Food Politics

by Marion Nestle
Jun 12 2024

Interesting paper of the week II. History of obesity

There is much discussion these days of the complexity of causes and consequences of excessive gain body fat.  This review addresses the history of what is known—and not known—about obesity., by someone who has been studying it for decades.

Bray GA. Obesity: a 100 year perspective. Int J Obes (Lond). 2024 May 7. doi: 10.1038/s41366-024-01530-6.

His conclusion:

Obesity is both a public health issue and an individual challenge
As noted during the discussion of the Fogarty Center Conference in 1973, the public health community was already aware of the health-related risks associated with obesity even before the explosion in prevalence occurred after 1975. The ensuing pandemic of obesity with some people developing obesity, but not others, challenges modern medicine and public health. As Hippocrates said more than 2500 years ago: “Life is short, art long, opportunity fleeting, experience treacherous, judgment difficult.” The challenge for those of us working in the field of obesity is that there is more to uncover to fully understand and be able to effectively treat people with obesity.

The paper has 137 references.  If you want to learn what the debates are about, this is a great place to begin.

Jun 11 2024

Interesting study of the week I: diet and Alzheimer’s

This seems to be a slow news week so I’m going to get caught up on research papers I think worth reading.

I first heard about this study from this video, from Dr. Greger’s newsletter announcement (I subscribe).

Here’s the study: Ornish D, et al.  Effects of intensive lifestyle changes on the progression of mild cognitive impairment or early dementia due to Alzheimer’s disease: a randomized, controlled clinical trial.  Alzheimer’s Research & Therapy volume 16, Article number: 122 (2024).

It put 50 or so people in their 70s or older on “an intensive multidomain lifestyle intervention compared to a wait-list usual care control group” for 20 weeks.

People on the lifestyle intervention—diet, exercise, stress management, group support—did better.

The first author, Dean Ornish, runs a lifestyle modification program.

Comment: Wouldn’t this be terrific!  At the very least it is further evidence for the health benefits of a largely (not necessarily exclusively) plant-based diet.  Eating plant foods is strongly associated with prevention of any number of undesirable conditions.  The Alzheimer’s Association already recommends the DASH or Mediterranean diet patterns; both are plant based.

Eat your veggies.  Do so cannot hurt and might help—a lot.

Jun 10 2024

Industry-influenced study of the week: probiotics and vaginal microbiome

I learned about this study from this account.

Probiotics may improve vaginal microbiota in postmenopausal women: A specific combination of probiotic strains may restore vaginal microbiota and relieve vaginal distress in postmenopausal women, according to a new study from Italian probiotic manufacturer SynBalance…. Read more

High marks to indicating industry sponsorship right up front.

The study: Efficacy of Lactiplantibacillus plantarum PBS067, Bifidobacterium animalis subsp. lactis BL050, and Lacticaseibacillus rhamnosus LRH020 in the Amelioration of Vaginal Microbiota in Post-Menopausal Women: A Prospective Observational Clinical Trial. Nutrients 2024, 16(3), 402;

Method: “Subjects were supplemented with a probiotic product containing Lactiplantibacillus plantarum PBS067 (DSM 24937), Bifidobacterium animalis subsp. lactis BL050 (DSM 25566), and Lacticaseibacillus rhamnosus LRH020 (DSM 25568; all from SynBalance Srl, Origgio, Italy)…Women were asked to consume 1 capsule/day, away from meals, for 4 consecutive weeks. Assessments of health status were carried out at the starting point of the study (T0), after 4 weeks of oral probiotic supplementation (T1), and after a 4-week follow-up.”

Results: “Clinical outcomes revealed a decrease in menopausal symptoms. Significant improvements were observed across various parameters…Moreover, the probiotic intervention facilitated the restoration of vaginal microbiota, evidenced by an increase in lactobacilli abundance.

Conclusion: “the combination of these specific probiotic strains, previously clinically tested in childbearing-age women, showed to be effective also for post-menopausal women.”

Conflicts of Interest: “Authors P.M. and D.F.S. were employed by the company Synbalance Srl. Authors E.V., A.M. and A.C. were employed by the company Wellmicro Srl. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.”

Comment: Employees of the company making the probiotic supplement conducted this uncontrolled observational study.  The supplement made study subjects feel better and improved their microbiomes.  But compared to what?  The study had no control group.

In addition:  While we are on the subject of probiotics, I’m quoted in a New York Times article about probiotic supplements in beverages.

Prebiotic sodas aren’t likely to harm your health, Dr. Nestle said, but it’s also not likely that they’ll be beneficial.

“Really, if people are concerned about their microbiome, they need to eat vegetables,” Dr. Nestle said. “Vegetables would do wonders.”

Jun 7 2024

Weekend viewing: Roots So Deep

At long last, Peter Byck’s Roots So Deep is available for viewing.

Peter is at Arizona State.  He’s done something quite remarkable, so much so that I wrote a blurb for his films.

If we are going to do anything to prevent further climate change, soil degradation, and groundwater pollution, we are going to have to transform current agricultural practices to those that are more regenerative.

Roots So Deep compares methods used by conventional and regenerative and shows how farmers—real people—are trying to make either method work.

Peter Byck is a terrific interviewer, even of people who view the world from different perspectives.  His question: what will it take to convince farmers to convert from conventional to regenerative?

The films make it clear that conversion won’t come easily—it appears too risky and requires too much of a change from using fertilizers and tilling methods.  But once farmers take that risk, we can see how they win on productivity, financial viability, soil quality, and resistance to flooding and climate.

