by Marion Nestle

Currently browsing posts about: IOM (Institute of Medicine)

Oct 22 2010

The latest salvos in the sodium debates

Scientific debates about the role of sodium in high blood pressure go on and on.  Committees of scientists reviewing the research invariably conclude that people would be healthier if they ate less salt (salt is sodium chloride).  The 2010 Dietary Guidelines Advisory Committee is only the most recent group to urge population-wide reductions in sodium intake.

The Institute of Medicine has just issued a new report on reducing sodium.  Its Report in Brief gives a quick summary

As its primary strategy for sodium reduction, the committee recommends that the FDA set mandatory national standards for the sodium content in foods…beginning the process of reducing excess sodium in processed foods and menu items to a safer level. It is important that the reduction in sodium content of foods be carried out gradually…Evidence shows that a decrease in sodium can be accomplished successfully without affecting consumer enjoyment of food products if it is done in a stepwise process that systematically and gradually lowers sodium levels across the food supply.

But wait!  Hypertension rates have been increasing for years without any change in sodium excretion, says a report in FoodNavigator.com.  The report refers to new study in this month’s American Journal of Clinical Nutrition reviewing trends in sodium excretion from 1957 to 2003.

Sodium excretion, a precise reflection of intake, say Adam Bernstein and Walter Willett of the Harvard School of Public Health, has not changed in the last half century, despite rising rates of high blood pressure.   Instead, they suggest that rising rates of obesity might be the cause.

The accompanying editorial, by David McCarron and his colleagues, takes the argument even further as can be seen just from its title: “Science trumps politics: urinary sodium data challenge US dietary sodium guideline.

The editorial says that this new study provides:

plausible, scientific evidence of a “normal” range of dietary sodium intake in humans that is consistent with our understanding of the established physiology of sodium regulation in humans. This scientific evidence, not political expediency, should be the foundation of future government policies….Guidance for sodium intake should target specific populations for whom a lower sodium intake is possibly beneficial. Such an approach would avoid broad proscriptive guidelines for the general population for whom the safety and efficacy are not yet defined.

Is this review likely to change the Dietary Guidelines due out later this year?  The Advisory Committee was convinced that the preponderance of evidence favors the importance of sodium as a causative agent in high blood pressure.

Because so much is at stake for the processed food industry, this argument is not likely to be resolved quickly.  Stay tuned.

Oct 13 2010

IOM Front-of-Package Label Committee releases Phase 1 report

The Institute of Medicine (IOM) released its first Front-of-Package (FOP) labeling report this morning. Phase I is a tough, detailed examination of about 20 of the existing FOP schemes along with some recommendations about what such schemes ought to do.

FOP labels are those little spots, check marks, and tokens that are all over food packages these days and that are supposed to indicate that the product is especially healthy for you.  They may seem utterly trivial, but they are of desperate importance to food companies.  FOP labels sell food products.  Food marketers love them and need them.  The FDA worries that having so many of them confuses the public, and that the schemes are based on criteria that serve industry purposes more than to promote public health.

As the IOM press release explains:

A multitude of nutrition rating, or guidance, systems have been developed by food manufacturers, government agencies, nutrition groups, and others in recent years with the intent of helping consumers quickly compare products’ nutritional attributes and make healthier choices. Ratings are typically communicated to shoppers through symbols placed prominently on food packaging, usually on the front, or on retail shelf tags. Unlike the Nutrition Facts panel, these rating systems and symbols are unregulated, and different systems focus on different nutrients. The variation may confuse consumers, and questions have been raised about the systems’ underlying nutritional criteria.

The committee did a terrific analysis of current FOP schemes.  My favorite parts are its

  • Clear, concise histories of nutrition and FOP labeling (students: take note!)
  • Detailed evaluation of the strengths (few) and weaknesses (many) of the existing schemes
  • Demonstration of the inconsistent results of applying the schemes to specific foods

The report gives examples of the inconsistent results of three scoring schemes: Guiding Stars, NRFI [Nutrient-Rich Foods Index], and Nu-Val

  • Instant oatmeal received 3 Guiding Stars, and scores of 87 by NRFI and 39 by NuVal.
  • Non-instant oatmeal received 2 Guiding Stars, and scores of 22 by NRFI and 57 by NuVal
  • Toasted oat cereal received 2 Guiding Stars, and scores of 84 by NRFI and 37 by NuVal
  • Fat free milk, 1% fat milk, and fat free plain yogurt received 3 Guiding Stars, but fat free milk was scored 56 by NRFI and 91 by NuVal; 1% fat milk was scored 30 by NRFI and 81 by NuVal, and fat free plain yogurt was scored 43 by NRFI and 96 by NuVal.

The committee’ key recommendation: FOP labels should deal with just four nutrients: calories, saturated fat, trans fat, and sodium.

