Archive for the “Bad Science” Category
Well, I guess fans of the Atlanta Falcons are stuffing themselves with saturated fat today. Meanwhile, fans of the New England Patriots – who saw their team stage the greatest comeback in Super Bowl history – are probably cutting back on saturated fat and possibly losing a few pounds by eating less overall.
I know this because of a study I stumbled across in my database. Here are some quotes from an NPR online article about the study:
Backing a losing NFL team isn’t just bad for your pride. It’s bad for your waistline.
A study that links sports outcomes with the eating behavior of fans finds that backers of NFL teams eat more food and fattier food the day after a loss. Backers of winning teams, by contrast, eat lighter food, and in moderation.
Dangit. Since Atlanta is in Georgia, this is going to add fuel to that whole “southerners are fatter than northerners” myth. It is a myth, by the way. As I explained in a previous post, the belief that southerners are fatter is the result of those danged Yankees lying about their weight in phone surveys. But back to the NPR article:
After a defeat, the researchers found that saturated fat consumption went up by 16 percent, while after a victory it decreased by 9 percent. “After a victory, people eat better,” says Pierre Chandon, a professor of marketing at the business school INSEAD in France. “After a defeat, people eat a lot worse.”
In many ways, the research fits with what we already know about the psychology of eating. When many of us feel miserable, we’ll down a big bag of candy. Call it a form of self-medication – when your happiness levels are low, junk food and high-calorie food provide the brain with much-needed pleasure.
Wait a minute … something here doesn’t quite make sense. Let’s put toggle back and forth between two of those sentences:
Backers of NFL teams eat more food and fattier food the day after a loss.
When many of us feel miserable, we’ll down a big bag of candy.
Backers of NFL teams eat more food and fattier food the day after a loss.
When many of us feel miserable, we’ll down a big bag of candy.
I could’ve sworn people eat candy for the sugar, not the saturated fat. And yet the study seems to be saying people comfort themselves after their NFL team loses by eating more saturated fat. Let’s read on.
Chandon and his co-author Yann Cornil, also at INSEAD, find the same thing happening with sports defeats. They tracked the eating behavior of people in cities with NFL teams and measured how eating changed after victories and defeats.
Chandon says the connection between eating and sports outcomes was off the charts in the cities where following the local football team was tantamount to a religion.
“When we look at the behavior of people living in cities where football is really important — places like Green Bay, Philadelphia or Pittsburgh, then the performance of the team has an even greater impact on what they eat,” Chandon says.
After a loss, people in those cities eat 28 percent more saturated fat. A win swayed them over to eat 16 percent less saturated fat. “So, in those cities, people are even more responsive to the wining or the losing of the football team,” says Chandon.
Maybe that’s why the people in San Diego didn’t vote to build the Chargers a new stadium. Given the team’s lousy record in recent years, perhaps voters figured they’d eat less if the Chargers did their losing somewhere else.
In one part of their study, the researchers found that asking people to remember terrible sports defeats had even bigger effects on what they ate – defeats lead to a 45 percent increase in saturated fat consumption.
Well then, for heavenssakes, don’t ever talk to me about the 1984 Cubs, the 1989 Cubs or the 2003 Cubs. I might go crazy on saturated fat.
The most interesting part of Chandon’s research might not be the effects of defeats, but the effect that victories seem to have on fans. Winning seems to make people think long-term – they look forward to the next match, for example. The satisfaction of winning increases the capacity of people to withstand difficult choices – to pick the salad over the fries.
Now that you mention it, I finally began to truly appreciate the taste of lettuce right after the last play of the 2016 World Series. I just didn’t make the connection.
But I still don’t see why the researchers focused so much on saturated fat. So I took a peek at the study. Here’s the relevant portion:
We examined two measures of unhealthy eating: saturated-fat consumption and total food-based caloric consumption, both of which are major contributors to cardiovascular diseases and obesity (Hu et al., 1997). Unlike other macronutrients, which are present in all kinds of foods, saturated fats are present mostly in highly processed, calorie-rich, nutrient-poor “junk” food (e.g., pizza, cakes and cookies, dairy-based desserts).
Well, there you have it. Unlike the other macronutrients (which would be protein and carbohydrates), saturated fat is present mostly in highly processed junk foods, according to the study authors.
