Search results: app

The British journal, Public Health Nutrition, published a debate about ultra-processed foods this month.

Invited commentaries

CON:  Michael Gibney.  Ultra-processed foods in public health nutrition: the unanswered questions,

Several definitions of the degree of processing have been proposed. However, when each of these is used on a common database of nutritional, clinical and anthropometric variables, the observed effect of high intakes of highly processed food, varies considerably.. Moreover, assigning a given food by nutritional experts, to its appropriate level of processing, has been shown to be variable. Thus, the subjective definitions of the degree of food processing and the coding of foods according to these classifications is prone to error…Another issue that need[s] resolution is the relative importance of the degree of food processing and the formulation of a processed food. Although correlational studies linking processed food and obesity abound, there is a need for more investigative studies.

PRO: Mark Lawrence.  Ultra-processed foods: a fit-for-purpose concept for nutrition policy activities to tackle unhealthy and unsustainable diets.  Also an addendum: Ultra-processed foods: a fit-for-purpose concept for nutrition policy activities to tackle unhealthy and unsustainable diets.

This commentary describes the UPF concept as being fit-for-purpose in providing guidance to inform policy activities to tackle unhealthy and unsustainable diets. There is now a substantial body of evidence linking UPF exposure with adverse population and planetary health outcomes. The UPF concept is increasingly being used in the development of food-based dietary guidelines and nutrition policy actions. It challenges many conventional nutrition research and policy activities as well as the political economy of the industrial food system. Inevitably, there are politicised debates associated with UPF and it is apparent a disproportionate number of articles claiming the concept is controversial originate from a small number of researchers with declared associations with UPF manufacturers.

Letters to the editor

CON: Mark J Messina, John L Sievenpiper, Patricia Williamson, Jessica Kiel, John W Erdman.  Ultra-processed foods: a concept in need of revision to avoid targeting healthful and sustainable plant-based foods

we take issue with his perspective on our recently published article in which we make two fundamental points. First, the common criticisms of ultra-processed foods (UPF) do not apply to soya-based meat and dairy alternatives more so than they do to their animal-based counterparts, meat and cows’ milk, despite the former being classified as UPF and the latter as unprocessed/minimally processed foods. Second, NOVA is overly simplistic and does not adequately evaluate the nutritional attributes of meat and dairy alternatives based on soya….We therefore stand by our opinion that NOVA does a disservice to the public by suggesting that because soya burgers and soyamilk are NOVA-classified as UPF, they should be avoided. These foods can aid in the transition to and maintenance of plant-based diets.

PRO:  Mark Lawrence. The need for particular scrutiny of claims made by researchers associated with ultra-processed food manufacturers.

In this Commentary, I referred to challenges the UPF concept presents to researchers with declared associations with UPF manufacturers. The interplay between nutrition research and commercial interests is a widely recognised phenomenon in the commercial determinants of health literature…UPF-related research has become highly politicised and the integrity of the claims presented by researchers associated with UPF manufacturers demands close scrutiny.

Comment

In his letter, Mark Lawrence noted my having included the paper by Messina et al as one of my “industry-funded studies of the week” on this website.  In it, I reproduced the unusually long conflict of interest declaration of the authors, many of them disclosing ties to companies making ultra-processed foods.  Again, the ultra-processed concept is backed up by an extraordinary amount of research far beyond the point where it can be ignored or dismissed out of hand.

Professor Lawrence explains why there is so much pushback: “It [the UPF concept] challenges many conventional nutrition research and policy activities as well as the political economy of the industrial food system.”

Last week, I posted information and links to documents sent to me anonymously suggesting that the new Nordic Nutrition Recommendations (NNR) had been influenced by the food industry to omit a statement in an earlier draft to reduce consumption of ultra-processed foods.

I have no first hand personal experience with these recommendations and do not want to get in the middle of a dispute over the development of these guidelines.

