Currently browsing posts about: Diets

Two previous short-term studies demonstrated that if you eat a diet based largely on ultra-processed foods, you are likely to consume far more calories than you would eating less processed diets–and not notice that you are overeating.

The big question: why.

Study #1:  Hall K, et al.  Ultra-Processed Diets Cause Excess Calorie Intake and Weight Gain: An Inpatient Randomized Controlled Trial of Ad Libitum Food Intake .  Cell Metabolism 2019; 30:67–77.

When study subjects ate the ultra-processed diet, they consumed 500 calories a day more than when they were eating the unprocessed diet.  This is a staggering difference.  They seemed to eat the ultra-processed diet faster.

Study #2: Hamano S, Sawada M, Aihara M, Sakurai Y, Sekine R, Usami S, Kubota N, Yamauchi T. Ultra-processed foods cause weight gain and increased energy intake associated with reduced chewing frequency: A randomized, open-label, crossover study. Diabetes Obes Metab. 2024 Nov;26(11):5431-5443. doi: 10.1111/dom.15922.

These investigators reported a difference of 813 calories.  They attributed it to less chewing.

Study #3 (as yet unpublished): Its results appeared as a Tweet (X) from Dr. Hall describing a presentation he gave at a meeting in London (Apparently, X is where science gets discussed these days).  The recording of the entire meeting is now available.  Dr Hall’s presentation begins at minute 38.

The latest result: a difference of 1000 calories a day!

Dr. Hall was kind enough to send me the slides from his presentation.

My translation:

• Blue bar: Minimally processed diet, low in energy density (calories per gram) and low in irresistably delicious (hyper-palatable) foods.
• Red bar: Ultra-processed diet high in energy density and high in hyper-palatable foods.

The big result: Difference between blue (unprocessed) and red (ultra-processed): 1000 calories a day.

• Purple bar: Ultra-processed high in energy density, low in hyper-palatable.
• Green bar: Ultra-processed low in energy density, low in hyper-palatable.

Difference between purple (high, low) and red: 200 calories a day.

Difference between green (low, low) and red: 630 calories a day.

Participants reported no differences in appetite or pleasantness of the meals on the various diets.  There also were no observable differences in eating rate.

Obviously, participants who ate more calories gained more weight.

Comment

My summary: We love and cannot stop eating yummy high-calorie foods.

All of this reminds me of the work of Barbara Rolls, who for years has argued for diets low in energy density, and whose low-energy-dense Volumetrics diet is consistently ranked at the top of diet plans.

It’s great to see all this research coming together.  Whatever the reasons—energy density, hyper-palatability, less chewing—the take-home-message seems utterly obvious: reduce intake of ultra-processed foods.

As Jerry Mande summarized the significance of this study, also in a Tweet (X) :

BREAKING..@KevinH_PhD  presents preliminary data from long awaited (6yrs!) follow-up study. Confirm initial findings. Energy dense, hyper-palatable UPF foods result in 1000 kcal/day greater intake than minimally processed food. Time to regulate UPF #MAHA

Indeed, yes.

Julian Baggini.  How the World Eats: A Global Food Philosophy. Granta, 2024.  443 pages.

I did a blurb for this one:

How the World Eats is an enormously wide overview of how people throughout the entire world–from hunter-gatherers to NASA astronauts–view, exist within, manage, and try to improve their food systems.  Baggini’s philosophy makes sense.  We need sustainable food systems to feed the world.

When I say “enormously wide,” I’m not kidding.  Baggini has interviewed an amazing number of people, including me.  I do not remember our interview (I don’t keep track of interviews), but he quotes me extensively—and my book Food Politics—especially in the chapter titled “The Big Business of Food.”

The book is long, not least because Baggini lets his interviews speak for themselves, regardless of their opinions on controversial food issues.  He does not use the book to argue with the people he interviewed.  If you want to know what everyone, everywhere thinks about food, from every side of an issue, this is a good starting place.

Eventually, Bagggini comes out in favor of food systems that are, in his words, “holistic, circular, pluralistic, foodcentric, resourceful, compassionate, and equitable.”