The only things wrong with that statement are 1) saturated fat isn’t a macronutrient (fat is), 2) saturated fats are present in all kinds of unprocessed and natural foods (meats, eggs, whole milk, yogurt, cheeses), and 3) carbohydrates are most definitely present in countless processed junk foods … including pizza, cakes and cookies, dairy-based desserts.
In fact, I’m going to step out a limb here and say that when people eat comfort foods like pizza, cakes and cookies, dairy-based desserts, etc., it’s because they want the sugar and flour. After all, plenty of cakes and cookies these days are made with vegetable oils. And as the article said, When many of us feel miserable, we’ll down a big bag of candy.
So the researchers made the usual guilt-by-association mistake: they see people stuffing themselves with foods that contain saturated fat and sugar, or saturated fat and white flour, or saturated fat and sugar and white flour, and assume the problem is the saturated fat – because the stuff is so unhealthy, ya know. Dr. Hu at Harvard said so, which means it must be true.
Chandon says he had seen the effects of the research firsthand. The same thing applies to soccer, he explains: “As a Frenchman, both the performance and the behavior of the French soccer team were so distressing, I’m sure it’s part of the reason why I gained so much weight lately.”
Let me offer some advice, Professor Chandon: the next time the French soccer team loses, skip the pizza, cakes and cookies, diary-based desserts, etc., and just eat more bacon. I promise you won’t gain any weight.
52 Comments »
Follow the money. Follow the money. Follow the money.
If you’ve seen Fat Head, you probably remember that line. Here’s a perfect example of why you should follow the money, as reported in The New York Times:
The sugar industry paid scientists in the 1960s to play down the link between sugar and heart disease and promote saturated fat as the culprit instead, newly released historical documents show.
Shocking, isn’t it? Actually, no, it’s not shocking. Arterycloggingsaturatedfat! hysteria was always about money.
The internal sugar industry documents, recently discovered by a researcher at the University of California, San Francisco, and published Monday in JAMA Internal Medicine, suggest that five decades of research into the role of nutrition and heart disease, including many of today’s dietary recommendations, may have been largely shaped by the sugar industry.
The documents show that a trade group called the Sugar Research Foundation, known today as the Sugar Association, paid three Harvard scientists the equivalent of about $50,000 in today’s dollars to publish a 1967 review of research on sugar, fat and heart disease. The studies used in the review were handpicked by the sugar group, and the article, which was published in the prestigious New England Journal of Medicine, minimized the link between sugar and heart health and cast aspersions on the role of saturated fat.
The Harvard scientists were not only whores, they were cheap whores. The equivalent of $50,000 in today’s dollars to steer the blame for heart disease from sugar to fat? Man, you got taken. Think of all those Snackwell’s sold in the ‘80s – fat-free, so they’re guilt-free! Think of all the sugary products (Cocoa Puffs come to mind) that sported the American Heart Association seal of approval because they were low in fat. You morons should have demanded at least $10 million each.
The Harvard scientists and the sugar executives with whom they collaborated are no longer alive.
Funny how always seems to be the case, isn’t it? We learn about these scientific shenanigans after the shenanigators are deceased. Back in April, I wrote about a “rediscovered” study conducted in the 1960s in which subjects who cut back on animal fats in favor of vegetable oils actually had a higher rate of heart disease. The investigators apparently buried the study. One of those investigators was Ancel Keys – long deceased when the data was “rediscovered.”
One of the scientists who was paid by the sugar industry was D. Mark Hegsted, who went on to become the head of nutrition at the United States Department of Agriculture, where in 1977 he helped draft the forerunner to the federal government’s dietary guidelines. Another scientist was Dr. Fredrick J. Stare, the chairman of Harvard’s nutrition department.
If you’ve read Good Calories, Bad Calories or The Big Fat Surprise, you know how much influence these two shenanigators had on our diets over the decades.
Dr. Hegsted used his research to influence the government’s dietary recommendations, which emphasized saturated fat as a driver of heart disease while largely characterizing sugar as empty calories linked to tooth decay. Today, the saturated fat warnings remain a cornerstone of the government’s dietary guidelines, though in recent years the American Heart Association, the World Health Organization and other health authorities have also begun to warn that too much added sugar may increase cardiovascular disease risk.
Way to go, American Heart Association! It only took you 40 years to become sort of half-right about diets and health! If I live to be 120 or so, I might even see you drop the nonsense about arterycloggingsaturatedfat!
The documents show that in 1964, John Hickson, a top sugar industry executive, discussed a plan with others in the industry to shift public opinion “through our research and information and legislative programs.”
