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It’s pretty exciting when a major international science journal starts a satellite journal devoted to food issues.  Welcome to Nature Food.

I don’t say much about potentially harmful agricultural or other industrial chemicals in food for several reasons:

• There are so many of them—hundreds to thousands
• They are present in food in small amounts
• The extent of their harm is not well established

BUT (in capital letters because it is a bit one):

• They are not well regulated
• What is known about their health effects suggests harm

Studies of three chemicals illustrate these problems.

DICAMBA 

What it is: A herbicide used to kill broadleaf weeds that grow in fields of corn, wheat, and dicamba-tolerant soybeans.

Why it’s a worry: It can cause immediate toxic effects and might be carcinogenic.  It is highly volatile and can damage non-target plants through drifting, causing constant complaints from neighboring farmers.  The courts have overturned the EPA’s approval of dicamba use.  Even though the EPA admits dicamba has adverse effects on handlers as well as “birds, mammals, bees (larvae), aquatic plants and non-target terrestrial plants,” it is allowing existing stocks of dicamba to continue to be used.

The recent study: The headline: Alarming levels of weed killer found in study of pregnant women.  The study examined changes in the the number of pregnant women with dicamba in their urine and the amounts excreted from 2020-2012 to 2020-2022.  It found increases in both measures.

Conclusion: “Reliance on herbicides has drastically increased in the last ten years in the United States, and the results obtained in this study highlight the need to track exposure and impacts on adverse maternal and neonatal outcomes.”

PHTHALATES

What these are: Chemicals used to soften polyvinylchloride plastics.

The concern: Phthalates leach into food from plastic packaging materials.  They disrupt endocrine function.

The recent study:  Exposure to phthalates is associated with adverse birth outcomes such as decreased gestational age and increased risk of preterm birth.

Conclusion: “The $1·63–8·14 billion costs of preterm birth described here …add to the disease burden and costs of plastic in the USA, which were recently estimated to be $250 billion annually….Our findings also support individual behavioural interventions to reduce exposure. These include choosing personal care products labelled to be free of phthalates, and replacement of packaged foods with fresh foods.

CHLORMEQUAT

What this is: a plant growth regulator used on wheat, oats, and barley to decrease stem height, making the plants easier to harvest.

Why it’s a worry: Chlormequat has been linked to reduced fertility, altered fetal growth, and delayed puberty in animals.

The recent study: The headline: 80% of Americans test positive for chemical found in Cheerios, Quaker Oats that may cause infertility, delayed puberty.   The study found increasing amounts of this chemical in food and urine samples.

Conclusion: “These findings and chlormequat toxicity data raise concerns about current exposure levels, and warrant more expansive toxicity testing, food monitoring, and epidemiological studies.”

Comment: These are only three of all the chemicals out there that get into our food and appear in our bodies.  Yes, more research is needed to find out just how harmful they are.  But I see no evidence that they are good for us.  I think we need:

• Much greater urgency and attention from FDA and EPA on getting these chemicals out of the food supply
• More information about how to avoid the chemicals, especially in pregnant women and young children
• Coalition advocacy for more stringent regulation (the Environmental Working Group is doing a great job but cannot do this alone)

The FDA issued its most recent report on antibiotics late last year: 2022 Summary Report On Antimicrobials Sold or Distributed for Use in Food-Producing Animals, along with Antimicrobial Sales and Distribution Data 2013-2022.

It did this in response to public concerns about antibiotic use in food animals: if antibiotics are used at subtherapeutic doses, they might induce microbial resistance to drugs used to treat diseases in humans.

This is not a theoretical concern.  It’s a real problem.

It’s also a problem because the vast majority of antibiotics were used as growth promoters or to prevent infections in animals crowded together—not to treat disease.

In 2014 or so, the FDA ruled that medically important antibiotics could no longer be used as growth promoters in farm animals.  That rule went into effect in 2017.

The FDA’s good news: the amounts of antibiotics used in farm animals has declined since then.

Are medically important antibiotics still used for non-therapeutic purposes?

The report says that since 2017, zero antibiotics are administered for growth promotion.

If you wonder whether this is really true (as I do), consider that $11.2 million kilograms of antibiotics were used in food animals in 2022.  This is a decrease from the 15.6 million kg used in 2015, but still a lot.