What I like so much about these films is the genuine compassion and understanding shown for farmers, no matter how they farm.  Anyone who wants to know what regenerative agriculture, in theory and in practice, will watch these films with pleasure and admiration for the hard work that goes into producing food.

Enjoy!  And pass the word along.

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 5 2024

Dietary guidelines II. Where is rigorous nutrition research?

In considering the effects of ultra-processed foods, the Dietary Guidelines Advisory Committee (DGAC) only dealt with observational research.

It excluded what I consider the most important study ever done to explain weight gain: the  controlled clinical trial of ultra-processed versus processed diets done at NIH in 2019.

This study is hugely important for four reasons:

  1. The ultra-processed and minimally processed diets were matched for nutrients and palatability; study subjects could not tell which was which.
  2. Study subjects were in a metabolic ward, imprisoned; they could not lie or cheat about what they ate.
  3. The investigators were trying to disprove the idea that ultra-processed foods do anything special.
  4. The results were unambiguous; subjects ate 500 calories more on the ultra-processed diets; this is an enormous difference; studies rarely show anything like this.

The DGAC was instructed to ignore this study because it only lasted 4 weeks.  This is a travesty.

But it is not the only travesty.

NIH has chosen to cut the capacity of the metabolic facility.  It has reduced the number of beds to seven, shared among investigators, and allowing Hall only two beds at a time.  This means any study with enough subjects to meaningfully answer questions has to be done two at a time, taking many months or years.

As a Senate Committee said in a recent report: NIH In the 21st Century: Ensuring Transparency and American Biomedical Leadership,


Writing in Politico a year or so ago, Helena Bottemiller Evich said:

Take NIH. In 2018, the agency invested $1.8 billion in nutrition research, or just under 5 percent of its total budget. USDA’s Agricultural Research Service spends significantly less; last year, the agency devoted $88 million, or a little more than 7 percent of its overall budget, to human nutrition, virtually the same level as in 1983 when adjusted for inflation. That means USDA last year spent roughly 13 times more studying how to make agriculture more productive than it did trying to improve Americans’ health or answer questions about what we should be eating.

Nutrition science has become such a low priority at NIH that the agency earlier this year proposed closing the only facility on its campus for highly controlled nutrition studies.

What’s going on?  Why aren’t NIH and USDA doing everything possible to help prevent obesity and its consequences.  Chronic diseases are leading causes of death and disability.  Three quarters of American adults are overweight.  The American public needs help.

Shouldn’t research on chronic disease be a major national priority?

Shouldn’t NIH be doing everything possible to answer questions about ultra-processed foods?

Kevin Hall explained the need in Science in 2020:

investment in research facilities for domiciled feeding studies could provide the infrastructure and staff required to simultaneously house and feed dozens of subjects comfortably and safely. One possibility would be to create centralized domiciled feeding facilities that could enable teams of researchers from around the world to recruit a wide range of subjects and efficiently conduct rigorous human nutrition studies that currently can only be performed on a much smaller scale in a handful of existing facilities.

I think yes.

The DGAC report called for research that

Tests the effects of dietary patterns with UPF that are matched for energy-density but vary in diet quality in relation to health outcomes, preferably using well-controlled trials in the U.S.

If the DGAC needs that research, NIH should insist on and enthusiastically support such studies.

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 .

Jun 3 2024

Industry-funded study of the week: Pork

A reader, Tara Kenny, sent me this one.  She wrote that she had seen a chart from this paper posted on X (Twitter) “showing  how pork, chicken, eggs, fish and turkey are almost the same as beans and nuts in terms of mean GHGs/50g of protein so I figured this paper would have likely have some conflicts of interests…It does.”

I went right to it.

  • The paper: Perspective: The Place of Pork Meat in Sustainable Healthy Diets. Advances in Nutrition.  Adam Drewnowski.  Advances in Nutrition.  Volume 15, Issue 5, May 2024, 100213.
  • Rationale. “The present analyses explore the place of pork in sustainable healthy diets worldwide, given the need for high-quality protein and the predictable patterns of global food demand.”
  • Method: “This Perspective article aims to assess the place of fresh pork in the global sustainability framework, drawing on data from United States sources and from international agencies. The present goal was to examine the sustainability of pork as a source of meat protein, considering nutrition, affordability, environmental impact, and future food demand.”
  • Conflict of interest: “AD is the original developer of the Naturally Nutrient Rich (NNR) and the Nutrient Rich Food (NRF) nutrient profiling models and a member of scientific advisory panels for The National Pork Board, Nestlé, FrieslandCampina, BEL, and Carbohydrate Quality Panel supported by Potatoes USA and has worked with Ajinomoto, FoodMinds, KraftHeinz, Nutrition Impact LLC, Nutrition Institute, PepsiCo, and Samsung on quantitative ways to assess nutrient density of foods.”
  • Funding: “Analyses of publicly available USDA, FAO, and World Bank data were supported by the National Pork Board. The funders were not involved in the development of databases, analytical models, data analysis or interpretation, manuscript preparation or the decision to submit the manuscript for publication.”

Comment: Reducing greenhouse gas emissions produced by agriculture is an important goal.  Most researchers think industrialized countries should produce less meat (particularly beef) as a necessary first step.  This analysis suggests we stop worrying about the effects of pork on climate change (never mind the effects of industrial pork production on air, land, and water within smelling distance). This article, by my old friend and colleague Adam Drewnowski, is an excellent overview of pork nutrition.  But why do it?  The title alone raises the question, “Who paid for this?”