At the time, studies had begun pointing to a relationship between high-sugar diets and the country’s high rates of heart disease. At the same time, other scientists, including the prominent Minnesota physiologist Ancel Keys, were investigating a competing theory that it was saturated fat and dietary cholesterol that posed the biggest risk for heart disease.
In 1965, Mr. Hickson enlisted the Harvard researchers to write a review that would debunk the anti-sugar studies. He paid them a total of $6,500, the equivalent of $49,000 today. Mr. Hickson selected the papers for them to review and made it clear he wanted the result to favor sugar.
Harvard’s Dr. Hegsted reassured the sugar executives. “We are well aware of your particular interest,” he wrote, “and will cover this as well as we can.”
I’m pretty sure as well as we can didn’t mean as objectively as we can.
As they worked on their review, the Harvard researchers shared and discussed early drafts with Mr. Hickson, who responded that he was pleased with what they were writing.
“Good job, guys. If you meet me in the underground parking garage around midnight tomorrow, I’ll give you thick envelope full of other scientific insights I’d like to share, mostly in the form of unmarked bills.”
Dr. Walter Willett, chairman of the nutrition department at the Harvard T. H. Chan School of Public Health, said that academic conflict-of-interest rules had changed significantly since the 1960s, but that the industry papers were a reminder of “why research should be supported by public funding rather than depending on industry funding.”
Awww, isn’t that cute? Dr. Willet thinks research supported by “public funding” is unbiased. I mean, it’s not as if “public funding” was yanked away from researchers who disagreed with the Lipid Hypothesis once the U.S. government bought into the idea. And it’s not as if studies supported by “public funding” were buried when the results weren’t what the overlords at the USDA and NIH wanted to hear.
The fact of the matter is that is there is no easy answer for the funding problem. Industries will of course support researchers who produce results the industries like. But governments do exactly the same thing. All we can do is try to become scientifically literate enough to separate the garbage studies from the legitimate studies – some of which are funded by governments, and some of which are funded by industries.
After the review was published, the debate about sugar and heart disease died down, while low-fat diets gained the endorsement of many health authorities.
Welcome to Snackwell’s, Slim-Fast, fat-free frozen yogurt, cereal instead of eggs for breakfast, Weight Watchers Smart Ones frozen dinners, I Can’t Believe It’s Not Butter, chocolate-flavored skim milk in schools, and countless sugar-and-grain products proudly bearing the American Heart Association’s seal of approval – oh, and the diabetes epidemic too.
I hope those jackasses really enjoyed the $49,000.
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Australian celebrity chef Pete Evans (who visited the Fat Head farm in 2015) sent me a link to an article warning diabetics away from the paleo diet. Let’s take a look:
People with type 2 diabetes should ditch the paleo diet until there’s substantial clinical evidence supporting its health benefits, warns the head of the Australian Diabetes Society.
It may be popular among celebrities but there’s little evidence to support the dozens of claims it can help manage the disease, says Associate Professor Sof Andrikopoulos.
Andrikopoulos isn’t exactly a common name, yet it sounded familiar. So I searched the blog. Sure enough, I wrote a post about the Aussie perfesser back in February after he produced a study purporting to demonstrate that a paleo diet will makes us fat and sick. I say purporting because the (ahem) “study” was on mice … and the “paleo” diet tripled the furry little subjects’ sugar intake, provided all their protein in the form of casein (just like yer average paleo diet, eh?) and increased their normal fat intake by 2567 percent – with much of the fat coming from canola oil. Yup, sounds exactly like my paleo diet.
After reading about that (ahem) “study,” I concluded that perfesser Andrikopoulos is an intelligent imbecile. The article Pete Evans forwarded didn’t dissuade me from that conclusion:
“There have been only two trials worldwide of people with type 2 diabetes on what looks to be a paleo diet,” he [Andrikopoulos ] said. “Both studies had fewer than 20 participants, one had no control diet, and at 12 weeks or less, neither study lasted long enough for us to draw solid conclusions about the impact on weight or glycemic control.”
And here I thought the fact that millions of people around the world lived on paleo diets for hundreds of centuries counted as a test. I seem to recall that doctors who examined hunter-gatherer tribes in modern times found almost no evidence of obesity, cancer, diabetes or heart disease.
The controversial paleo diet, followed by many high profile people including celebrity chef Pete Evans, advocates a high consumption of meat and cuts out whole grains and dairy, which is problematic because it may forgo important sources of fibre and calcium, says Andrikopoulos.