I do feel strongly that the concept of ultra-processed is an enormous step forward in understanding how to eat more healthfully, backed up as it is by hundreds of observational studies and one extraordinarily well controlled clinical trial (Kevin Hall’s at NIH).  I think enough evidence exists, and the concept is well enough defined, to advise the public to eat less of highly processed food products.

Shortly after my post went online, I received the following letter from Norwegian researchers involved in the NNR process asking me to correct and clarify what I had posted.  I reproduce the letter here with their permission, and with thanks for our correspondence over this issue.  Read what they say and last week’s post, and decide for yourself.

July 12^th 2023

Dear Marion Nestle,

This email is from the Norwegian researchers involved with the recently published Nordic Nutrition Recommendations (NNR2023), including the head of the working group.

We have read your books, followed your daily blogposts for years, and always appreciated your informative and thoughtful letters. However, your post Monday 10th July on NNR2023 and the chapter on ultra-processed foods (UPF) is misinformed, and we believe that your informant has misled you. We would appreciate the opportunity to answer the claims, one by one.

• You: “The backstory here is one of effective food industry lobbying”.
  • This is 100 % untrue. The committee has not been subject to any form of lobbying unless one considers responses to the public hearing as lobbying. In the public hearing, which you have a link to, you cite that we received 60 responses (or to be correct: 58 responses when subtracting the heading and an empty entry) to the UPF chapter, but as the same institution could have several entries, there were 39 unique responses. Of these, 27 represented industry or commercial interests in one way or the other, while 12 responses were from academia.
  • If you read the responses carefully, you will see that absolutely ALL the academic institutions argue that it is premature to give public advice on UPFs. The academic responses came from the following institutions: Lund University, Nofima (a food research institute), Natural Resources Institute of Finland, Norwegian University of Technology and Science (NTNU), Technical Research Centre of Finland, SINTEF Ocean (Norway), RISE Research Institute of Sweden, Norwegian University of Life Sciences, Chalmers Technical College, Sweden’s Agricultural University (SLU), Karolinska, University of Helsinki, University of Lund, Swedish Food Agency, University of Gothenburg, and University of Umeå. (There are more than 12 institutions because several of them merged their responses into one entry).
  • You do not mention that there were three independent peer-reviewers of the UPF review paper, none of which has ties to the food industry
  • It is first and foremost careful listening to the input from the peer-reviewers and the scientific inputs from the public consultation, combined with our own evaluation of the totality of the evidence, that made us land on not having a specific recommendation on UPFs.
    • The arguments against having a recommendation on UPF are nicely summed up in this input to the public hearing (jointly signed by a number of scientists from Sweden): “In summary, the chapter introduces an unspecific concept that is controversial without a detailed discussion about its benefits and limitations. It is questionable whether the concept UPF adds anything beyond existing measures of diet quality since it is merely a proxy that includes both diet (nutrient) quality aspects, additives and processes. It is of outermost importance that NNR is based on solid scientific data and avoids speculations based on model studies and poorly defined exposures to maintain trust and credibility among the public and the research community. As researchers, we consider UPFs as an unspecific and non-scientifically defined concept that will make it difficult to study mechanisms and unravel causality. Instead, we suggest using existing and more well-defined and studied measures of diet quality and make efforts to come up with better ways of measuring food processing per see to allow a scientific evaluation of its potential implications for human health. This could be reflected in a narrative chapter that introduces and discuss the concept of UPF and food processing and their benefits and limitations in a balanced way as well as identifies scientific gaps in our understanding of the role of different processing and additives for health”.
    • As an example, whole-grain bread does not become unhealthy just because it is placed in the UPF group.
• You: “These negative views of the UPF concept differ from the views of the background document (however politely stated) and clearly were influenced by the overwhelmingly negative views of food industry representatives”.
  • Yes, the food industry representatives were negative, but as explained in the previous comment, so were absolutely ALL the Nordic scientists who responded in the public hearing. The result would have been the same regardless of the comments from industry.
• You refer to a summary in English available on online: https://docs.google.com/document/d/10Kf4kuaD1wZNkQJyrdOHdQPvsDqY6O6pytizzBxfpRA/edit?lctg=102461686&pli=1 This is an anonymous summary, but likely written by the same person who is your informant
• You cite your informant who states the following: “I have come to realize that this is not at all about evidence. It’s about power, and who gets to define what’s important in nutrition science. “The establishment” refuses to accept that someone from Brazil, a country they regard as inferior, should be allowed to tell them they have been wrong in their nutritionism-approach. They claim NOVA is based on ideology, not science….And now this is getting in the way of public health”.