Of these drugs, 63% are administered in feed, and 31% in water.

All antibiotics still used as growth promoters are supposed to be drugs not used in human medicine.

I’m not the only skeptic on this one.  See:

I.  The Bureau of Investigative Journalism’s Antibiotics in agriculture: The blurred line between growth promotion and disease prevention.

In an investigation published today, the Bureau revealed how US farm animals are still being dosed with antibiotics vital to human health, despite efforts to curtail such usage and combat the spread of deadly superbugs. We also found that a regulatory loophole means that using antibiotics to make animals fatter – a process known as growth promotion – is technically still possible, despite this practice being banned in January 2017.

II.  Nature: Antibiotic use in farming set to soar despite drug-resistance fears. Analysis finds antimicrobial drug use in agriculture is much higher than reported.

III.  Vox: Big Meat just can’t quit antibiotics: Meat production is making lifesaving drugs less effective. Where’s the FDA?

According to an analysis published in September by the Natural Resources Defense Council and One Health Trust, medically important antibiotics are increasingly going to livestock instead of humans. In 2017, the meat industry purchased 62 percent of the US supply. By 2020, it rose to 69 percent.

Does the FDA check?  It has guidance for industry on The Judicious Use of Medically Important Antimicrobial Drugs in Food-Producing Animals, but this guidance is non-binding.

Obviously, the FDA needs to do more.  Its officials told Vox:

I was surprised to see a press release from the American Society for Nutrition (ASN—of which I am a member) announcing publication of a research paper the Society had commissioned and published on sugars and body weight: Important food sources of fructose-containing sugars and adiposity: a systematic review and meta-analysis of controlled feeding trials.

The paper, the press release said, “Illustrate[s] The Need for Nuance in Public Health Guidance Related to Consumption of Sugars: Findings call into question recommendations that imply all sources of fructose-containing sugars carry the same risk.”

The press release notes that “this comprehensive review is timely as the 2025 Dietary Guidelines Advisory Committee currently assesses the latest science to inform updated evidence-based recommendations,” and it quotes the lead author: “There is an opportunity for more food-based guidance around sugars to help ensure Americans don’t inadvertently eat less health-promoting foods containing fructose – especially at a time when most people don’t eat enough of all forms of fruit, which offer significant health benefits.”

Uh oh.  This is an easily misinterpreted message.

My immediate question:  Who wrote the paper ?

No surprise.: authors with extensive conflicts of interest.

I’ve written about some of these authors’ conflicts of interest disclosures previously.  See, for example. this, this, and this.

Just for fun, I’ll post this particular statement of the conflicted interests at the end of this post.

Basically, these authors do not understand the difference between a conflict of interest (financial ties, which are discretionary) and non-discretionary viewpoints (all researchers have them).  In this case, consulting for a sugar company is a conflict; being a vegan or avoiding sugar-sweetened beverages is not.

My second question: Why did ASN commission this paper, and from these particular authors no less?

I contacted John Courtney, the long-time executive director of the ASN.  He said this was a leftover from an initiative started ten years ago.  Since then, the ASN has decided not to commission papers on controversial topics and this will not happen again.

Good.  It shouldn’t.  Commissioning papers like these make the ASN look like an arm of the food industry.  The ASN should avoid even teh appearance of conflicts of interest as much as it possibly can.

You don’t believe this is a problem?  Take a look at this conflict of interest statement.  Enjoy!

So many readers have asked me to comment on the American Academy of Pediatrics’ Clinical Practice Guideline for the Evaluation and Treatment of Children and Adolescents With Obesity that I thought I ought to say something about it.

The guideline report is so long and detailed that I cannot imagine anyone actually reading it.  I started with the introduction, which summarizes basic facts.

• 14.4 million children and adolescents are affected by obesity.
• Obesity is a chronic disease with potentially serious health consequences
• Childhood obesity is strongly affected by social determinants of health (poor education, poverty, racism, exposure to toxins, etc)
• Childhood obesity is stigmatized in ways that fail to acknowledge social determinants.

What got press attention—and the attention of readers of this blog—is the AAP’s endorsement of drug and bariatric surgical treatment of obese children.

I cut right to the chase and looked at Appendix I, which gives the AAP’s algorithm for deciding on treatment options.  