That would explain why paleo humans had such weak bones and went extinct thousands of years ago.
“And high-fat, zero-carb diets promoted by some celebrities make this worse, as they can lead to rapid weight gain, as well as increase your risk of heart disease,” he said.
I see. So the perfesser believes:
1) There have only been two trials testing a paleo-type diet
2) Those trials aren’t relevant because they had fewer than 20 participants and lasted 12 weeks
3) LCHF diets lead to rapid weight gain
4) LCHF diets increase your risk of heart disease
Gee, if only we lived in an age where people could easily find information on published studies. Oh, wait – we do. So let me spend … oh, I don’t know, maybe 90 seconds .. searching my database of studies and see what I can find.
This study compared the effects of a low-carb vs. low-fat diet for a full year. (The perfesser may not know this, but a year is way longer than 12 weeks. It’s like, uh, 52 weeks or something.) Here are the results and conclusions:
Participants on the low-carbohydrate diet had greater decreases in weight, fat mass, ratio of total-high-density lipoprotein (HDL) cholesterol, and triglyceride level and greater increases in HDL cholesterol level than those on the low-fat diet.
The low-carbohydrate diet was more effective for weight loss and cardiovascular risk factor reduction than the low-fat diet. Restricting carbohydrate may be an option for persons seeking to lose weight and reduce cardiovascular risk factors.
I’m no perfesser, but I’m pretty sure more effective for weight loss and cardiovascular risk factor reduction is the exact opposite of rapid weight gain and increase your risk of heart disease.
This study of a low-carb vs. low-fat diet lasted 24 weeks, which, if my math skills haven’t slipped, is less than a year but still way more than 12 weeks. Here are the results and conclusions:
LC achieved greater reductions in triglycerides and glucose variance indices. LC induced greater HbA1c reductions and HDL cholesterol increases in participants.
This suggests an LC diet with low saturated fat may be an effective dietary approach for T2DM management if effects are sustained beyond 24 weeks.
Lower triglycerides and lower A1c (average blood glucose) on low-carb. Yes, I can see why the head of Diabetes Australia would be against such a wacky, untested diet.
Which leads us to wonder what the perfesser does believe. Well, we know he’s a stickler for good, solid science because of this quote:
“Both studies had fewer than 20 participants, one had no control diet, and at 12 weeks or less, neither study lasted long enough for us to draw solid conclusions about the impact on weight or glycemic control.”
Okay, then. We mustn’t draw conclusions from studies with fewer than 20 participants that only last 12 weeks. Got it, perfesser. Way to stand up for solid science.
Uh, but wait … let’s go back to that study of the “paleo” diet I wrote about back in February. The subjects were mice – just 17 of them. And the study lasted just eight weeks. Not exactly up to the perfesser’s standards, at least when he wants to diss studies of paleo diets. And yet, he touted his mouse (ahem) “study” as evidence that the paleo diet will make us fat and sick. (Assuming, of course, that a paleo diet triples sugar intake, wildly increases fat intake, and limits protein to a dairy product. And that the people consuming it are mice.)
Well, maybe we just caught the perfesser on a bad day. Let’s see what other research he has out there. Here are some quotes from another recent article titled How sugar with a burger could be healthier:
Forget just the fries with that— weight watchers may be better off sipping a sugary drink with their burger to protect against weight gain.
A shocking new finding in a Victorian study shows a burger and chips with coke appears to be better for us than opting for a water, juice or diet soft drink.
Better for us? So they must have measured health outcomes over a long period, eh? I’m sure perfesser Andrikopoulos would insist on such rigorous standards before reaching a conclusion.
In a trial, Austin Health fed participants burgers and different drinks combinations to see what effect it had on their health.
They found that those that had coke instead of a healthy drink with their meal were more likely to feel fuller for longer and perhaps stop them from over-eating later on.
The coke-drinkers reported feeling fuller, apparently after a test with exactly one meal … and from this, we make the leap to “perhaps stop them over-eating later on” … and then the leap to “chips with coke appears to be better for us.” Well, heck yes, that makes perfect scientific sense.
Dr Sof Andrikopoulos, Associate Professor of medicine at the University of Melbourne at Austin Health, said they thought that feeding mice meals that were high fat and sugar would lead to weight gain.
“In actual fact what we found what was the opposite,” Dr Andrikopoulos said.