If we were to adopt the principles of Holism, Circularity, Pluralism, Foodcentrism, Resourcefulness, Compassion, and Equitability, many of the desiderata we have for the food world would come along for the ride. Everyone is in favour of sustainability, and that is what we would get if we followed these seven principles.  Similarly, a circular, plural and resourceful food system is also an efficient ne.  When the main things people want flow naturally from a set of principles, that is a good sign that those principles are the right ones.  p. 361

Two readers, Tara Kenny and Martin Caraher, sent this one:  Plant-based diets–impacts of consumption of little or no animal-source foods on human health.  by Alice V. Stanton  ^{Front. Nutr., 17 September 2024. Volume 11 – 2024 | https://doi.org/10.3389/fnut.2024.1423925}

The paper argues for the benefits of meat-based diets:

The protections provided by plant-based diets against NCDs [non-communicable diseases] appear to be more strongly associated with reduced intakes of calories and salt, and increased intakes of fruit, vegetables, nuts and whole grains, rather than with reduced intakes of ASFs [animal-source foods]. Any possible absolute adverse effects of red and processed meat consumption on NCDs are very small and uncertain…dietary guidelines should advise moderating excessive consumption, rather than substantially limiting or excluding ASFs from the human diet.

The author’s conflict-of-interest statement:

Alice Stanton was a part-time employee of Devenish Nutrition (2017–2023); and currently owns stock in Devenish Nutrition, an agri-technology company specializing in sustainable food solutions.

Comment

My readers point out that the author’s financial conflicts of interest are understated.  Devinish Nutrition is, in fact, a family business.  The company states it is “an innovator in animal nutrition by providing a wide range of products and services.”  It was acquired this year by EASY BIO a South Korean animal nutrition company.

Both readers also point out that Alice Stanton has pro-meat ideological conflicts of interest, but these concern me much less.  Everyone who does research has beliefs and hypotheses they want to test.  But not everyone stands to benefit financially from the outcome of their research or opinion, which is why full disclosure is so necessary.

Nina Guilbeault.  The Good Eater: A Vegan’s Search for the Future of Food.  Bloomsbury, 2024.

I did a back-cover blurb for this book:

The Good Eater is a vegan sociologist’s remarkably open-minded exploration of the historical, ethical, health, environmental, and social justice implications of not eating meat.  Guilbeault’s extensive research and interviews get right into the tough questions about this movement, leaving us free to choose for ourselves whether to eat this way.

Guilbeault has followed vegan dietary practices (no animal products) for a long time but was troubled by the self-righteousness and proselytizing of many vegans.  As a trained sociologist, she set out to investigate the origins, practices, and effects of vegan diets, through reading but also through interviews with what seems like everyone having anything to do with animal welfare and plant-forward diets.  The result is an exceptionally broad look at the who’s who of veganism, from historical figures to contemporary entrepreneurs and chefs.  The book is well written, rational, and not at all uncritical.

Here’s are a couple of excerpts:

Projections show that to avert environmental disaster by 2050 we need to reduce our meat consumption by at least a third, and by half in North America and Europe…But many people still eat eggs for breakfast and yogurt as a snack, put dairy milk in their coffee, add a slice of ham to their sandwich for lunch, and choose a piece of meat or fish for dinner, all in one day.  A reduction from that daily menu to a couple of eggs and a small piece of meat or fish once a week seems like a hefty drop, yet that is how humanity has eaten for most of our natural history.  (pp 284-285)

I can understand why, for many people, a vegan lifestyle seems unappealing, overwhelming, or even downright offensive.  As we know, meat has played a key part in our cultural and evolutionary history, and habits are notoriously difficult to break.  Veganism requires a shift in identity as well as the embrace of a social category still on the fringe….This is partly because being vegan in a non-vegan world is hard, but also because the vegan movement places an emphasis on moral perfection.  Yet…long-lasting, sustainable change doesn’t come from a place of shame, judgment, and guilt.  It comes from a place of joy and a sense of belonging.  (p 290)

 

Conclusions and Relevance  In this randomized clinical trial, we observed cardiometabolic advantages for the healthy vegan vs the healthy omnivorous diet among healthy, adult identical twins. Clinicians may consider recommending plant-based diets to reduce cardiometabolic risk factors, as well as aligning with environmental benefits.

The study has its share of detractors, American Council on Science and Health (ACSH), for example: Stanford Medicine Releases Confirmation Bias Study; Media Takes The Bait.  Its chief criticisms

• The improvements were in biomarkers, not health.
• Both diets were healthy,
• Obviously, diets without cholesterol will reduce cholesterol.
• Vitamin B12 levels were ldeficient on the vegan diet.

Comment: The ACSH is an industry-funded front group.  Low B12 is an easy problem to solve, and vegans, who by definition eat no foods of animal origin, have to make sure they complensate for its absence.

The twin idea is clever and adorable—and the reason for the press attention and for the Netflix documentary.  The study shows that vegan diets improve cardiovascular risk biomarkers in healthy people.  Why not?  This is further evidence for the benefits of largely plant-based diets.

Several readers wrote suggesting I take a look at the conflicts of interest statement on this paper.

It comes from the Harvard TH Chan School of Public Health, which issued a press release: Harvard study: ‘Portfolio diet’ may decrease risk of heart disease, stroke.

The portfolio diet—a plant-based diet designed to lower unhealthy cholesterol, emphasizing plant proteins (legumes), phytosterols (nuts and seeds), viscous fiber (oats, barley, berries, apples), and plant-based monounsaturated fatty acids (avocado)—may lower the risk of heart disease and stroke, according to a new study co-authored by researchers at Harvard T.H. Chan School of Public Health.

The study was published in Circulation, which also sent out a press release: Ever heard of the portfolio diet? It may lower risk for heart disease and stroke.

The study itself, Portfolio Diet Score and Risk of Cardiovascular Disease: Findings From 3 Prospective Cohort Studies, produced results that should be expected from eating healthier diets.

Background: The plant-based Portfolio dietary pattern includes recognized cholesterol-lowering foods (ie, plant protein, nuts, viscous fiber, phytosterols, and plant monounsaturated fats) shown to improve several cardiovascular disease (CVD) risk factors in randomized controlled trials.

Objective: to examine the relationship between the Portfolio Diet Score (PDS) and the risk of total CVD, coronary heart disease (CHD), and stroke.

Methods: We prospectively followed 73924 women in the Nurses’ Health Study (1984–2016), 92346 women in the Nurses’ Health Study II (1991–2017), and 43970 men in the Health Professionals Follow-up Study (1986–2016) without CVD or cancer at baseline. Diet was assessed using validated food frequency questionnaires at baseline and every 4 years using a PDS that positively ranks plant protein (legumes), nuts and seeds, viscous fiber sources, phytosterols (mg/day), and plant monounsaturated fat sources, and negatively ranks foods high in saturated fat and cholesterol.

Conclusions: The PDS was associated with a lower risk of CVD, including CHD and stroke, and a more favorable blood lipid and inflammatory profile, in 3 large prospective cohorts.

This report was funded by Canadian and U.S. government research agencies.

Comment: The reason readers sent this to me had to do with the authors’ reported conflicts of interest.  These take up the equivalent of an entire page in the journal and refer to a curious mixture of financial support or connections, paid and unpaid, with government agencies and foundations, authors’ and sometimes their spouses’—in addition to long lists of financial ties to food trade associations for one or another plant food included in the Portfolio diet.

Muddying up disclosure statements like this is inappropriate.  Many connections listed do not in any way imply conflicted interests.  Mixing them up with those that do takes the focus away from financial ties that could have influenced the design or interpretation of the study.

Financial connections to food companies raise questions of credibility in nutrition research.  At the very least, they give the appearance of industry influence.

Disclosure lists like these either reflect ignorance of the significance and harm causes by conflicts of interest or deliberate disdain for its meanings.  If Circulation is requiring this mix of disclosures, it should reevaluate its policy.

Just because these disclosures come in a study from Harvard does not make them OK.

The Government Accountability Office has produced a “snapshot” on Healthy Eating: Government-wide solutions for promoting healthy diets, food safety, and food security.  It’s only two pages; take a look.

As of July 2022, many of our recommendations for developing strategies on healthy eating have not yet been addressed.

1. Strategy Needed to Address Diet-Related Chronic Health Conditions
Three diet-related chronic health conditions (cardiovascular diseases, diabetes, and cancer) were among the 10 leading causes of death in 2018, according to CDC. Men, Black or African Americans, and people living in southern states had disproportionately higher mortality rates from diet related conditions. Dietary changes could have prevented some of these deaths.

Additionally, in 2018, about three in four adults in the U.S. had excess weight, which can be associated with poor diet and lead to cardiovascular diseases, diabetes, and cancer.

The GAO recommends that the federal government establish leadership for strategies:

• On diet-related efforts
• Food-safety oversight
• Nutrition assistance programs to respond to emergencies

Excellent suggestions.  If only they could be implemented.

Here are three announcements I received this week.

I.  Pringles shoots for spider history.  The Kidney Garden Spider bears an uncanny resemblance to the Pringles logo – sparking a mission to get the arachnid community to officially recognise it as the Pringles Spider…. Read more

II.  Milk cows listening to music are more relaxed.  Musical enrichment of the environment was done using recorded-tape of flute and sitar was played in yamen raga at 40-60 (dB) decibel intensity.   [Thanks to Stephan van Vliet for this one].

III.  Dating for diet followers: The Filteroff dating app is hosting an online speed dating event for followers of the Paleo and Keto diets.  You can learn more about the speed dating event (and sign up if single) here.  [Thanks to Michelle Miller of Filteroff for the emailed invitation].