by Marion Nestle

Currently browsing posts about: Dietary-Guidelines

Jun 6 2024

Dietary guidelines III. They haven’t changed since the late 1950s

Despite all the fuss about the guidelines every five years, they say the same things every time: eat more fruits and vegetables (plant foods), balance calories (good luck with that), and reduce intake of saturated fat, sugars, and salt (euphemisms for ultra-processed foods).

You don’t believe me?  Take a look:

Ancel and Margaret Keys’ 1959 dietary guidelines for prevention of coronary heart disease.*

  1. Do not get fat, if you are fat, reduce.
  2. Restrict saturated fats, the fats in beef, pork, lamb, sausages, margarine, solid shortenings, fats in dairy products.
  3. Prefer vegetable oils to solid fats, but keep total fats under 30% of your diet calories.
  4. Favor fresh vegetables, fruits, and non-fat milk products.
  5. Avoid heavy use of salt and refined sugar.
  6. Good diets do not depend on drugs and fancy preparations.
  7. Get plenty of exercise and outdoor recreation.
  8. Be sensible about cigarettes, alcohol, excitement, business strain.
  9. See your doctor regularly, and do not worry.

*Keys A, Keys M.  Eat Well and Stay Well.  New York: Doubleday & Co, 1959.

The concept of ultra-processed foods encompasses much of this.  We would be better off eating less of them.

It shouldn’t take all this work every five years to come to this conclusion.

So why all the fuss?  I’d call it food politics.

If people ate healthfully, chronic disease prevalence would decline and lots of industries would be out of business: junk food, diet foods, diet drugs, and those profiting from health care.

Jun 4 2024

Dietary guidelines I. Ultra-processed foods

I don’t like writing about the dietary guidelines process while it is still ongoing because so much can change between now and the time the advisory committee submits its report, and USDA and HHS issue the actual guidelines.

But this Dietary Guidelines Advisory Committee is dealing with the concept of ultra-processed foods and is tied in knots over it.

So I will devote this week to the guidelines.

  • Today: Why knots?
  • Wednesday: Why isn’t NIH funding more rigorous nutrition research?
  • Thursday:  Why all the fuss when guidelines always say the same things?

OK.  Let’s get to it.

Why do I think the Dietary Guidelines Advisory Committee (DGAC) is tied in knots over ultra-processed foods (UPF)?

  1. It  is required to make evidence-based recommendations.  This is impossible with observational evidence.
  2. It is required to exclude the one existing controlled clinical trial from consideration (because it was too short).

Therefore, it had to conclude: ““Limited evidence suggests that dietary patterns with higher amounts of foods classified as UPF consumed by adults and older adults are associated with greater adiposity (fat mass, waist circumference, BMI) and risk of obesity/overweight. Evidence Grade: Limited.”

The DGAC is in an impossible position, and doing the best it can under the circumstances.

I need to say a word about evidence-based recommendations.  How I wish they could be.   If all you have is observational studies, you need to interpret them carefully.  Interpretation is subject to bias.

When I was a DGAC member (1995 guidelines), the agencies recognized what we were up against.  They instructed us to review the available research and give the best advice we possibly could based on it.

All of this raises a philosophical question: Should government agencies issue advice based on incomplete and inadequately controlled observational research?  Or should they say nothing?

This committee, apparently, is considering saying nothing about ultra-processed foods: “It would be hugely problematic to tell people to avoid 60% of the food supply without having something good to replace it.”

Really?  Plenty of “something good” is available.  It’s called food: fruits, vegetables, grains, meat, fish, dairy, eggs.

These—unprocessed and minimally processred—can be delicious, nutritious, and satisfying, and at reasonable cost.


Tomorrow: Why don’t we have more rigorous research?

Addition:  The video of the meeting.  The discussion of ultra-processed foods starts at 3:51:45 .

Feb 23 2024

Weekend reading: FAO calls for food systems-based dietary guidelines

The U.N.’s Food and Agriculture Organization (FAO) is taking the lead on bringing dietary guidelines into the 21st Century.

It is calling for national dietary guidelines not only to be nutrient-based and food-based, but food systems-based.

Food systems-based guidelines extend beyond food-based guidelines that “provide advice on foods, food groups and dietary patterns to provide the required nutrients to the general public to promote overall health and prevent chronic diseases.”

Food system-based guidelines not only address health and nutritional priorities but also consider sociocultural, economic, and environmental sustainability factors.  This means

context-specific multilevel recommendations that enable governments to outline what constitutes a healthy diet from sustainable food systems, align food-related policies and programmes and support the population to adopt healthier and more sustainable dietary patterns and practices that favour, among other outcomes, environmental sustainability and socio-economic equity.