These nutrients, says the committee, “are routinely overconsumed and associated most strongly with diet-related health problems affecting many Americans, including obesity, heart disease, high blood pressure, Type 2 diabetes, and certain types of cancer.”

Comment: Trans fat seems unnecessary here.  It is already out of most packaged foods.   Or maybe the committee thinks that leaving it off will give food companies permission to put hydrogenated oils back in?

The committee chose not to add sugars to this list:

The committee concurred that both added and naturally occurring sugars contribute to the caloric content of foods and beverages and overconsumption of high-calorie products can lead to obesity.  Highlighting calories per serving in nutrition rating systems would address this concern.

Comment: I think consumers want to know about added sugars in food products.  I certainly do.

Phase II comes next

It will examine designs and look at consumer understanding of the labels, and will discuss “the pros and cons of having a single, standardized front-label food guidance system that is regulated by the Food and Drug Administration.”

Presumably, Phase II will deal with questions that are not addressed in the Phase I report:

  • Will this scheme supersede all of the other labeling systems currently on food packages?
  • Will it be voluntary or mandatory?  For all food products, or just selected ones?
  • If the scheme is voluntary, why would food companies choose to use it since it mostly highlights the negatives—the nutrients to be avoided?
  • How will it affect the nutrient-content claims currently on food packages?  (Examples: “Contains 8 vitamins!”  “100% vitamin C!” “High fiber!”)
  • How will it affect shelf-labeling schemes such as the Nu-Val system used at Price Chopper supermarkets and the ANDI system used by Whole Foods?

FOP labels are about marketing, not health

This scheme, like the many others developed by food companies singly or together, is designed to help the public decide whether one highly processed, packaged food product is nutritionally better than another.

As I have discussed many times on this site, this approach raises a philosophical question: Is a slightly “better for you” food product necessarily a good choice?

I hope the committee will ponder this and some of my other questions as it enters Phase II.

Addendum: I gather from what I’ve heard about the press conference this morning that some of my questions were answered.  The FOP proposal will not affect nutrient content claims on the front of packages.  Companies will still be able to proclaim the nutritional benefits of their products in words and banners.  They just won’t be able to use them in whatever symbol gets chosen.  So what difference will this report make?  Not much, alas, except to get rid of the silly symbols in use right now.

Update, October 14:  William Neuman’s account of this event in the New York Times starts with this: “Tell us how your products are bad for us.”

May 12 2010

IOM wants just as rigorous science for food claims as for drugs

Buried in an Institute of Medicine report released today on, of all things, “biomarkers and surrogate endpoints in chronic disease” are some truly astonishing recommendations:

Rec. 3: The FDA should use the same degree of scientific rigor for evaluation of biomarkers across regulatory areas, whether they’re proposed for use in the arenas of drugs, medical devices, biologics, or foods and dietary supplements.

Rec. 4: The FDA should take into account a nutrient’s or food’s source as well as any modifying effects of the food or supplement that serves as the delivery vehicle and the dietary patterns associated with consumption of the nutrient or food when reviewing health-related label claims and the safety of food and supplements.

Translation: The FDA should require the same level of scientific substantiation for health claims as for pharmaceutical drugs, and not assume that a supplement has the same health effect as a food or diet.

As the press release states:

The FDA should apply the same rigor to evaluating the science behind claims of foods’ and nutritional supplements’ health benefits as it devotes to assessing medication and medical technology approvals…There are no scientific grounds for using different standards of evidence when evaluating the health benefits of food ingredients and drugs given that both can have significant impacts on people’s well-being.

The committee set out to recommend scientific criteria for evaluating the types of scientific data that companies use to convince the FDA to allow health and safety claims.  Food claims got tossed into the mix. 

The impact of these recommendations could be considerable.  The IOM is saying that health claims need to have rigorous science to back them up, not least because the kinds of claims now used to market foods do not come close to meeting those criteria.

Here’s what the Wall Street Journal has to say about this report (it quotes me).

How right they are, as witnessed by the health claims on chocolate-flavored, sugar-sweetened Enfagrow.

Apr 10 2009

Consumers prefer traffic-light food labels

Lots of well meaning people are trying to develop systems for labeling foods by their degree of nutritional quality (I file posts on this topic under Scoring systems).  My preference is for traffic lights — green for eat anytime, yellow for once-in-a-while, and red for hardly ever).  So I was not surprised to see an announcement of a new study from Australia that tested consumers’ understanding of several kinds of food ranking systems.  According to the study itself, traffic lights beat out the other systems tested in helping consumers choose healthier foods.  I hear rumors that the Institute of Medicine is starting a study to evaluate consumers’ understanding of the various kinds of ranking labels on food products.  I suppose we will need to wait until that study is complete – a process that usually takes two or three years – before we hear its conclusion.  If we have to have one system, I’m voting for traffic lights.