“If we had animals on the fructose diet they gained weight, if we had them on the high fat diet they also gained weight, but if we combined the two fructose and the high fat diet together, they were prevented from gaining weight.”
Dr Andrikopoulos said if you have a fatty meal, it is probably worth having a fructose drink to make you feel full longer afterwards.
Because that’s what the stickler-for-rigorous-science perfesser saw in a one-meal study of “fullness” on humans, plus a very short study with mice … which means humans should probably have a sugary drink when eating a fatty meal. Great. I mean, it’s not like fat mixed with sugar is the worst possible combination or anything.
So to sum up:
Perfesser Andrikopoulos believes a low-carb paleo diet will make people fat and sick. He also believes that a sugary drink helps people feel fuller and might prevent them from overeating, thus leading to better health.
This is coming from the head of the Australian Diabetes Society. I believe that helps explain an ongoing tragedy reported by ABC News in Australia:
In the past year alone we’ve seen another 100,000 Australians diagnosed with diabetes.
But gosh no, don’t listen to Pete Evans. Listen to the (ahem) “experts.” They’ve done such a good job so far — and they’re such champions of solid, consistent science.
71 Comments »
The most recent Dietary Guidelines declared that cholesterol is “no longer a nutrient of concern.” Yup, after nearly 40 years of warning people away from egg yolks, the government folks finally checked the actual science and then sort of admitted being wrong. It was a step forward. But, government being what it is, I suppose a corresponding step backwards was inevitable. Here are some quotes from a recent article in The Chicago Tribune:
The Obama administration is pressuring the food industry to make foods from breads to sliced turkey less salty, proposing long-awaited sodium guidelines in an effort to prevent thousands of deaths each year from heart disease and stroke.
So the Obama administration must have solid scientific evidence that reducing sodium in food products will prevent heart attacks and strokes … just like the First Lady must have solid evidence that telling kids “Let’s Move!” and cutting the fat and calories in their school lunches will reduce obesity. But we’ll come back to the salt-cardiovascular disease evidence.
The guidelines released Wednesday by the Food and Drug Administration are voluntary, so food companies won’t be required to comply, and it could be a year or more before they are final. But the idea is to persuade companies and restaurants — many of which have already lowered sodium levels in their products — to take a more consistent approach.
Ah, I see: the guidelines are voluntary. Based on government history, here’s how that will work:
“Hey, food companies, we’d like you volunteer to reduce the sodium in food.”
“No thanks. People don’t like the food as much when we lower the sodium.”
“You don’t seem to understand. We’re asking you to do this voluntarily.”
“Got it. Voluntary guidelines. So we choose not to follow them.”
“Well, then, we’ll have to force you to follow them.”
“But you said the guidelines were voluntary.”
“Yes, but you didn’t volunteer, so now we’re imposing them.”
Sodium content already is included on existing food labels, but the government has not set specific sodium recommendations. The guidelines suggest limits for about 150 categories of foods, from cereals to pizzas and sandwiches. There are two-year and 10-year goals.
And a five-year plan issued by the Kremlin.
Health officials from the FDA and the Centers for Disease Control and Prevention said overwhelming scientific evidence shows that blood pressure increases when sodium intake increases, increasing the chances of heart disease and stroke.
Overwhelming evidence, eh? That would mean 1) the science shows that high sodium intake leads to heart attacks and strokes, and 2) the science also shows that most Americans have a high sodium intake that puts them at risk. And let’s add a third point: before issuing a “voluntary” guideline for lowering the sodium in food, we’d want to be sure that people don’t respond to low-sodium foods by reaching for the salt shaker – which is what I do.
So how much sodium are we consuming, anyway?
Americans eat about 1½ teaspoons of salt daily, or 3,400 milligrams. That amount hasn’t gone down over the years, and it’s about a third more than the government recommends for good health. Most of that sodium is hidden inside common processed foods and restaurant meals, making it harder for consumers to control how much they eat.
I just explained that I have no trouble controlling how much sodium I eat. Give me low-sodium food, I reach for the salt shaker. That’s because 1) I like salt on my food, and 2) I’ve actually looked at the science – something regulators at the FDA apparently haven’t. Here’s a quote from a 2011 article in Scientific American:
A meta-analysis of seven studies involving a total of 6,250 subjects in the American Journal of Hypertension found no strong evidence that cutting salt intake reduces the risk for heart attacks, strokes or death in people with normal or high blood pressure.