The report’s major conclusions expand on this chart (the report does not define KAS, but I think it means Knowledge, Attitudes, and Skills):

KAS 9.  Pediatricians and other PHCPs should treat overweight (BMI ≥ 85th percentile to <95th percentile) and obesity (BMI ≥ 95th percentile) in children and adolescents, following the principles of the medical home and the chronic care model, using a family-centered and nonstigmatizing approach that acknowledges obesity’s biologic, social, and structural drivers.

KAS 10.  Pediatricians and other PHCPs should use motivational interviewing (MI) to engage patients and families in treating overweight (BMI ≥ 85th percentile to <95th percentile) and obesity (BMI ≥ 95th percentile).

KAS 11.  Pediatricians and other PHCPs should provide or refer children 6 y and older (Grade B) and may provide or refer children 2 through 5 y of age (Grade C) with overweight (BMI ≥ 85th percentile to <95th percentile) and obesity (BMI ≥ 95th percentile) to intensive health behavior and lifestyle treatment. Health behavior and lifestyle treatment is more effective with greater contact hours; the most effective treatment includes 26 or more hours of face-to-face, family-based, multicomponent treatment over a 3- to 12-mo period.

KAS 12.  Pediatricians and other PHCPs should offer adolescents 12 y and older with obesity (BMI ≥ 95th percentile) weight loss pharmacotherapy, according to medication indications, risks, and benefits, as an adjunct to health behavior and lifestyle treatment.

KAS 13.  Pediatricians and other PHCPs should offer referral for adolescents 13 y and older with severe obesity (BMI ≥ 120% of the 95th percentile for age and sex) for evaluation for metabolic and bariatric surgery to local or regional comprehensive multidisciplinary pediatric metabolic and bariatric surgery centers.

What is not in this guideline is anything that addresses the social determinants of childhood obesity.  What we have here is a focus on treating the symptoms, but getting nowhere near the cause.

It is difficult for someone like me who is not affected by those determinants to even imagine how drugs and surgery could be thought even remotely acceptable for children, even those over the age of 12, but I am not treating these kids.

Providers who do treat obese children tell me they are relieved to be able to offer options that might help kids achieve healthier weights.

As I see it, these should be absolute last resorts if used at all. And this is without even getting into issues of cost or our dysfunctional health care system.

In public health terms, drugs and surgery are “downstream” solutions to a problem that began way upstream with all those societal determinants.

If ever we needed upstream approaches, chldhood obesity is a prime example.

Upstream means policy changes that make healthy eating more appealing, accessible, and affordable  That’s what pediatricians need to be calling for.

This AAP report deliberately separates treatment from prevention.  It promises a discussion of prevention in a subsequent report.  I hope it is as hard hitting as any AAP report has ever been.

If childhood obesity teaches us anything, it is that our society needs to change in ways that are healthier for our children.

Additional supporting documents

• Executive Summary: Clinical Practice Guideline for the Evaluation and Treatment of Children and Adolescents With Obesity
• Appraisal of Clinical Care Practices for Child Obesity Treatment. Part I: Interventions
• Appraisal of Clinical Care Practices for Child Obesity Treatment. Part II: Comorbidities

Thanks to all the people who wrote me about this.  Much appreciated.

*******

For 30% off, go to www.ucpress.edu/9780520384156.  Use code 21W2240 at checkout.

Thanks to Lynn Ripley for this gem.

Who knew that herbal dietary supplements are now marketed for cows, with claims that they improve milk quality and yield and reduce methane emissions at the same time?  Not me, for sure.

The producer of this supplement says feeding a dairy cow one gram a day will produce these benefits. That’s not much for a 1500-2000 pound dairy cow, even feeding the gram a day for at least four weeks (which is what the manufacturer says you have to do).

This, to say the least, is hard to believe.

As evidence, the manufacturer, Agolin Ruminant, cites three studies of its supplement.   Want to take a guess as to who funded all three of them?  Bingo!  Agolin Ruminant.

My first question: what is in Agolin Ruminant that is so powerful that only one gram a day will produce measurable benefits?

This question is not easy to answer.

The manufacturer’s statement of product information says only:

AGOLIN RUMINANT L is a carefully balanced combination of essential oil compounds in their natural / nature-identical form. All active substances are of high purity and are accepted for use under current European animal feed and human food legislation.

