by Marion Nestle

Currently browsing posts about: Conflicts-of-interest

Dec 6 2021

Industry-funded review of the week: dairy foods and inflammation

My thanks go to New Zealand reader Kirsten for sending this one.

The study: Exploring the Links between Diet and Inflammation: Dairy Foods as Case Studies. Julie M Hess, Charles B Stephensen, Mario Kratz, Bradley W Bolling.  Advances in Nutrition, Volume 12, Issue Supplement_1, October 2021, Pages 1S–13S,

Note: This article was intended as a review article based on presentations made by CBS, MK, and BWB at the American Society for Nutrition 2020 LIVE ONLINE Conference 7–10 June 2020.

Background: Systemic chronic inflammation may be a contributing factor to many noncommunicable diseases, including diabetes, cardiovascular disease, and obesity. An emerging body of evidence indicates that consuming certain foods, including dairy foods like milk, cheese, and yogurt, may be linked to a decreased risk for inflammation.

Method: Review of research on dairy foods and inflammation.

Conclusion: While there is currently insufficient evidence to prove an “anti-inflammatory” effect of dairy foods, the substantial body of clinical research discussed in this review indicates that dairy foods do not increase concentrations of biomarkers of chronic systemic inflammation.

Funding: The ASN Nutrition 2020 session that this article is based on was supported by the National Dairy Council. This support included honoraria for MK and BWB. The authors reported no funding received for this study.

Author disclosures: JMH was an employee of the National Dairy Council at the time this article was written. MK has received honoraria and reimbursements of travel costs as well as research funding from dairy-related organizations, including the National Dairy Council, Dairy Management, Inc., Dairy Farmers of Canada, the Dutch Dairy Organization (Nederlandse Zuivel Organisatie), Dairy Australia, and the French Dairy Interbranch Organization (CNIEL). BWB has received research funding for dairy-related projects from University of Wisconsin Dairy Innovation Hub, the National Dairy Council, and USDA National Institute of Food and Agriculture (NIFA) HATCH WIS02094. The other author reports no conflicts of interest.

Comment: This is a study by dairy-funded authors with an interesting spin.  The research review found no anti-inflammatory effect of dairy foods but concludes that they have a benefit: they don’t make inflammation worse.  I realize that dairy foods have a bad reputation among some eaters, but I wish the dairy industry didn’t sponsor research so blatantly in its self-interest.  I also wish we could get away from one-food research.  One food cannot possibly make a substantial difference in the diets of reasonably healthy people who eat a variety of foods.  I am all for eating dairy foods if you like them, especially from well-treated animals.  They have a place in healthful diets—or not ,if you don’t like or want to eat them.

Reference: For a summary of research on the “funding effect”—the observation that research sponsored by food companies almost invariably produces results favorable to the sponsor’s interests but that recipients of industry funding typically do not recognize its influence—see my book, Unsavory Truth: How Food Companies Skew the Science of What We Eat.

Nov 29 2021

Conflicted study of the week: mushroom patents?

A reader in Norway, Marit Kolby, sent me this one.

First, the press release: “Mushroom consumption may lower risk of depression.”

New research led by Penn State College of Medicine also reveals that these superfoods may benefit a person’s mental health.  Penn State researchers used data on diet and mental health collected from more than 24,000 U.S. adults between 2005 and 2016. They found that people who ate mushrooms had lower odds of having depression.

The study: Mushroom intake and depression: A population-based study using data from the US National Health and Nutrition Examination Survey (NHANES), 2005–2016Djibril M.Ba. XiangGao, LailaAl-Shaar, Joshua, E.Muscat, Robert B.Beelman, John P.RichieJournal of Affective Disorders, Volume 294, 1 November 2021, Pages 686-692.

Hypothesis: “We hypothesized that mushroom consumption is associated with a lower risk of depression in American adults.”

Method: Analysis of dietary recall data from NHANES vs. self-reported depression.

Conclusion: “Mushroom consumers had a lower odd of depression. However, we did not observe a dose-response relationship.”

Funding: none.

Declaration of competing interest: none.

Comment: Ordinarily, beyond noting the conditional “may be linked” (which also could be “may not”  and the lack of dose-response, I would not bother to comment on this study except that Marit Kolby wrote:

As usual, the health effects (this time from mushrooms) are greatly exaggerated, especially given the study type and the lack of a dose-response relationship.  One compound in mushrooms suggested to explain the association is ergothioneine. The authors list no conflicts of interest.  But look at the patent list of the author Beelman.

