Seems like it was only a few weeks ago that I was impelled to rebut the conclusions of an anti-meat study: “A bad study claims red meat is the culprit in dementia”
I’m getting tired of doing damage control on biased research by America’s diet minders, but here goes—let’s break it down.
The same Harvard study group is the source of the latest anti-butter agit-prop; previously I wrote:
“I always consider the source when looking at these types of studies. The Harvard T.H. Chan School of Public Health is renowned for espousing anti-meat, ‘planetary health’ goals. A large contributor is the Gates Foundation, which had taken significant equity positions in Beyond Meat, Impossible Foods, makers of vegan meat substitutes, and Upside Foods, a lab-grown meat company that grows meat from animal cells. Gates is on record as saying ‘I do think all rich countries should move to 100% synthetic beef.’”
Now, butter is in the crosshairs.
“Butter and Plant-Based Oils Intake and Mortality” is the latest salvo in the war against saturated fat. The study concludes (improbably) that:
“ . . . higher intake of butter was associated with increased mortality, while higher plant-based oils intake was associated with lower mortality. Substituting butter with plant-based oils may confer substantial benefits for preventing premature deaths.”
Before we address the glaring deficiencies of the study, let’s situate it within the current political environment, which unfortunately all-too-often shapes the direction science takes these days.
“RFK Jr. and Influencers Bash Seed Oils, Baffling Nutrition Scientists”heralds a headline in Medpage, an influential doctor website.
There’s already a pre-ordained conclusion among many orthodox nutrition scientists and medical professionals that RFK Jr. is a dangerous whack-job; once a darling of the progressive Left, he lost his cred with many in healthcare by aligning with Trump. His past anti-vaccine stances make him anathema to establishment medicine. According to Medpage:
“The seed oil discussion has exasperated nutrition scientists, who say decades of research confirms the health benefits of consuming such oils, especially in place of alternatives such as butter or lard. ‘I don’t know where it came from that seed oils are bad,” said Martha Belury, PhD, RD, an Ohio State University food science professor.’”
In a pointed critique (“Is seed oil better than butter? A new paper says YES, but is the paper any good?”) Dr. Vinay Prasad says the quiet part out loud:
“JAMA IM publishes anti-MAHA research, but is it good science or dirty politics? JAMA IM has a new clickbait study meant to criticize MAHA . . . This paper is not science; It is closer to propaganda. And given the political overtones it may be considered politically motivated or a form of campaigning . . . [It] is research misconduct.”
For the record, Prasad has been an outspoken critic of the shoddy science justifying draconian measures undertaken during the COVID pandemic—lockdowns, mandatory masking and compulsory vaccination.
The JAMA paper is a classic observational study, involving thousands of people (health professionals who may not be representative of the population as a whole) recording diet information based on a food frequency questionnaire (FFQ). Critics have assailed the FFQ:
“One prominent concern is the potential for measurement error in FFQs. These questionnaires rely on self-reported data from participants, which can introduce inaccuracies due to memory limitations and social desirability bias. Participants may not accurately recall their food consumption frequencies and portion sizes, leading to imprecise estimates of nutrient intake.
Recall bias is another critical issue in the reliability debate. Participants may selectively remember or misreport the consumption of certain foods or nutrients, leading to an overestimation or underestimation of actual dietary intake.”
In this case, butter use was assessed by calculating consumption of butter “from butter and margarine blend [!], spreadable butter added to food and bread, and butter used in baking and frying at home.”
Who eats butter straight? Butter is what you put on toast, bagels, croissants, rolls, waffles, pancakes, instant mashed potatoes and corn. Recipes for all manner of gooey desserts, cakes, cookies, muffins and noodle dishes call for entire sticks of butter!
Could it not be that butter consumption is simply a proxy for eating rich, carbohydrate-laden, caloric food in this study?
What constitutes “seed oils” for these researchers? Primarily olive oil, soybean oil, and canola. It’s an unforgivable methodological sin to lump olive oil—rich in monounsaturated fats and beneficial polyphenols—in with industrially-processed refined oils.
