Currently browsing posts about: Fruit

The California Table Grape Commission funds lots of research for an explicit purpose: “to help discover how and why grapes are beneficial to health.”

It lengthy list of funded projects is here.  Published studies are here.

You want to do one of these studies?  Let them know here.

Grape research is conducted using a freeze-dried table grape powder, designed to facilitate reproducible data and to provide researchers with a grape sample that is available year-round. Additionally, a grape powder placebo is made available.

Comment: If you want funding, you need to design your study to show benefits.  The Commission is unlikely to risk funding proposals unlikely to show benefits.  [Thanks to David Michaels for sending this one].

And Charles Platkin sent me the press release for one of the Commission’s funded studies: Hu, W., Zheng, R., Feng, Y., Tan, D., Chung-Tsing, G.C., Su, X., and Kim, J.E. (2023). Impacts of regular consumption of grapes on macular pigment accumulation in Singapore older adults: a randomized, controlled trial. Food Funct. 14, 8321-8330. Doi: 10.1039/d3fo02105j.  The abstract is here.

Conclusions: Regular intake of grapes may improve eye health in Singapore older adults, specifically in augmenting MPOD, which can be explained by an increase in plasma total antioxidant capacity and phenolic content, and the downregulation of AGEs.

I’m all for eating grapes and every other fruit.  Does one kind of fruit have more substantial effects on health than any other?  The study did not compare grapes to any other fruit; it just looked at the benefits of grapes.

I’m guessing lots of other fruits will do the same.

The moral: eat a variety of fruits and vegetables.  And be skeptical about the importance of studies like this.

Usually, I post something about research conflicts of intereest on Mondays, but am doing that today instead.

Three readers sent news about this study to me, so for that alone it’s worth sharing.

First, the press release:

Associations between mango eaters and moms-to-be: better diets and improved nutrient intakes: New NHANES analysis reveals meals including mangos associated with higher healthy eating index and better nutrition for healthy pregnancies.

Any time you see a headline like this, your first question should be: Who paid for this?

The study: Mango Consumption Was Associated with Higher Nutrient Intake and Diet Quality in Women of Childbearing Age and Older Adults.  Kristin Fulgoni and Victor L. Fulgoni III. Nutrients 2024, 16(2), 303; https://doi.org/10.3390/nu16020303.

Conclusion: “This study suggests incorporating mango into the diet could increase select nutrient intake as well as diet quality in specific life stages of adult Americans.”

Funding: “This research was funded by the National Mango Board.”  [Bingo!]

Conflicts of interest: V.L.F.III and K.F. are employees of Nutrition Impact, LLC, a food and nutrition consulting firm which analyses NHANES data for numerous food and beverage companies and related entities. Nutrition Impact has a contract with the National Mango Board.

Comment: The National Mango Board contracted with the authors to produce this analysis. Its results are predictable.  Guess what: eating fruit increases intake of the nutrients contained in that fruit.  Eating fruit increases the quality of the diet.  I could have told them that.

I do love mangos, although they taste much better—like eating perfume—in their countries of origin.  I’m allergic to their skins and pits, however, and have to eat them carefully.  The Mango Board must think research results like this will increase sales.

Here’s how the Mango Board advertises this fruit:

Mangos pack a nutritional punch.

• Each serving of mango is fat free, sodium free and cholesterol free.
• Mangos contain over 20 different vitamins and minerals, helping to make them a superfood.

I learned about this one from this article:  Prune consumption may prevent bone loss for postmenopausal women.  Dietary supplementation with prunes can have a broad range of effects on immune, inflammatory and oxidative stress markers in postmenopausal women, according to a recent study…. Read more

When I see a headline like this, my first question is , as always, who would pay for something like this?

I went right to the study:  De Souza MJ, Strock NCA, Williams NI, Lee H, Koltun KJ, Rogers C, Ferruzzi MG, Nakatsu CH, Weaver C. Prunes preserve hip bone mineral density in a 12-month randomized controlled trial in postmenopausal women: the Prune Study. Am J Clin Nutr. 2022 Oct 6;116(4):897-910. doi: 10.1093/ajcn/nqac189.

Conclusion: “The results of this investigation provide compelling evidence of the long-term efficacy of daily prune consumption.”