In the meta-analysis summarized below, the authors say:

The main active compounds of this product are food grade and chemically-defined plant extracts including coriander (Coriandrum sativum) seed oil (up to 10%), eugenol (up to 7%), geranyl acetate (up to 7%) and geraniol (up to 6%) along with some preservatives such as fumaric acid.

Those account for 30% of what’s in the product.  The other 70%?  A mystery.

This supplement is a feed additive.  Animal feed products do not require the level of ingredient disclosure required for dietary supplements.  The manufacturer says all ingredients are either FDA-approved or Generally Recognized as Safe (GRAS).  All are plant extracts (available from cloves or geraniums, for example).   Great.  I’d like to know what they are.

The manufacturer points to an endorsement from the Carbon Trust for the value of this product for reducing methane emissions.

This opinion is based on academic references, published scientific papers and field reports and joins the conclusions of the independent meta analyses from A. Belanche et al.

Oh dear.  The Carbon Trust did not do its homework.  The article by Belanche et al, is anything but independent.

Here are the key studies attesting to the purported benefits of this supplement for cows, starting with Belanche et al.

I.  A Meta-analysis Describing the Effects of the Essential oils Blend Agolin Ruminant on Performance, Rumen Fermentation and Methane Emissions in Dairy Cows. Alejandro Belanche, Charles J. Newbold, Diego P. Morgavi, Alex Bach, Beatrice Zweifel and David R. Yáñez-Ruiz.  Animals 2020, 10, 620; doi:10.3390/ani10040620

Conclusion: This meta-analysis combining 23 experimental and farm studies across 10 different countries indicated that supplementation of lactating dairy cows with the essential oils blend Agolin Ruminant® (at 1g/d per cow) exerted positive effects on milk production whereas it decreased enteric methane emissions in comparison to un-supplemented cows. These effects mostly appeared after an adaptation period of approximately 4 weeks of treatment and consisted in an increase in fat and protein corrected milk suggesting an improved feed utilization.

Funding: This research received no external funding.

Acknowledgments: This study was supported by Agolin SA (Bière, Switzerland).

Conflicts of Interest: Author B.Z. was employed by the company Agolin SA but had no role in the design, execution, interpretation, or writing of the meta-analysis. 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:  Really?  Even though the authors cite support by Agolin SA?

II.  The Impact of Essential Oil Feed Supplementation on Enteric Gas Emissions and Production Parameters from Dairy Cattle Angelica V. Carrazco, Carlyn B. Peterson, Yongjing Zhao, Yuee Pan , John J. McGlone, Edward J. DePeters and Frank M. Mitloehner.  Sustainability 2020, 12, 10347; doi:10.3390/su122410347

Conclusion: Cows supplemented with Agolin versus the control had less methane intensity (g/period/kg
energy-corrected milk (ECM); p = 0.025).

Funding: This study was funded by Agolin (Agolin SA, Bière, Switzerland) and by Feedworks USA Ltd. (Ohio, USA).

Conflicts of Interest: The sponsor played no role in the execution and interpretation of the data and preparation of the present manuscript. The authors declare no conflict of interest.

III.  Evaluation of Agolin®, an Essential Oil Blend, as a Feed Additive for High Producing Cows.  Peter Williams1, John Clark, Kelly Bean  Open Journal of Animal Sciences, 11, 231-237. https://doi.org/10.4236/ojas.2021.112018

Conclusion: The trial showed that Agolin assisted in improving production parameters of economic importance to dairy producers.

Conflict of Interest: Mr. John Clark and Mr. Peter Williams market Agolin in the United States of America. Both were involved in the design but not the analysis of data or interpretation of results.

Comment

These are industry-funded supplement studies designed to sell a supplement of dubious benefit (my interpretation) to dairy producers to convince the public that they are doing all they can to reduce methane emissions.

The supplement doesn’t cost much per dose, but there are lots of dairy cows that have to be given the supplement for at least four weeks.

Without even getting into the details of the measurement difficulties or the overall science, two things are particularly troubling:

• The lack of transparency about ingredients
• The lack of a convincing mechanism of action

Call me skeptical.  I don’t see this supplement as a solution to the methane emission problem caused by ruminants.