This called for a look at the patent list.  Beelman does indeed hold several patents related to ergothioneine from mushrooms, but most of them are assigned to the Penn State Research Foundation.   This is not unusual for universities, but called for a look at Penn’s State’s policy on faculty intellectual property.

Penn State’s policy on patents requires research faculty to negotiate patent income according to a formula.

  1. PSRF [the foundation]: 40%
    Inventor(s): 40%
    Administrative Unit of College: 20%
  2. The inventors’ portions of the income are divided according to the contribution percentage that the inventors establish. A memo to establish the percentages to be paid to each invention will be sent to the Inventors before making payment .

Without knowing the details of Beelman’s arrangement with the university, it is difficult to be sure that a conflict of interest exists (he might have turned all the proceeds over to the university), but this situation clearly gives the appearance of a conflict, and an undisclosed one at that.

If professor Beelman is entitled to any percentage of profits from the patents, he has a competing interest and should have disclosed it.

Regardless, his declaration should have acknowledged his patent ownerships, as should the university’s press release.

Are mushrooms a “superfood” as the press release maintains?

Marit Kolby thinks it is more likely that mushrooms are an indicator of usual consumption of whole rather than ultra-processed foods, and points out that a couple of studies have linked ultra-processed foods themselves to depression.

Nov 15 2021

Industry-funded study of the week: would you believe baobab?

I learned about this study from an article in FoodNavigator.com, “Baobab industry welcomes study linking the fruit to good gut health.”

The title raised the question, “Who funded this?”  Bingo, as it turns out.

Baobabs are enormous African trees that produce a highly fibrous fruit.

I can’t say it looks particularly yummy.  In fact, it is described as “floury, dry, and powdery” and works best as a powdered ingredient.

But the baobab industry?  Who knew such an entity existed?

It does.  Hence this study:

The study: A Pectin-Rich, Baobab Fruit Pulp Powder Exerts Prebiotic Potential on the Human Gut Microbiome In VitroMartin FoltzAlicia Christin ZahradnikPieter Van den AbbeeleJonas GhyselinckMassimo Marzorati.  Microorganisms. 2021 Sep 17;9(9):1981.

Methods: Test tube mixing of baobab powder with colonic bacteria.

Results: Baobab fruit pulp powder boosted colonic acidification across three simulated human adult donors due to the significant stimulation of health-related metabolites.

Conclusions: Overall, Baobab fruit pulp powder fermentation displayed features of selective utilization by host microorganisms and, thus, has promising prebiotic potential.

Funding: The studies described in this manuscript were performed at the request of and were funded by Döhler, 94295 Darmstadt, Germany  Surprise!  This company makes baobab powder.

Conflict of interest:  M.F. and A.C.Z. are employees of Döhler. While M.F. participated in the design of the study, the interpretation of the data, and the revision of the manuscript, M.F. did not participate in the collection and analyses of data.

Comment: No food, product, or ingredient is too obscure to avoid industry attempts to demonstrate that it can be marketed as a “superfood” (see, for example, this product).

Reference: For a summary of research on the “funding effect”—the observation that research sponsored by food companies almost invariably produces results favorable to the sponsor’s interests but that recipients of industry funding typically do not recognize its influence—see my book, Unsavory Truth: How Food Companies Skew the Science of What We Eat.

Oct 25 2021

Industry-funded study of the week: Would you believe Jackfruit?

Jackfruit?  No, I’m not kidding.

For one thing, it’s JSTOR Daily’s Plant of the Month: “The newly hot alternative to meat has a long history.”

Jackfruit is not new in South Asia and its surrounding regions, where it has been a culturally significant foodstuff for centuries. Nor is jackfruit new in the West. Rather, it has a long and disquieting history: British imperialists wielded jackfruit as a tool to provide cheap nutrition to enslaved and coerced laborers throughout their empire.

Here’s what it looks like on the tree:

Type 2 diabetes: Add green unripe jackfruit flour to your daily meal plan, it may help control Type 2 diabetes - The Economic Times

And off:

Fresh Jackfruit - Shop Fruit at H-E-B

If you are in the business of selling Jackfruit, or products made from it, you will want research demonstrating health benefits.

Voila!

The study: Efficacy of green jackfruit flour as a medical nutrition therapy replacing rice or wheat in patients with type 2 diabetes mellitus: a randomized, double-blind, placebo-controlled study  Gopal Rao, K. Sunil Naik, A. G. Unnikrishnan & James Joseph.  Nutrition & Diabetes volume 11, Article number: 18 (2021)

Methods: This was a randomized, double-blind, placebo-controlled study of patients with type-2 diabetes who were being treated with oral antihyperglycemic agents.  They were either given jackfruit flour 30 g/day (Group A) or placebo flour (Group B) for 12 weeks.