Funding: We thank the California Prune Board (Award Number: 180215) for the funding and prunes and the participants in this study.

Author disclosures: CW and CR are members of the Nutritional Advisory Panel for the California Prune Board. All other authors report no conflict of interest.

Comment: Bingo on this one.  Wouldn’t it be wonderful if all you had to do to prevent bone loss was to eat 5 prunes a day?   Go for it!

I’ve posted several studies sponsored by the blueberry industry , most recently on their effects on menopausal symptoms.  Blueberry trade associations, as I discuss in my book Unsavory Truth: How the Food Industry Skews the Science of What We Eat, led the way in promoting research suggesting this fruit is a “superfood.”

If only.

They are still at it, apparently, but sponsorship does not always guarantee the desired outcome.  Here is a rare exception to the rule that industry-sponsored studies almost invariably give results favorable to the sponsor’s marketing interest.  Let’s give credit where it is due.

• The study:  Chronic and postprandial effect of blueberries on cognitive function, alertness, and mood in participants with metabolic syndrome – results from a six-month, double-blind, randomized controlled trial.  The American Journal of Clinical Nutrition.  Available online 6 February 2024, https://doi.org/10.1016/j.ajcnut.2023.12.006
• Methods: “A double-blind, randomized controlled trial was conducted, assessing the primary effect of consuming freeze-dried blueberry powder, compared against an isocaloric placebo, on cardiometabolic health >6 mo and a 24 h postprandial period (at baseline).”
• Results: “Postprandial self-rated calmness significantly improved after 1 cup of blueberries (P = 0.01; q = 0.04; with an 11.6% improvement compared with baseline between 0 and 24 h for the 1 cup group), but all other mood, sleep, and cognitive function parameters were unaffected after postprandial and 6-mo blueberries.”
• Conclusion: “Although self-rated calmness improved postprandially, and significant cognition-metabolite associations were identified, our data did not support strong cognitive, mood, alertness, or sleep quality improvements in MetS participants after blueberry intervention.”
• Conflict of interest: “AC reports financial support provided by the US Highbush Blueberry Council (USHBC) and Biotechnology and Biological Sciences Research Council (BBSRC, UK). AC and EBR both act as advisors and consultants to the United States Highbush Blueberry Council grant committee. All other authors report no conflicts of interest.”
• Funding: “This work was supported by the United States Highbush Blueberry Council with oversight from the USDA and the Biotechnology and Biological Sciences Research Council (United Kingdom). The funders of this research had no involvement in this publication and have placed no restrictions on the publication of these data.”

Comment: In this instance, the last statement could well be correct (it isn’t always, alas).  I like blueberries but they are not a superfood.  There is no such thing as a superfood.  If you want to eat healthfully, by all means eat fruit—and enjoy the ones you like best.

I’m having a hard time with this one.

Once again, the FDA is warning all of us : “Do not eat, sell, or serve recalled cantaloupes or recalled products containing pre-cut cantaloupe.”

The warning lists the products implicated and all the ones that have been recalled.

The CDC says much the same:

CDC is concerned about this outbreak because the illnesses are severe and people in long-term care facilities and childcare centers have gotten sick. Do not eat pre-cut cantaloupes if you don’t know whether Malichita or Rudy brand cantaloupes were used.

As of November 30, the toll is:

Total Illnesses: 117
Hospitalizations: 61
Deaths: 2

But that’s only in the U.S.  Canada reports illnesses too: 63 sick, 17 hospitalized and 1 death.

This, mind you, is from eating cantaloupe.

It’s not that nobody knew cantaloupe poses special safety problems.  It’s grown on the ground and is hard to wash.  If it is grown anywhere near animal wastes, it has a high risk of getting Salmonella on its rind.  Cutting through the rind can move harmful bacteria on the rind into the interior.

Food safety lawyer Bill Marler, who tracks such things, reminds us of previous lawsuits over cantaloupe food poisonings.

He also has some useful things to say about Salmonella during a Cantaloupe Outbreak – Symptoms and Treatment

Cantaloupes, he points out, might still be in season, but Salmonella should not be.

He quotes Perdue (sic Purdue) Extension on how to make cantaloupe safer: scrub and wash in very hot water.

But Marler has been quoted as saying he does not eat cut fruit (implying you should not either).

What’s infuriating about all this is that Congress passed the Food Safety Modernization Act to give the FDA the power to require safety plans from producers of every food under its jurisdiction.  This means cantaloupe growers are supposed to take steps—and test—to make sure the fruit is not contaminated with pathogenic bacteria.

Clearly, the system isn’t working.

The FDA needs to find out why not.

The FDA is chronically and infamously underfunded for what it is supposed to do.

Congress needs to pay attention to this issue.

Nobody should get this sick from eating cut fruit.

And if you haven’t seen the film featuring Marler (I’m in it too, briefly), take a look at Poisoned on Netflix.  It talks about cantaloupe, among other things worth knowing.

I ran across a notice about this video: The USDA’s wondrous fruit watercolors.  It’s only 5 minutes and a revelation.

It’s just what we need this week—something lovely at a dark time.

I had never heard of the USDA’s collection of 7500 hand -illustrated fruits and vegetables, most of them contributed by women.

I’m happy to know about them.  The illustrations are available online at the National Agricultural Library.

You can search for images here.

They are in the public domain.

Overwhelmed as I am with an overabundance of Concord grapes this year, I searched for them.

They look good enough to eat, no?

This collection is a national treasure and I am thrilled to know about it.

I missed posting these last week (oops).

Blueberries set the standard for industry-funded studies (I discussed the origins of blueberry-industry funding in my book, Unsavory Truth).  Blueberry producers are still at it.  Here are two examples.

I.  This one started with a press release sent to my email:

From: Blueberries <updates@blueberrycouncil.org>
Date: August 29, 2023 at 11:59:59 AM EDT
Subject: Study Alert: New Research Links Blueberries to Gut Health Benefits

A new study published in Nutrients suggests blueberries may hold benefits for those suffering from functional gastrointestinal disorders (FGID). In this study, FGID patients saw greater abdominal symptom relief and improved markers of well-being, quality of life, and life functioning after consuming freeze-dried blueberry powder for 6 weeks as compared to a placebo treatment.

The study: Wilder-Smith CH, Materna A, Olesen SS. Blueberries Improve Abdominal Symptoms, Well-Being and Functioning in Patients with Functional Gastrointestinal Disorders. Nutrients. 2023; 15(10):2396. https://doi.org/10.3390/nu15102396.

Conclusion: Blueberries relieved abdominal symptoms and improved general markers of well-being, quality of life, and life functioning more than placebo in patients with FGID. Consequently, the polyphenol and fiber components of blueberries exert broad beneficial effects separate from the sugars present in both treatments.

Funding: This research was funded by a grant from the US Highbush Blueberry Council.

Comment: Of course it was.

II.  I read about this one in ConscienHealth.

Burning Fat with Wild Blueberries in 11 Athletes

This is nearly perfect clickbait that is just about meaningless for an average person in real life. Researchers did a study of fat oxidation after consuming freeze-dried powder from wild blueberries. They found an increased oxidation rate associated with consuming that powder in the 11 aerobically trained males they studied. So the press office at Cal Poly Humboldt, where the researchers work, issued a release saying wild blueberries help with burning fat.  From there, twitter and health reporters take the next leap, writing headlines like “eating wild blueberries can help you lose weight.”

The study: Pilolla KD, Armendariz J, Burrus BM, Baston DS, McCarthy KA, Bloedon TK. Effects of Wild Blueberries on Fat Oxidation Rates in Aerobically Trained Males. Nutrients. 2023; 15(6):1339. https://doi.org/10.3390/nu15061339.

Conclusion: “Results indicate that WBs may increase the rate of FAT-ox during moderate-intensity activity in healthy, active males.”

Funding: “This research was funded by Cal Poly Humboldt’s Dean of Research.* Freeze-dried Wild blueberry powder was donated by the Wild Blueberry Association of North America (WBANA).“

Comment: I agree that simply providing product to be tested is not an earth-shaking conflict of interest, but because the powder came from the WBANA the ties seem closer.  In any case, the idea that blueberry powder—not nearly as delicious as the real thing—can have these kinds of effects should raise eyebrows from the get go.  Studies of the health effects of one sincle food always require critical thinking and more than a modicum of skepticism.

As for the asterisk*:  My son went to Humboldt State College (long before it was taken over by Cal Poly) so I was especially interested in this.

I want to end the week with this unusual example.

Yes, avocados are fruits (hint: fruits have seeds).

This story begins with an emailed ad from an avocado trade association to subscribers to Today’s Dietitian.

In the largest study of its kind, published in the Journal of the American Heart Association, researchers across multiple institutions looked at the impact of consuming one avocado per day on weight-related measures, markers of cardiometabolic risk and diet quality—insights you won’t want to miss.

If you click around to further discussion, you get this:

Daily avocado consumption led to reductions in total and LDL cholesterol and improved diet quality compared to the control group. The Avocado Nutrition Center supported this study, and although the findings from one study cannot be generalized to larger populations, this study supports a growing body of evidence that suggests consuming heart-healthy avocados is associated with better diet quality.

Let’s take a look:

• The study: Effect of Incorporating 1 Avocado Per Day Versus Habitual Diet on Visceral Adiposity: A Randomized Trial. J Am Heart Assoc. . 2022 Jul 19;11(14):e025657.  doi: 10.1161/JAHA.122.025657. Epub 2022 Jul 5.  Authors: Alice H Lichtenstein ¹, Penny M Kris-Etherton ², Kristina S Petersen ³, Nirupa R Matthan ¹, Samuel Barnes ⁴, Mara Z Vitolins ⁵, Zhaoping Li ⁶, Joan Sabaté ⁷, Sujatha Rajaram ⁷, Shilpy Chowdhury ⁴, Kristin M Davis ⁸, Jean Galluccio ¹, Cheryl H Gilhooly ¹, Richard S Legro ⁹, Jason Li ⁶, Laura Lovato ¹⁰, Letitia H Perdue ¹⁰, Gayle Petty ¹, Anna M Rasmussen ⁶, Gina Segovia-Siapco ⁷, Rawiwan Sirirat ⁷, April Sun ⁶, David M Reboussin ¹⁰
• Conclusions: “In conclusion, in this randomized controlled multicenter parallel trial, the addition of 1 avocado per day to the habitual diet for 6 months in individuals with visceral adiposity did not reduce VAT and had minimal effect on risk factors associated with cardiometabolic disorders.”
• Funding: This work was supported by the Avocado Nutrition Center.

Comment: I don’t usually include the names of authors of industry-funded studies because I don’t see the “funding effect” (a higher probability of positive results) as personal to individual investigators; I see it as systematic.  But I listed these authors because they produced something quite rare: an industry-funded study that did not find positive results.  And they said so explicitly, without hedging or trying to spin the results so they looked  more favorable.

The avocado marketers did the spinning.  This, alas, is yet another hazard of  doing studies funded by food trade associations with vested interests in research outcome.  Investigators have no control over how the sponsor will use or spin their research results, as we see in this example.

Addition, September 16

I often hear criticisms that I don’t deal with the science when I post industry-funded studies.  I don’t because how the science is conducted is rarely the problem.  Instead, industry influence turns up most frequently in the study design or in the interpretation of the results.  That’s what’s happening here, as a reader, mrpicasso2, writes:

Wow! This is astounding how the Avocado marketers try to spin the results in their favor. “Changes in most secondary and additional outcome measures (cardiometabolic risk factors), except for modest decreases in total cholesterol and LDL‐C concentrations, were not statistically significant” became “Daily avocado consumption led to reductions in total and LDL cholesterol and improved diet quality compared to the control group.”

And even the “improved diet quality” is a big stretch because the Healthy Eating Index (HEI) values (even when split into below and above the median subgroups) were not significantly different. It’s true the avocado arm values were numerically higher (0.064 vs 0.044, and 0.083 vs 0.069) but without reaching statistical significance they are indistinguishable.

Of course the Avocado marketers don’t mention that there were 9 adverse events in the Avocado diet arm compared with none in the habitual diet group.

This reminds me of the story of the boy who was so excited to get a pile of horse manure for his birthday because he reasoned that with so much manure there had to be a pony near by.