This is an outrageous claim and we wonder how anyone can accuse us of something like this. We have the deepest respect for Carlos Monteiro and have followed his research on UPF since he first published his hypothesis in 2009. Like him, we are deeply concerned about the rise of overweight and obesity worldwide and like him, we work on disentangling the causes. We find the UPF concept intriguing scientifically, but it’s premature to use the concept in public advice until it has been refined and better defined.

We are also surprised that you do not mention the large proportion of comments coming from the meat industry and farmer’s organizations regarding both health and sustainability aspects of meat consumption. They have of course been fervently opposed the science advice to reduce meat consumption to maximum 350 grams red meat/week, generating significant media attention and engaging with politicians to dismiss the report. This would itself certainly be an interesting case study. However, the committee again adhered to the science and did not succumb to lobbyism. The same goes for sugars, alcohol and other hot topics. This is contrary to the accusations that the recommendations were influenced by the food industry.

We regret to note that you have shared a letter containing misleading allegations regarding the NNR2023 results on UPFs. The unfounded accusations of NNR2023 seem to come mainly from persons who are also in opposition to the NNR2023 advice on reducing red meat intake, thus being in opposition to a more environmentally sustainable diet. Nonetheless, we do hope that you will look more closely into the final NNR2023 report (not the draft) and modify the damaging and untruthful assertions about the process.

Yours sincerely

Helle Margrete Meltzer, member of the NNR2023 committee, former research director at the Norwegian Institute of Public Health

Rune Blomhoff, head of the NNR2023 committee, professor at the University of Oslo

Jacob Juel Christensen, member of the NNR2023 committee, postdoc at the University of Oslo

Erik Kristoffer Arnesen, advisor to the NNR2023 committee, PhD student at the University of Oslo

The long-awaited report on aspartame from the International Agency for Research on Cancer and the WHO and FAO Joint Expert Committee on Food Additives (JECFA) are now out.  These agencies jointly issued two documents.

A press release

Citing “limited evidence” for carcinogenicity in humans, IARC classified aspartame as possibly carcinogenic to humans (IARC Group 2B) and JECFA reaffirmed the acceptable daily intake of 40 mg/kg body weight.

A summary of the findings

• The [IARC] working group classified aspartame as possibly carcinogenic to humans (Group 2B) based on limited evidence for cancer in humans (for hepatocellular carcinoma, a type of liver cancer)…There was also limited evidence for cancer in experimental animals…In addition, there was limited mechanistic evidence that aspartame exhibits key characteristics of carcinogens, based on consistent and coherent evidence that aspartame induces oxidative stress in experimental systems and suggestive evidence that aspartame induces chronic inflammation and alters cell proliferation, cell death and nutrient supply in experimental systems.
• The [JEFCA] Committee concluded that the data evaluated during the meeting indicated no reason to change the previously established acceptable daily intake (ADI) of 0–40 mg/kg body weight for aspartame. The Committee therefore reaffirmed the ADI of 0–40 mg/kg body weight for aspartame…Based on the results of the oral carcinogenicity studies of aspartame, the absence of evidence of genotoxicity, and a lack of evidence on a mechanism by which oral exposure to aspartame could induce cancer, the Committee concluded that it is not possible to establish a link between aspartame exposure in animals and the appearance of cancer.

If this feels crazy-making, I’m with you.

For starters, I’ve never seen a scientific report released this way—essentially by leakage and press release before the research is published where it can be reviewed independently.