This is a huge advance.  It means that sustainability issues are essential components of dietary advice.

From now on, dietary guidelines that do not consider sustainability are out of date.

Note: By order of Congress, the 2015-2020 Dietary Guidelines did not consider sustainability in its meat recommendations and sustainability was off the table for the 2020-2025 Dietary Guidelines and also for the 2025-2030 version now underway.  This means the new guidelines issues in 2025 will be dated and largely irrelevant to the modern era.

Unless the Advisory Committee gets to work.  I hope it does.

Dec 7 2023

No, Virginia, correlation does not necessarily signify causation

On Thursdays I like posting things I want everyone to enjoy.

This one, I stole from Tamar Haspel, who writes about food for the Washington Post.

I follow her on X (the site formerly known as Twitter), where she recently posted:

This could be my all-time favorite BMI correlation!

In China and post-Soviet states, BMI correlates with corruption. The fatter, the crookeder.

The correlation she cites is from an article in the Economist, Are Overweight Politicians Less Trustworthy?










I agree.  This is a fabulous example of how correlation does NOT mean causation—a basic tenet of epidemiology often forgotten.

But here’s my personal favorite example.  I laugh every time I see it.


No, the Dietary Guidelines did not cause the prevalence of obesity to rise.

This is correlation, NOT causation.

For causes, please consider food overproduction, pressures on food companies to sell food when there is so much of it, and the shareholder value movement, which demands not only profits, but  continual growth in profits.  All of these forced food companies to find new ways to get everyone to eat more food (by creating an “eat more” food environment.  I discuss all this in Food Politics and my other books).

Correlation is lots of fun but causation requires much deeper analyses.

Sorry about that.

Thanks Tamar.

Oct 17 2023

US Right to Know reports on conflicts of interest in members of the 2025 Dietary Guidelines Advisory Committee

I received an emailed press release from Gary Ruskin at US Right to Know: Report: Nearly Half of Dietary Guidelines Advisory Committee Have Conflicts of Interest.

Nine out of 20 members of the Dietary Guidelines Advisory Committee have conflicts of interest with food, pharmaceutical, or weight loss companies or industry groups with a stake in the outcome of the guidelines, according to a new report published today by the nonprofit public health research group U.S. Right to Know. An additional four members had possible conflicts of interest. The report found that Abbott, Novo Nordisk, National Dairy Council, Eli Lilly, and Weight Watchers (WW) International had ties to two or more DGAC members.

My immediate reaction: Only 9?  Last time, it was 19 out of 20.

Some background

The agencies responsible for the guidelines, HHS and USDA, issued aggregated disclosures of committee members relationships with industry. These treated real conflicts (Mars, Egg Nutrition Center, Novo Nordisk) with non-conflicts (National Science Foundation, Ohio Department of Medicaid) as if they were equivalent; they are not.

The sponsoring agencies have always argued that it is impossible to find nutrition experts without industry ties.  I disagree.  It’s just that people like me who are careful to avoid industry ties are considered too biased to serve on such committees (or so I’ve been told, repeatedly—I’ve not been asked to serve on a federal committee since Food Politics came out).

Do industry ties influence the report?  This is less of a problem than it used to be.  When I was on the DGAC in 1995, our committee set the research questions, did the research, wrote the research report, and wrote the actual Dietary Guidelines.  The agencies did light editing.

That changed in 2010 (administration of Bush II) when the agencies took over writing the guidelines.

In 2020, the agencies wrote the research questions, and they did so again this round.

This means that the only thing left for the DGAC to do is to review the research on questions determined by the agencies.

What is US Right to Know?

This group has initiated and “co-authored 15 peer-reviewed public health studies revealing how the food and beverage industries and industry-funded groups try to influence public opinion, scientific research, public health conferences and government policies related to diet and nutrition.”

A reader, Leah Murphy, wrote me questioning USRTK’s funding (see Appendix D in the report).

“Funding for the report was provided by Feed the Truth, a 501c3 non-profit that is funded by the Lubetzky Family Foundation.”

Daniel Lubetzky is the founder of KIND, a food company.  My point is that a food company funds the non-profit that funded the report. And that seems to undermine the credibility of their report and could qualify under their definition as a COI.

Ordinarily, I would agree that this could be a problem, but not in this instance.  In a previous post on Feed the Truth, I say:

 I was part of a team that suggested names for members of the group’s board.  Once Lubetzky set up the funding, he has had nothing further to do with the group.