And here are some quotes from a recent article about a new meta-analysis:
A controversial new study contends that a low-salt diet could be dangerous for your heart health.
Notice how it’s only “controversial” if a study concludes that government advice is wrong?
Restricting dietary salt to below 3,000 milligrams a day appears to increase the risk for heart disease similar to that of high blood pressure patients who eat too much salt, said lead researcher Andrew Mente.
He said his study results showed that a low-salt diet increases the risk of heart attack or stroke 26 percent for people without high blood pressure and 34 percent for people with high blood pressure.
For those with high blood pressure, too much dietary salt increases their risk 23 percent, the study said.
On the other hand, a diet with excess salt doesn’t increase the risk at all if blood pressure is normal, the study reported.
“Most of the population eats what they’re supposed to eat, based on the data,” Mente said. “They fall in the middle and that’s actually the sweet spot — the safest range of intake.”
Mente’s study is observational, and you know what I think of observational studies are far as demonstrating cause and effect. But keep in mind that if A causes B, A and B will be correlated. So if A isn’t correlated with B, A doesn’t cause B. Mente found that a normal sodium intake – the 3400 milligrams the government says is too much – isn’t associated with heart attacks of strokes. But a lower sodium intake is. So naturally, the FDA wants us to cut back. And they’re (ahem) “asking” food companies to volunteer to help.
Back to the Tribune article:
Some companies have worried that though the limits will be voluntary, the FDA is at heart a regulatory agency, and the guidelines are more warning than suggestion.
Gee, do you think?
51 Comments »
Suppose you were an idiot. And suppose you were a nutrition scientist. But I repeat myself.
Sorry, just couldn’t resist borrowing from Mark Twain. Let me try again.
Suppose you’re a nutrition scientist. And suppose you conduct a study, all the while expecting the results to support a hypothesis you already believe. But then — @#$%!! — the results undermine the hypothesis.
Oh, dear, what to do?
We saw one way to handle that sticky situation in our last episode: just don’t publish the results. Ancel Keys conducted a clinical study in which people who consumed vegetable oils instead of arterycloggingsaturatedfats!! had higher mortality rates – including higher mortality from heart disease. Keys didn’t like that result, so the data gathered dust for 40 years. Nice move, Ancel.
Here’s another way to handle results you don’t like: explain them away. I found a couple examples of that method while looking through my database of studies recently.
In one study, researchers looked for a link between consuming dairy fat and heart disease. Here are some quotes from a Brown University press release:
Dairy products can be high in harmful saturated fat but not necessarily in risk to the heart.
Okay, let’s stop right there. Take a moment and wrap your head around that sentence. Saturated fats are harmful. Why? Because according to the Lipid Hypothesis, they cause heart disease. But they don’t necessarily pose a risk to the heart.
A newly published analysis of thousands of adults in Costa Rica found that their levels of dairy consumption had nothing to do statistically with their risk of a heart attack.
To conduct the study, [researchers] Aslibekyan and Baylin analyzed data on 3,630 middle-aged Costa Rican men and women who participated in an epidemiological study between 1994 and 2004 by co-author Hannia Campos of the Harvard School of Public Health.
Ah, so it was an observational study. Perhaps the researchers would be justified in explaining away their own results.
The researchers looked not only at the subjects’ self-reported dairy intake, but also at measurements of dairy fat biomarkers, namely 15:0 and 17:0, in their bodies.
Whoops. Not just an observational study. They actually measured biomarkers that told them how much dairy fat the participants consumed. Let’s look at the results.
What they found is that the dairy intake of people who had heart attacks was not statistically different than the intake of people who did not. After breaking people into quintiles, based on their dairy consumption amount, there was no significant linear relationship between consumption and heart risk, even among the most voracious consumers. The highest consumption quintile consumed an average of 593 grams of dairy foods a day.
Once again, stop and wrap your head around that. We’ve been told for decades to stop consuming cream and butter because the saturated fats cause heart disease. But in this study of more than 3,600 people – a study in which researchers directly measured biomarkers of dairy fat consumption – there was no relationship between consuming those arterycloggingsaturatedfats!! and heart disease.
So how do we explain this result?
Rather than suggesting that the saturated fats in dairy products are harmless, Aslibekyan and co-author Ana Baylin, an adjunct assistant professor of community health at Brown, hypothesize that other nutrients in dairy products are protective against heart disease, for all but perhaps the highest dairy consumption quintile in their study. The potentially beneficial nutrients include calcium, vitamin D, potassium, magnesium and conjugated linoleic acid (CLA).