Results: Patients from Group A had a better reduction in glycosylated hemoglobin, fasting plasma glucose, and postprandial plasma glucose than patients in Group B.

Conclusion: This study demonstrates the efficacy of jackfruit flour in glycemic control as medical nutrition therapy replacing an equal volume of rice or wheat flour in daily meal.

Funding: Diet Fibre 365 Food Products Pvt Ltd, India.

Acknowledgment: “The authors would like to acknowledge Abiogenesis Clinpharm Pvt Ltd, Hyderabad, for medical writing assistance funded by Diet Fibre 365 Food Products Pvt Ltd, Mumbai, India.”

Competing interests: JJ is the inventor of Jackfruit 365™ Green Jackfruit Flour with a pending patent and CEO of God’s Own Food Solutions Pvt Ltd which along with its subsidiary Diet Fibre 365 Food Products Pvt Ltd manufactures and markets the product. AGR, KSN, and UAG have no conflict of interest to declare.

Comment: This is a classic example of the funding effect in nutrition research.  The author owns the Jackfruit flour and the company that markets it, and the funder wrote (OK, helped to write) the paper.  The results were predictable.

Reference: For a summary of research on the “funding effect”—the observation that research sponsored by food companies almost invariably produces results favorable to the sponsor’s interests, but that recipients of industry funding typically do not recognize its influence—see my book, Unsavory Truth: How Food Companies Skew the Science of What We Eat.

Oct 4 2021

Industry-sponsored study of the week: glyphosate (Roundup) in food

Thanks to Tufts Professor Sheldon Krimsky for sending me this gem.

Residues of glyphosate in food and dietary exposure.  John L. Vicini,Pamela K. Jensen,Bruce M. Young,John T. Swarthout, Comprehensive Reviews in Food Science and Food Safety.  First published: 16 August 2021.

The study: A review of existing data on amounts of glyphosate residues in foods as compared to maximum limits or tolerances set by European or American regulatory agencies.  The study also reviewed data on levels of glyphosate in urine samples.

Conclusion: “Exposures to glyphosate from food are well below the amount that can be ingested daily over a lifetime with a reasonable certainty of no harm.”

Conflicts of interest:  “The authors are all employees of Bayer Crop Science, a major manufacturer of glyphosate.”
Comment: Glyphosate is used to kill weeds on fields of genetically modified crops, most notably corn and soybeans, but also other crops engineered to resist its action.  US farmers use a lot of it—300 million pounds a year on average.  Glyphosate has been linked to cases of non-Hodgkin lymphoma in people exposed to large amounts.  Its maker, Bayer Crop Science, settled these cases for billions of dollars last year.  It also said it would stop selling glyphosate for home use.  Bayer wants you to stop worrying about glyphosate residues in your food.  Hence, this publication.
Here’s what the FDA says about what it’s doing to protect us from glyphosate in food.
Here’s what a law firm says about which foods have glyphosate residues.
What can you do to avoid glyphosate?
  • Don’t use it in your garden or around your house.
  • Eat a wide variety of minimally processed whole foods; most are unlikely to have been sprayed directly.
  • Minimize intake of highly processed foods made with soy and corn ingredients.

And encourage the EPA to set firm standards and the FDA to continue to monitor foods for glyphosate residues.  Its last report was in 2017.

Sep 27 2021

Industry-sponsored study of the week: walnuts

I learned about this one from an article in FoodNavigator: Study: Walnut consumption linked to improved life expectancy

New research from the Harvard T.H. Chan School of Public Health funded by the California Walnut Commission has found a possible link between higher walnut consumption and increase in life expectancy among older US adults.

The article quotes the senior author:

What we’ve learned from this study is that even a few handfuls of walnuts per week may help promote longevity, especially among those whose diet quality isn’t great to begin with. It’s a practical tip that can be feasible for a number of people who are looking to improve their health, which is top of mind for many people.

Washington Post columnist Tamar Haspel tweeted about this study: “I have a pretty big beef with nutritional epidemiology, and there’s a new study on walnuts that pushes all my button[s].”

Her beefs:

  • Difficulties interpreting information from food frequency questionnaires
  • Complications of correcting for confounding variables (18 in this case)
  • Implications of causation (“lots of talk about the cardioprotective aspects of walnuts”)
  • The study was not pre-registered
  • It was funded by the walnut industry

Her view (with which I concur):

  • “Studies like the [sic] have helped create the mess that is nutrition advice”
  • “We DO NOT have the tools to assess the health impact of specific foods.”
  • “Eat a wide variety of whole-ish foods you enjoy in quantities consistent with the weight you want to be.  Eat walnuts if you like them.”