To summarize the chronology:

• June 29: Reuters releases leaked information that aspartame is soon to be declared a carcinogen (I wrote about this in a post on July 6)
• June 29: American Beverage Association releases statement: “There is a broad consensus in the scientific and regulatory community that aspartame is safe.”
• July 1: Vox publishes a an article with the provocative title, “The WHO is about to declare aspartame can cause cancer. Here’s why you should listen.”
• July 12: Reporters tell me that they participated in a press conference with WHO and IARC to discuss what the reports will say when they are released at 12:30 a.m. ET on July 14.
• July 12: Anahad O’Connor writes in the Washington Post: “Does aspartame pose a health risk? Here’s what the science says” (I’m quoted in it).
• July 12 and 13: The agencies send reporters copies of press releases on embargo (see above), but not the published data.
• July 13: Reporters get copies of a statement from the FDA disagreeing with IARC.
• July 14:  Everything comes off embargo, including these four pieces:

1. Research article in Lancet Oncology:  Carcinogenicity of aspartame, isoeugenol, and methyleugenol 
2. Infographic
3. Q & A
4. Featured News page on the evaluation of aspartame

Here’s what I think of all this: if aspartame is a carcinogen, it’s a weak one.

But it is artificial and off my dietary radar.  It’s not essential in human diets.  I don’t like its taste and I don’t like all the iffy questions about how it is metabolized.  I avoid it.

You don’t want to avoid it?  JEFCA says you can have 9 to 14 cans of diet soda a day without exceeding tolerable limits.  If you want one once in a while, it is highly unlikely to hurt you.

But a much better idea is getting out of the sweetened-drinks habit.  If you must have something sweet to drink, try adding fruit juice to water.

A reader who wishes to remain anonymous sent me an account of the development of the new Nordic Nutrition Recommendations, pointing out what they do not contain: a recommendation to reduce ultra-processed foods [Note: this is an updated and slightly corrected version of what was first posted on July 9].

Indeed, on pages 253-255 (this is a long report), you will find this statement:

The backstory here is one of effective food industry lobbying.

The Nordic Nutrition Recommendations do not say:  reduce consumption of ultra-processed foods.

The story begins with two authors who were asked to sum up the health effects of ultra-processed foods, and to advise the committee writing the recommendations.  They did so.  Their initial background paper concluded with these recommendations:

(1) Limit the consumption of ultra-processed foods.

(2) Choose less processed form of foods within each food group when possible.

(3) Cook at home and choose freshly prepared foods when eating out.

The committee revised the background paper.  It omitted the three recommendations but concluded:

Recommendations to limit ultra-processed foods, and choose foods of lower processing level, when possible, may enhance and support several of the existing FBDGs [food-based dietary guidelines] and help individuals select more healthful foods that align with the overall NNR2022 [last years Nordic Nutrition Recommendations] guidelines within each food category. For example, such advice would support choosing plain, unsweetened yoghurt instead of flavored, sweet yoghurt; choosing oatmeal or muesli based on grains, nuts, and dried fruits over sweetened, refined breakfast cereals; and choosing chicken breast/thighs over chicken nuggets.

The revised document was opened for public comment and a hearing.  A great many representatives of food companies objected to saying anything negative about ultra-processed foods.  This Excel spreadsheet lists the 60 people who commented and their main objections.

After the hearing, the committee preparing the recommendations wrote a draft report based on the comments.  The section on ultra-processed foods is on pages 152-153.  It begins:

There is currently no consensus on classification of processing of foods, including UPFs. The dominating UPF classification (NOVA classification group 4) contains a variety of unhealthy foods, but also a number of foods with beneficial health effects.

It also says:

Health effects. Regular intake of UPF encourages over-eating and intake of foods in the UPF category of the NOVA classification has been suggested associated with increased risk of obesity, cardiovascular disease, type 2 diabetes, cancer, depression, and premature mortality …However, no qSRs [qualified systematic reviews] support these suggestions.

These negative views of the UPF concept differ from the views of the background document (however politely stated) and clearly were influenced by the overwhelmingly negative views of food industry representatives.

The draft report also was opened for public comment.  These comments also are listed in an Excel document. Some favor the changes benefiting the food industry; others—but many fewer—object to them (these last are summarized in yet another document).

The final Nordic Nutrition Recommendations are somewhat of a compromise between public health and food industry views, but generally favor the food industry position.  The new Nordic Nutrition Recommendations are less critical of the UPF concept, but do not say “reduce consumption of ultra-processed foods.”

The NOVA food classification system, which first defined ultra-processed foods, was published by Carlos Monteiro, a professor of public health at the University of São Paulo, and his colleagues in 2009.*  About the Nordic recommendations, my informant writes:

I have come to realize that this is not at all about evidence. It’s about power, and who gets to define what’s important in nutrition science. “The establishment” refuses to accept that someone from Brazil, a country they regard as inferior, should be allowed to tell them they have been wrong in their nutritionism-approach. They claim NOVA is based on ideology, not science….And now this is getting in the way of public health.

My take-home lesson:  The food industry came out in force on this issue and greatly overwhelmed the few comments of public health advocates.  The message here seems clear: public support for reduction of ultra-processed food needs to be widespread, clear, and forceful.

*Definition of ultra-processed foods

• Industrially produced
• Bearing no evident relationship to the foods from which they were derived
• Formulated to be irresistably delicious (if not addictive)
• Usually containing color, flavor, and texture additives
• Often high in salt, sugar, and fat (but these are culinary ingredients that do not in themselves make foods ultra-processed)
• Cannot be made in home kitchens (because they are industrially produced and contain ingredients unavailable to home cooks)

Addition

An additional document was sent to me after this post and the response from nutritionists involved in the NNR, which I posted the following week.  It is from the authors of the background document expressing their concerns about the changes made.

I was deluged with interview requests last week over the rumor that the World Health Organization will soon release reports stating that the artificial sweetener aspartame is “possibly” carcinogenic.

I say rumor, because the reports will not be released until July 14.

According to Reuters—Exclusive: WHO’s cancer research agency to say aspartame sweetener a possible carcinogen -sources—two sources leaked the conclusion.

Aspartame, used in products from Coca-Cola diet sodas to Mars’ Extra chewing gum and some Snapple drinks, will be listed in July as “possibly carcinogenic to humans” for the first time by the International Agency for Research on Cancer (IARC), the World Health Organization’s (WHO) cancer research arm, the sources told Reuters…. Last month, the WHO published guidelines advising consumers not to use non-sugar sweeteners for weight control. The guidelines caused a furore in the food industry, which argues they can be helpful for consumers wanting to reduce the amount of sugar in their diet.

From what I hear from my own sources, everyone involved in the forthcoming reports is bound by confidentiality agreements.  They suspect that food industry representatives did the leaking.

This gives the industry plenty of time to complain and lobby.  As one report has it, “Industry experts and trade groups are decrying the World Health Organization’s International Agency for Research on Cancer’s pending addition of aspartame to a list of possible carcinogens for humans as unscientific and politically motivated.”

Aspartame has been under scrutiny for its potential harm to health practically from the time it first appeared. (see Laura Reiley in the Washington Post on how aspartame has come under scrutiny lately).

Center for Science in the Public Interest has long said of aspartame, Avoid.

Aspartame (sometimes marketed under the brand names Equal, NutraSweet, or AminoSweet) is a chemical combination of two amino acids and methanol. Questions of cancer and neurological problems, such as dizziness or hallucinations, have swirled around aspartame for decades…In 2005, researchers at the Ramazzini Foundation in Bologna, Italy…found that rats exposed to aspartame starting at eight weeks of age and continuing through their entire lifetimes developed lymphomas, leukemias, and other tumors, including kidney tumors, which are extremely rare in the strain of rat used. In 2007, the same researchers published a follow-up study that exposed rats to aspartame beginning in the womb and continuing through their entire lifetimes. That study, too, found that aspartame caused leukemias/lymphomas, as well as mammary (breast) cancer. Then in 2010, they published a study that exposed mice to aspartame, starting in the womb and continuing throughout their entire lifetimes. That third study found that aspartame caused liver and lung cancer in male mice.

US Right to Know says of Aspartame, “Decades of Science Point to Serious Health Risks.”

But the FDA says “aspartame is safe for the general population when made under good manufacturing practices and used under the approved conditions of use.”

And the American Cancer Society says you would have to drink 36 cans of diet soda a day to excede the Acceptable Daily Intake level.

Rumors and concerns about aspartame causing a number of health problems, including cancer, have been around for many years. Some of the concerns about cancer stem from the results of studies in rats published by a group of Italian researchers, which suggested aspartame might increase the risk of some blood-related cancers (leukemias and lymphomas). However, later reviews of the data from these studies have called these results into question. The results of epidemiologic studies (studies of groups of people) of possible links between aspartame and cancer (including blood-related cancers) have not been consistent.

A recent review says “The consumption of ASBs [artifically sweetened beverages] was associated with a higher risk of obesity, type 2 diabetes, all-cause mortality, hypertension, and cardiovascular disease incidence.”

As I mentioned a month or so ago, artificial sweeteners are taking a big hit these days and it looks like they are about to take another one.

In my intereviews, I pointed out that what’s news here is the level of authority.  It’s a big deal that WHO is saying this.

Two other points.

• Aspartame is not essential in the diet.  Nobody (except soft drink companies) need it.
• It and other artificial sweeteners are artificial and, therefore, ultra-processed.
• I’m already seeing “no aspartame” labels on soft drinks and food products.

I am looking forward to seeing the data when the reports are published.

The FDA is asking for public feedback on an updated research study to decide which front-of-package labeling design will work best to help the public choose healthy fpackaged foods.

To submit comments, go here.  They are due by July 17.

I’ve written about this issue previously.

The FDA tried to do this a decade ago.  But the Grocery Manufacturers Association (now Consumer Brands Association) did an end run and volunteered to use Facts Up Front/Guideline Daily Amounts, which nobody understands or pays attention to.  The FDA caved in and let that happen.

Now countries all over the world are putting warning labels on foods high in calories, fat, salt, and sugar, most of them ultra-processed.

The FDA says it will  test 8 front-of-package label designs to see which work best in conveying healthfulness. The study materials are here and here.

Earlier, if those links don’t work, it proposed to test all of these designs.

I don’t think any of the choices is as compelling as Chile’s warning labels, which can be understood easily by children and people who cannot read.

Among the FDA’s choices, here’s my preference (it’s most like the labels from Canada and Brazil).

This still requires people to figure out what it means if the colors differ, as they do here, but surely everyone will understand that the more red boxes, the worse.

One other complaint: Since this effort started, the concept of ultra-processed has become much more prominent and is backed up by a tremendous amount of research.

Avoiding ultra-processed foods is the key message needed now.

The FDA’s proposals will take care of most ultra-processed foods, but miss the point.  Whatever the FDA chooses will be out of date no matter when it appears.

Never mind.  This is a step in the right direction.  Food industry opposition to any of it is strong.

It’s important to tell the FDA to get busy on this, and to strengthen the warning.

Write the FDA NOW!

Earlier this week I wrote about the UNICEF-WHO meeting I went to in Geneva on implementing the 1981 International Code governing marketing of infant formulas.

UNICEF has just issued an update: What I [meaning you] Should Know about the Code

This new publication—a one-stop shopping guide to the issues—summarizes UN resolutions on the Code since 1981 as well as subsequent research on breastfeeding and infant formula marketing, most notably the Lancet Commission reports I wrote about earlier.