Well, there you have it: saturated fats cause heart disease, ya see, but people who consume a lot of saturated dairy fats — even the most voracious consumers — don’t have higher rates of heart disease because … uh … because something else in the dairy products is protecting their hearts!
Awesome. Coming soon: nutrition scientists decide there must be heart-protective substances in bacon, eggs and sausage that offset the heart-killing effects of the arterycloggingsaturatedfats!!
Here’s another example of explaining away embarrassing results. In a 2010 study, researchers randomly assigned subjects to one of three groups: no change (the control group), 60 grams of whole grains for 16 weeks, or 60 grams of whole grains for 8 weeks followed by 120 grams of whole grains for 8 weeks.
These are the markers of cardiovascular health the researchers measured, according to the abstract:
BMI, percentage body fat, waist circumference; fasting plasma lipid profile, glucose and insulin; and indicators of inflammatory, coagulation, and endothelial function.
If whole grains are the wunnerful, wunnerful, health-enhancing food we’ve all been told they are, the second group should have shown improvement those health markers, and the third group should be well on its way to immortality. So let’s check the results:
Although reported WG intake was significantly increased among intervention groups, and demonstrated good participant compliance, there were no significant differences in any markers of CVD risk between groups.
No significant difference in any markers. That would mean not one.
Oh dear … and here we have our beloved USDA telling us all we need to eat more whole grains. How do we explain this result? Here’s how:
A period of 4 months may be insufficient to change the lifelong disease trajectory associated with CVD.
Riiiiiiight. Four months of consuming large servings of whole grains doesn’t affect BMI, percentage body fat, waist circumference, fasting plasma lipid profile, glucose, insulin, or indicators of inflammatory, coagulation, or endothelial function. But those whole grains may still have a positive effect on the lifelong disease trajectory associated with CVD.
Yeah, that makes perfect sense.
Well, at least these studies were published. If Ancel Keys had conducted them, the data would still be sitting in a dusty attic somewhere.
43 Comments »
Several people posted comments or sent emails with links to articles about a “rediscovered” study from the 1960s. Let’s look at some quotes from the Washington Post article:
It was one of the largest, most rigorous experiments ever conducted on an important diet question: How do fatty foods affect our health? Yet it took more than 40 years — that is, until today — for a clear picture of the results to reach the public.
The fuller results appeared Tuesday in BMJ, a medical journal, featuring some never-before-published data. Collectively, the fuller results undermine the conventional wisdom regarding dietary fat that has persisted for decades and is still enshrined in influential publications such as the U.S. government’s Dietary Guidelines for Americans. But the long-belated saga of the Minnesota Coronary Experiment may also make a broader point about how science gets done: it suggests just how difficult it can be for new evidence to see the light of day when it contradicts widely held theories.
The difficulty lies in the fact that scientists are freakin’ liars.
The story begins in the late 1960s and early ’70s, when researchers in Minnesota engaged thousands of institutionalized mental patients to compare the effects of two diets. One group of patients was fed a diet intended to lower blood cholesterol and reduce heart disease. It contained less saturated fat, less cholesterol and more vegetable oil. The other group was fed a more typical American diet.
Just as researchers expected, the special diet reduced blood cholesterol in patients.
Well then, those patients whose cholesterol dropped must have suffered fewer heart attacks and lived longer.
Today, the principles of that special diet — less saturated fat, more vegetable oils — are recommended by the Dietary Guidelines for Americans, the government’s official diet advice book.
And have been since 1980 – because of all the solid evidence supporting switching from animal fats to vegetables oils, doncha know.
Yet the fuller accounting of the Minnesota data indicates that the advice is, at best, unsupported by the massive trial. In fact, it appears to show just the opposite: Patients who lowered their cholesterol, presumably because of the special diet, actually suffered more heart-related deaths than those who did not.
The higher rate of mortality for patients on the special diet was most apparent among patients older than 64.
In other words, within the group most likely to suffer a heart attack in the first place. Hooray for vegetable oils that lower our cholesterol!
It’s not exactly clear why the full set of data from the Minnesota experiment was never published.
Oh, I think I can guess.
“Had this research been published 40 years ago, it might have changed the trajectory of diet-heart research and recommendations” said Daisy Zamora, a researcher at UNC and a lead author of the study.