From what I’ve been told, that is still true.  Feed the Truth does not have a website, in part because it is closing shop and not giving out more grants.  You can read about its earlier stages in Influence Watch,  Cause IQ, and Cision PR Newswire, but these are now out of date.

USRTK is doing important work and lots of it.  It’s worth following it.


Jul 19 2023

Ultra-processed pushback #3: Nordic Nutrition Researchers reply

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 12th 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: 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

Jul 18 2023

Ultra-processed pushback #2: The UK’s Scientific Advisory Committee

The U.K.’s Scientific Advisory Committee on Nutrition (SACN) has released its statement on ultra-processed foods.

It dealt with the NOVA classification system (the one I used in yesterday’s post to define ultra-processed foods).  The committee does not like it much.

Assessment beyond the initial screen identified that the literature is currently dominated by NOVA, raising the risk that any limitations or biases present within the NOVA classification system may be replicated throughout the research literature.
While NOVA also met criterion 2 on a clear, usable definition and criterion 4 on the availability of data on inter-assessor agreement, assessment beyond the initial screen dentified less certainty on the clarity, reliability and feasibility of the system.

The SACN’s conclusions:

The SRs identified have consistently reported that increased consumption of (ultra-) processed foods was associated with increased risks of adverse health outcomes. However, there are uncertainties around the quality of evidence available. Studies are almost exclusively observational and confounding factors or key variables such as energy intake, body mass index, smoking and socioeconomic status may not be adequately accounted for.

…In particular, the classification of some foods is discordant with nutritional and other food-based classifications. Consumption of (ultra-) processed foods may be an indicator of other unhealthy dietary patterns and lifestyle behaviours. Diets high in (ultra-) processed foods are often energy dense, high in saturated fat, salt or free sugars, high in processed meat, and/or low in fruit and vegetables and fibre.

…The observed associations between higher consumption of (ultra-) processed foods and adverse health outcomes are concerning – however, the limitations in the NOVA classification system, the potential for confounding, and the possibility that the observed adverse associations with (ultra-) processed foods are covered by existing UK dietary recommendations mean that the evidence to date needs to be treated with caution.

Comment: Kevin Hall  et al’s well controlled clinical trial of ultra-processed versus merely processed diets is neither discussed nor cited in this statement.  Once again, I have no personal knowledge of how this statement was developed, but the U.K.s Soil Association has published a statement with the provocative title, Sticky fingers of food industry on government ultra-processed food review.

While we’re pleased that SACN has prioritised this review, and has acknowledged that ultra-processed foods are of “concern”, we’re disturbed that the committee’s conclusions may have been skewed by industry ties, conflicted financial interests, and a narrow framing of the science.

…But the committee is also guilty of losing the wood for the trees, failing even to raise concern about how ultra-processed foods have overtaken their own nutritional advice….Most people in the UK are failing to eat such a [healthy] diet, precisely because these foods have been displaced by ultra-processed products. The average child’s diet is more than 60% ultra-processed, and rates of obesity and ill health are rising sharply in turn. …SACN is oddly silent on case for re-balancing the diet and addressing the corporate capture of children’s food.

These omissions should prompt us to look more closely at the composition of the committee. SACN has sixteen members. One is a paid consultant working for Cargill, Tate & Lyle, and CBC Israel (a manufacturer and marketer of fizzy drinks such as Coca-Cola and Sprite); two are in receipt of funding from the meat and dairy industry; one is a shareholder in Sainsbury’s; and five are members of the American Society of Nutrition, which is funded by Mars, Nestlé, and Mondelez. Among SACN’s members is the Chair of International Life Sciences Institute (ILSI) Europe, a body that receives funding from some of the world’s largest food companies, such as Barilla, Cargill, Danone, General Mills, Mondelez, and PepsiCo; and two individuals with financial relationships with the British Nutrition Foundation, an organisation funded by British Sugar, Cargill, Coca Cola, Danone, Greggs, Kellogg, KP Snacks, Mars, McDonald’s, Mondelez, Nestlé, PepsiCo, Tate & Lyle, and Tesco. Two SACN members have been funded by Danone, one of the largest ultra-processed food companies in the world; one sits on the council of the Nestlé Foundation; and another is a former employee of Unilever, with current shares in the company worth “more than £5000”.

These declared interests do not imply corruption or bias on the part of SACN members, but they illustrate how pervasive are industry ties at the interface of science and policy.

Jul 17 2023

Industry-influenced study of the week: Ultra-processed foods are good for you!

I am devoting this week to the pushback against advice to reduce consumption of ultra-processed foods.  It is coming from the food industry, of course, government agencies with ties to the food industry, and nutritionists who focus on  the benefits of nutrients, without contextualizing the foods and diets they come from (“nutritionism”).