Incontrovertible evidence demonstrates how inappropriate marketing of infant formulas undermines breastfeeding and can harm children, especially in places that do not have clean water to dilute formulas.

Every country in the world has committed to the Code—the United States was the last holdout.  We do not seem to pay much attention to the Code’s provisions.

Here is one example.  The Code says:I’m not sure how to interpret the “except” phrase, except that our FDA must think that the health claims on a product like this are entirely acceptable, whereas they would not be allowed in many other countries.  [Reference 23 refers to UN General Assembly Resolution 63.23.]

The Code states that infant formulas should not be labeled in any way that suggests formula might be superior to breast milk.  This and the accompanying statement on the product website, would appear to violate that guideline.

Infant formulas do a good job of substituting for the nutrients in breast milk.  Because the FDA tightly regulates their ingredients, they are all pretty much alike, although they vary in price enormously.

The infant formula industry deserves close scrutiny of its marketing practices and this UNICEF publication is an excellent place to begin.

I have been asked to comment on the American Medical Association’s resolution to stop using the BMI as the sole criterion for diagnosing obesity [To find this resolution, click on CCSPH Report(s) #07: Support Removal of BMI as a Standard Measure in Medicine and Recognizing Culturally-Diverse and Varied Presentations of Eating Disorders].

The BMI—Body Mass Index—defined as weight in kilograms divided by height in meters squared—is a quick way to categorize the relationship of weight to height and does a better job of identifying people with excessive body fat than most other simple and inexpensive measures.

Unfortunately, not everyone demonstrates a close correlation of BMI to body fat and those who don’t may well find themselves discriminated against in the health care system.

The BMI is also an imperfect measure of health risk:

The current BMI classification system is also misleading regarding the effects of body fat mass on mortality rates. Numerous comorbidities, lifestyle issues, gender, ethnicities, medically significant familial-determined mortality effectors, duration of time one spends in certain BMI categories, and the expected accumulation of fat with aging are likely to significantly affect interpretation of BMI data, particularly in regard to morbidity and mortality rates…[This report] outlines the harms and benefits to using BMI and points out that BMI is inaccurate in measuring body fat in multiple groups because it does not account for the heterogeneity across race/ethnic groups, sexes, and age-span.

The resolution recommends:

(1) greater emphasis in physician educational programs on the risk differences among ethnic and age within and between demographic groups at varying
levels of adiposity, BMI, body composition, and waist circumference and the importance  of monitoring these waist circumference in all individuals with BMIs below 35 kg/m2;

(2) additional research on the efficacy of screening for overweight and obesity, using different indicators, in improving various clinical outcomes across populations, including morbidity, mortality, mental health, and prevention of further weight gain; and

(3) more research on the efficacy of screening and interventions by physicians to promote healthy lifestyle behaviors, including healthy diets and regular physical activity, in all of their patients to improve health and minimize disease risks.

My translation: Keep using the BMI as an indicator, but also pay attention to body composition and waist circumference as better measures of body fat.

The AMA is not minimizing the importance of excess body fat as a disease risk factor.  It is saying that only using the BMI to evaluate the risk itself risks stigmatizing patients, especially those of non-majority race, ethnicity, and gender conformation.

This resolution ought to further sensitize physicians to such issues.  If it does, it could not come a better time.

Resources

• Stat News on the resolution
• Ancel Keys et al’s original paper on the BMI: Indices of relative weight and obesity.

I am putting the Keys’ paper into this discussion to demonstrate that Keys was quite well aware of the strengths and weaknesses of the BMI, which was intended mainly to identify groups and populations at risk of undernutrition.

Guided by the criteria of correlation with height (lowest is best) and to measures of body fatness (highest is best), the ponderal index is the poorest of the relative weight indices studied.  The ratio of weight to height squared, here termed the body mass index, is slightly better in these respects than the simple ratio of weight to height. The body mass index seems preferable over other indices of relative weight on these grounds as well as on the simplicity of the calculation and, in contrast to percentage of average weight, the applicability to all populations at all times.