The study: Association of Walnut Consumption with Total and Cause-Specific Mortality and Life Expectancy in U.S. Adults.  Xiaoran Liu, Marta Guasch-Ferré, Deirdre K. Tobias, Yanping Li.

Method: Correlated information on dietary intake of walnuts from two large epidemiological studies  with mortality.

Conclusions: We reported that higher consumption of walnut was associated with a lower risk of all-cause mortality and CVD mortality in two large prospective studies of U.S. elder adults, especially among those with suboptimal dietary quality. We estimated a greater life expectancy at age 60 of 1.3 years in women and 1.26 years in men, among those who consumed walnuts more than 5 servings/week compared to non-consumers.

Conflicts of interest: Li has received research support from California Walnut Commission. The funder has no role in the design and conduct of the study, in the collection, analysis, and interpretation of the data, and in the preparation, review, or in the decision to publish the results. All other authors have reported that they have no relationships relevant to the contents of this paper to disclose.

Comment: In addition to Haspel’s comments, I would add that the statement that the funder had no role is difficult to evaluate.  Industry funders generally do not pay for research likely to come out with results unfavorable to their products and much evidence suggests that influence is exerted at an unconscious level.  I provide evidence for this and other observations about industry “funding effects”—observations that research sponsored by food companies almost invariably produces results favorable to the sponsor’s interests but that recipients of industry funding typically do not recognize its influence—in my book, Unsavory Truth: How Food Companies Skew the Science of What We Eat.

I must also point out that walnuts are not the only nuts singled out for specific health benefits.  See, for example, “Pecan-Enriched Diets Alter Cholesterol Profiles and Triglycerides in Adults at Risk for Cardiovascular Disease in a Randomized, Controlled Trial” in a recent issue of the Journal of Nutrition.  Its sponsor was the Georgia Pecan Commission.

The bottom line: eat whatever nuts you like.

Sep 6 2021

Industry-funded study of the week: full-fat dairy

The study: Impact of low-fat and full-fat dairy foods on fasting lipid profile and blood pressure: exploratory endpoints of a randomized controlled trial.  Kelsey A Schmidt, et al. The American Journal of Clinical Nutrition, nqab131, https://doi.org/10.1093/ajcn/nqab131.  Published: 13 July 2021

Background: “Dietary guidelines traditionally recommend low-fat dairy because dairy’s high saturated fat content is thought to promote cardiovascular disease (CVD). However, emerging evidence indicates that dairy fat may not negatively impact CVD risk factors when consumed in foods with a complex matrix.”

Method: “Participants were then randomly assigned to 1 of 3 diets, either continuing the limited-dairy diet or switching to a diet containing 3.3 servings/d of either low-fat or full-fat milk, yogurt, and cheese for 12 wk.”

Conclusions: “In men and women with metabolic syndrome, a diet rich in full-fat dairy had no effects on fasting lipid profile or blood pressure compared with diets limited in dairy or rich in low-fat dairy. Therefore, dairy fat, when consumed as part of complex whole foods, does not adversely impact these classic CVD risk factors.”

Funding: “National Dairy Council, Dairy Farmers of Canada, Dutch Dairy Association (Nederlandse Zuivel Organisatie), Dairy Australia, and the French Dairy Interbranch Organization (CNIEL),” and NIH and others.

Conflict of interest: “This study was initiated by the principal investigator (MK). The dairy-related funding organizations suggested changes to details of the study design prior to the conduct of the study, some of which were implemented. Otherwise, the funding organizations had no impact on the design or conduct of the trial or the analysis and interpretation of study data.”

Comment: Let’s give these investigators high marks for disclosing that the dairy funders influenced the design of the study, which, as we know from the data of Lisa Bero and her colleagues, is the place where biases caused by industry funding most typically show up.  Food companies that fund research are looking for benefits; they won’t risk study designs that might yield inconvenient results.

Reference: For a summary of research on the “funding effect”—the observations that research sponsored by food companies almost invariably produces results favorable to the sponsor’s interests and that recipients of industry funding typically did not intend to be influenced and do not recognize the influence—see my book, Unsavory Truth: How Food Companies Skew the Science of What We Eat.

Aug 23 2021

Industry-funded studies of the week: One Potato, Two Potato

One Potato

Thanks to David Ludwig for alerting me to an e-mail from the Alliance for Potato Research & Education (APRE), a trade association “dedicated to advancing the scientific understanding of the role potatoes play in promoting the health of all people.”

A new APRE-funded study published in Nutrients investigated the effect of increased dietary potassium from a whole food source – baked/boiled potatoes and baked French fries – or a potassium supplement on blood pressure and other cardiovascular disease risk factors compared to a ‘typical American’ control diet (lower potassium intake) among 30 pre-hypertensive-to-hypertensive men and women.

Results showed that baked/boiled potato consumption had the greatest benefit on reducing sodium retention, even more than the supplement, and resulted in a greater reduction in systolic blood pressure (SBP) compared to the control diet.

Further, despite commonly held misbeliefs about French fries and their role in heart-healthy lifestyles, the authors observed that a 330-calorie serving of baked French fries, when eaten as part of a ‘typical American’ diet, had no adverse effect on blood pressure or blood vessel function.

The study concludes:

This was the first controlled feeding study of potassium from food and supplements on BP and CVD outcomes in an unhealthy population…Of public health relevance is our observation that French fries in amounts typical of a large serving in a fast food restaurant has no adverse effect on blood pressure or endothelial function.

It discloses the funding source: “This research was funded by Alliance for Potato Research and Education.”

Comment: Because some (but not all) observational studies have linked potatoes, and especially French fries, to poor health outcomes, the potato industry wants research to give these foods a healthier image.  This study says that potatoes are high in potassium and a high potassium-to-sodium ratio is good for blood pressure and heart disease.  I could have told them that on the basis of food composition data alone: 100 grams of French fries contains 435 mg potassium versus 295 of sodium.  Does that make French fries a health food?  No, alas, it does not.

Once more for the record: industry-funded research is about marketing, not public health.

Two Potato

Last week, I received an emailed notification from APRE, the Alliance for Potato Research & Education announcing a new study.

For decades, people have often associated higher intakes of carbohydrate-containing foods with less healthy lifestyles. Yet, evidence suggests this view is overly simplistic, and it is instead the type and quality of carbohydrate foods that matter most for supporting health…In a newly published perspective in Nutrients, a group of nutrition researchers, who collectively make up the Quality Carbohydrate Coalition-Scientific Advisory Council (QCC-SAC), outline the opportunity for a stronger, more evidence-based approach to defining quality carbohydrate foods to support overall health and provide clearer dietary guidance.

The study: Toward an Evidence-Based Definition and Classification of Carbohydrate Food Quality: An Expert Panel Report.  Kevin B. Comerford, Yanni Papanikolaou,  Julie Miller Jones, Judith Rodriguez. Joanne Slavin,  Siddhartha Angadi.  and Adam Drewnowski.  Nutrients202113(8), 2667.

Conclusion: The identification of higher quality carbohydrate foods could improve evidence-based public health policies and programming—such as the 2025–2030 Dietary Guidelines for Americans. 

Funding:  This work was supported by the Quality Carbohydrate Coalition (QCC), which is funded by Potatoes USA. The QCC was not involved in the expert panel discussions, manuscript preparation, or the decision to submit the manuscript for publication.Conflicts of Interest: All authors are invited members of the Quality Carbohydrate Coalition’s Scientific Advisory Council (QCC-SAC). A.D. is the developer of the Nutrient Rich Food (NRF) index, a nutrient profiling model, and has received grants, contracts, and honoraria from entities, both public and private, with an interest in nutrient density of foods, complex meals, and the total diet. Y.P. is the president of Nutritional Strategies, collaborates on NHANES analyses and provides food, nutrition, and regulatory affairs consulting services for food/beverage companies and food-related associations. S.A. and J.M.J. advise the Grain Foods Foundation. J.S. has current grants from Taiyo and Barilla in the area of dietary fiber, and also serves on the Scientific Advisory Boards for Tate and Lyle and Atkins Nutritionals. J.R. has no conflicts of interest. K.B.C. is employed by FoodMinds, which provides science communications consulting services to various food and nutrition entities, including Potatoes USA and the Alliance for Potato Research and Education (APRE).
Comment: This is a successful effort by the potato industry to engage academics in support of the value of potatoes in healthful diets.  The role of potatoes in health is a contentious issue in the nutrition research community (see, for example, this FrontLine interview with Walter Willett).  The potato industry is fighting back by funding research (see above and also a previous post) and now engaging sympathetic academics.  I think potatoes are fine, in moderation.  But I wish academics would stay out of conflicted situations like this one.Reference: For a summary of research on the “funding effect”—the observations that research sponsored by food companies almost invariably produces results favorable to the sponsor’s interests and that recipients of industry funding typically did not intend to be influenced and do not recognize the influence—see my book, Unsavory Truth: How Food Companies Skew the Science of What We Eat.