The authors claim an advantage was discernible even when olive oil was excluded from their analysis, but when other seed oils were evaluated—safflower, sunflower, corn oil—their “benefits” vanished. Unaddressed were effects associated with use of more esoteric plant oils—e.g. avocado, walnut, peanut, sesame, coconut, macadamia. One of the most highly-used seed oils, cotton seed oil—ubiquitous in chips, baked goods, fried fast foods and salad dressings—is nowhere in the analysis.
The claimed magnitude of the benefits of switching from butter to seed oils stretches credulity. Are we really to believe, as the authors assert, “Substituting 10-g/d intake [two teaspoons!] of total butter with an equivalent amount of total plant-based oils was associated with an estimated 17% reduction in total mortality and a 17% reduction in cancer mortality”? REALLY??
Undaunted, lead author Yu Zhang states, without irony: “What’s surprising is the magnitude of the association we found . . . That is a pretty huge effect on health.” Uh-huh.
Largely discounted by the researchers is that butter consumers may be fundamentally different from plant oil fans. In epidemiology, this rookie error is referred to as “confounding”. Adherents to one or another diet may be more or less affluent, educated, likely to smoke, drink or exercise, sicker or fatter. Bon vivants, heedless of risk, may gorge on butter (and maybe also don’t wear motorcycle helmets!); those substituting seed oils for butter, piously adhering to recommendations to reduce saturated fat consumption, may be health-conscious optimizers in general.
On that count they may be misguided. Several well-designed studies have exonerated butter as a health risk. A multi-country meta-analysispublished in 2016 in PLOS One concluded that:
“This systematic review and meta-analysis suggests relatively small or neutral overall associations of butter with mortality, CVD, and diabetes. These findings do not support a need for major emphasis in dietary guidelines on either increasing or decreasing butter consumption, in comparison to other better established dietary priorities.”
Nutritional epidemiology is messy; it’s not like studying the behavior of atomic particles in a cyclotron under carefully controlled conditions with exquisitely sensitive instrumentation. Peter Attia MD, popular host of The Drive podcast series writes:
“In spite of their many faults, observational studies in nutrition continue to be popular with the press, where spurious associations are often translated into flashy headlines. Moreover, food industry sponsorship has long ensured ample funding for nutrition studies, and on many occasions, this conflict of interest has been found to lead to flawed methodology or misleading reporting of results.”
And indeed the health establishment has a long, dark history of aligning with seed oils. It was revealed that, in the 1960s, the American Heart Association was paid off by Proctor and Gamble to say heart disease was caused by saturated fat, not seed oils and sugar. In the 1980s, multi-millionaire businessman Phil Sokolof went on an anti-saturated fat crusade, credited with forcing McDonald’s to end its practice of cooking their French fries in beef tallow, and substituting refined partially-hydrogenated vegetable oil, which is inherently less stable when subjected to repetitive high temperature cooking. Organizations like the Center for Science in the Public Interest applauded the move, publishing articles like “Saturated Fat Attack” to promulgate its message. To this day, the American Heart Association, reliant on corporate contributions, continues to recommend vegetable oil as a substitute for butter.
With all these flaws, it’s a miracle that this paper was accepted by a high-impact journal like JAMA, guaranteeing its amplification in the press. But backed by Harvard’s heft, and reinforcing the institutional party-line about the supposed evils of saturated fat and harms of livestock for planetary health, perhaps it’s no surprise. That it repudiates MAHA talking points about seed oils is an added bonus for medical journal ideologues.
That’s how too much research gets funded these days, in a self-perpetuating echo chamber; proceeding from an a priori narrative, applications are submitted and generous grants are awarded. Money pours in. Often, taxpayers are on the hook.
Poor quality studies like these don’t deter me from consuming moderate amounts of butter, but I draw the line at Julia Child-like exuberance. And, no, I don’t demonize seed oils like some lard zealots, but I do prioritize cold-pressed, unrefined versions in cooking, emphasize extra-virgin olive oil, and stay away from ultra-processed foods that are Trojan horses for industrially-processed oils.
For a more nuanced take on the seed oil controversy, see my recent article “7 ways to minimize the harms of cooking oils”