For the record, ultra-processed foods are :

  • Industrially produced
  • Bear little resemblance to the foods they were derived from
  • Typically contain additives for color, flavor, and texture
  • Cannot be made in home kitchens,
  • Are formulated to be irresistable,
  • Are associated with excessive calorie intake and poor health
  • Are extremely profitable to their makers
  • Cannot be made in home kitchens (a brief operating definition)

Ultra-processed food pushback #1: A study from the USDA and authors with conflicted interests

The USDA’s Agricultural Research Service is so proud of this study that it sent out a press release.

Scientists at the USDA Agricultural Research Service’s (ARS) Grand Forks Human Nutrition Research Center led a study that demonstrates it is possible to build a healthy diet with 91 percent of the calories coming from ultra-processed foods (as classified using the NOVA scale) while still following the recommendations from the 2020-2025 Dietary Guidelines for Americans (DGA). The study highlights the versatility of using DGA recommendations in constructing healthy menus.

The Study: Dietary Guidelines Meet NOVA: Developing a Menu for A Healthy Dietary Pattern Using Ultra-Processed Foods.  Julie M. Hess, Madeline E. Comeau, Shanon Casperson, Joanne L. Slavin, Guy H. Johnson, Mark Messina, Susan Raatz, Angela J. Scheett, Anne Bodensteiner, Daniel G. Palmer.  The Journal of Nutrition, 2023.

Purpose: “The purpose of this proof-of-concept study was to determine the feasibility of building a menu that aligns with recommendations for a healthy dietary pattern from the 2020 DGA and includes ≥80% kcal from UPF as defined by NOVA.”

Method: “we first developed a list of foods that fit NOVA criteria for UPF, fit within dietary patterns in the 2020 DGA, and are commonly consumed by Americans. We then used these foods to develop a 7-d, 2000 kcal menu modeled on MyPyramid sample menus and assessed this menu for nutrient content as well as for diet quality using the Healthy Eating Index-2015 (HEI-2015).”

Results: “In the ultra-processed DGA menu that was created, 91% of kcal were from UPF, or NOVA category 4. The HEI-2015 score was 86 out of a possible 100 points.”

Conclusions: “Healthy dietary patterns can include most of their energy from UPF, still receive a high diet quality score, and contain adequate amounts of most macro- and micronutrients.”

 Conflicts of Interest: “MM serves as the Director of Nutrition Science and Research for the Soy Nutrition Institute (SNI) Global. The SNI Global receives funding from soybean farmers via the soybean national checkoff program and via membership dues from companies involved in manufacturing and/or selling soy ingredients and/or soyfoods. GHJ serves as Senior Advisor to the McCormick Science Institute. JLS serves on advisory/consultant boards for Simply Good Foods, Quality Carbohydrates Coalition, and the Sustainable Nutrition Scientific Board and has received funding from the National Institutes of Health, Taiyo, Barilla Foods, and the USDA in the past 12 mo. The other authors report no conflicts of interest.”

Funding: This work was supported by USDA Agricultural Research Service project grant #3062-51000-057-00D.

Comment:  I can think of only one reason for doing a study like this: to cast doubt on the concept of ultra-processed foods (UPF) and all the research showing that UPF diets induce people to eat more calories (see the study by Kevin Hall et al) and are strongly associated in hundreds of studies with poor health, evidence that by this time is overwhelming and incontrovertible.  Why now?  Because the 2025-2030 Dietary Guidelines Advisory Committee has been charged with examining the relationship of UPF to heart disease risk.

The first rule of the ‘Playbook” is to cast doubt on the research, which is what we are seeing here.  The message to reduce consumption of ultra-processed foods makes good sense for health reasons.  But such advice is very bad for the profits of food companies making junk foods.

The USDA’s Agricultural Research Service is a marketing arm of the food industry,.  It is heavily conflicted.

For one thing, the Healthy Eating Index is not useful for this purpose; it is strictly nutrient-based, which is not the issue here.  And the Dietary Guidelines are careful to leave plenty of room for eating junk foods and to say not one word about UPF.

I think the UPF concept is so solidly backed up by evidence that it is here to stay.  But it is so threatening to food companies making UPF products, and the USDA is so captured by the food industry (checkoff programs, anyone?) that it is understandable why they are so eager to cast doubt.

Thanks to the half dozen or so readers who sent this one to me, to Ted Kyle for calling it “oxymoronic healthy eating,” and  Kevin Hall for pointing out that the healthfulness of this diet is assumed, not tested: