that has occurred during the past thirty years has actually been in the direction of compliance with recommendations; in fact–according to Figure 1–they are willing to fudge the numbers to prove otherwise.  That’s not nice, and it’s sure not science.

References:

Welsh JA, Sharma A, Abramson JL, Vaccarino V, Gillespie C, Vos MB. Caloric sweetener consumption and dyslipidemia among US adults. JAMA. 2010 Apr 21;303(15):1490-7