And that’s why it wasn’t published.
The results of the study were never touted by the investigators. Partial results were presented at an American Heart Association conference in 1975, and it wasn’t until 1989 that some of the results were published, appearing in a medical journal known as Arteriosclerosis.
Amazing. A big, expensive study is conducted to test the hypothesis that switching from saturated fats to vegetable oils will reduce heart disease by lowering cholesterol. The results show the opposite – at a time when many Americans were being encouraged to follow exactly that advice. What kind of lousy @#$%ing scientist would bury the results instead of publishing them?
The lead investigators of the trial, noted scientists Ancel Keys and Ivan Frantz, are deceased.
You’ve gotta love Ancel Keys. The guy conducts an observational study by giving two dietary questionnaires to a whopping 30 or so people in seven countries. From this itty bitty dataset, he decides he’s proved that saturated fats cause heart disease. Meanwhile, he tries to destroy the careers of other researchers who question his findings.
Then when his own clinical study – involving thousands of patients – shows that switching to vegetable oil increases heart disease and overall mortality, he clams up and doesn’t publish the results. What an awesome scientist he was.
If this story sounds somewhat familiar, perhaps it’s because a similar study was “rediscovered” back in 2013. I wrote a post about that as well and quoted from an article in Forbes:
In an exceedingly strange turn of events, data from a clinical trial dating from the 1960s, long thought to be lost, has now been resurrected and may contribute important new information to the very contemporary controversy over recommendations about dietary fat composition.
“Exceedingly strange” has now happened twice.
One trial that actually tested the hypothesis was the Sydney Diet Heart Study, which ran from 1966 through 1973. In the trial, 458 men with coronary disease were randomized to a diet rich in linoleic acid (the predominant omega 6 PUFA in most diets) or their usual diet. Although total cholesterol was reduced by 13% in the treatment group during the study, all-cause mortality was higher in the linoleic acid group than in the control group. However, in the original publications, and consistent with the practice at the time, deaths from cardiovascular (CVD) and coronary heart disease (CHD) deaths were not published.
Now, in a new paper published in BMJ, Christopher Ramsden and colleagues report that they were able to recover and analyze data from the original magnetic tape of the Sydney Diet Heart Study. The new mortality findings are consistent:
• All cause: 17.6% in the linoleic group versus 11.8% in the control group, HR 1.62, CI 1.00-2.64)
• CV disease: 17.2% versus 11%, HR 1.70, CI 1.03-2.80
• CHD: 16.3% versus 10.1%, HR 1.74, CI 1.04-2.92
People who switched to the vegetable did worse all around: higher all-cause mortality, higher mortality from cardiovascular disease in general, higher mortality from heart disease. But as with the Minnesota study, the results didn’t see the light of day for decades. The explanation offered was that a computer data tape was misplaced and only found 40 years later.
What a strange coincidence. We have two large, well-controlled studies conducted around the same time. Both show that switching from saturated animal fats to vegetable oils actually leads to higher mortality rates (including deaths from heart disease), despite lowering cholesterol significantly. A total poke in the eye for the Lipid Hypothesis. And somehow, the results of both studies were buried for 40 years.
No wonder the researchers who crunched the “lost” Minnesota data wrote this:
Findings from the Minnesota Coronary Experiment add to growing evidence that incomplete publication has contributed to overestimation of the benefits of replacing saturated fat with vegetable oils rich in linoleic acid.
I interpret “incomplete publication” as a polite version of scientists are freakin’ liars.
Naturally, researchers who’ve spent years promoting the switch from saturated fats to vegetable oils immediately called a press conference to offer their apologies and a promise to re-evaluate their positions.
Kidding! Of course that didn’t happen. Here’s what did happen:
“The bottom line is that this report adds no useful new information and is irrelevant to current dietary recommendations that emphasize replacing saturated fat with polyunsaturated fat,” Walter Willett, chair of the nutrition department at Harvard University, said in a blog post from the school. “Many lines of evidence support this conclusion.”
He characterized the new analysis of the old experiment as “an interesting historical footnote.”
So Willett, like Ancel Keys, considers his observational studies to be rock-solid evidence, but dismisses clinical trials if the results undermine what he already “knows.”
As Max Planck said, science advances one funeral at a time. Ancel Keys is dead. A few more funerals, and we may finally see the Lipid Hypothesis end up on the Scrap Heap of Wrong Ideas, where it clearly belongs.
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