When the Consensus is Wrong: The story of Dietary Fat

Smart people and respected institutions are sometimes completely wrong.

With the backdrop of the (hopefully) outgoing administration of Donald Trump, I’ve been thinking about one of his central issues: free trade. Trump may not have solutions, but he sure can identify problems. Economists of the 1990s were fervently pro-free trade, meaning they favored allowing corporations to outsource their labor to the third world and sell them in the United States. First world countries would be full of well paid knowledge workers and the manufacturing would be handled by the third world. This would give cheap goods to the first world and allow struggling economies to develop a large middle class. Economists dismissed as xenophobic, unsophisticated and “silly”—to use Paul Krugman’s preferred epithet—anyone who questioned the free trade consensus. Politicians, academics, business leaders, The IMF and the European Union all spoke with one voice: free trade and globalization is the way of the future. “Rejecting free trade was like rejecting the sunrise” George Packer wrote.

But the sun didn’t rise. The doubters had a point and many people were left behind in this process. Wages fell dramatically for low skilled workers in America and Europe. Unemployment rose. Local economies crumbled.

Not only did the mainstream get it so wrong, but they were smug about it too. The rise of India and China has shown that they were half right, but nevertheless, for many the dismal science has become the disreputable science.

In spite of this, nutritionists wish they had the stature of economists. At the same time as economists were eagerly giving away the American manufacturing base, nutritionists were asking people to throw away their butter and buy margarine–an embarrassing claim given that trans-fats were later shown to be even worse than the saturated fats in butter.

Some vegans are prone to telling a story against fat that was partly proven wrong.

Too often we want things to be binary. We want fat (or free trade) to be all good or all bad. The truth is mixed. Once researchers saw that obesity and cholesterol levels were linked to heart disease, the consensus was that low-fat foods were the way to improve American diets.

Furthermore, obesity has long been a concern for Americans and fat is far more calorie dense than either protein or carbohydrates (9 calories per gram versus 4 calories per gram for the latter two). If you were keeping the number of grams of food constant, the way to lose weight would be to consume fewer calories from fat.

Since the 1950s, researchers have known that high saturated fat intake leads to higher cholesterol, which leads to elevated risk of heart disease.

Academic and government based advice got way ahead of the science. Food producers began marketing foods as low-fat and Americans began eating them as if dietary fat was the only way you could gain body fat. I wonder if this is in some small way an unfortunate byproduct of the fact that we have the same word for dietary and body fat.

Food producers were taking away fat content, but adding sugar and simple carbs. Low-fat labeled foods weren’t necessarily any lower in calories than higher fat counterparts. These low-fat foods may also be lower in satiety, meaning they don’t make you feel full. These foods also have the downside of being hyper palatable, meaning they light up the brain’s reward circuitry and are hard to stop eating. Ever notice how at the end of the meal you can squeeze in desert, when you wouldn’t dream of having another helping of vegetables?

Americans were reducing their fat intake and upping their calorie intake.

This wasn’t a failure local to private research and public companies. This was government-backed dietary advice. First, researchers discovered the role of cholesterol and overstated the role that dietary cholesterol plays in blood cholesterol. Then they made the aforementioned mistake of encouraging margarine over butter, which was a consequential mistake, which put vulnerable, earnest American’s lives at risk. https://nationalpost.com/health/butter-is-alright-but-margarine-just-might-kill-you-massive-canadian-study-finds

The public health interventions did not work. Obesity levels continued to rise. This led to a backlash. Many experts still contend that reducing fat intake is a useful first step in dietary intervention for overweight people. It’s just vital to monitor total calories, eat a balanced diet, avoid hyper-palatable foods, and consider satiety as well. More controversial interpretations, such as put forth by Gary Taubes, contend that the guidelines were dead wrong. Bacon and eggs are healthy; carbs and sugar are the enemy. Taubes even believes that the mainstream weight loss paradigm of calories-in-calories-out is broken given that it doesn’t account for hormonal responses (particularly insulin) to carbs in comparison to protein.

For better or worse, this failure of public health and writers like Taubes have fueled an explosion of interest in low carb diets, which have only gotten more radical over time. We’ve gone from Atkins/low-carb to paleo to keto to carnivore.

I wonder if there’s even a relationship between this food trend and societal attitudes towards body fat. In the 1990s, heroin chic was in and models and actresses looked downright underweight. Curvy (AKA thicc) figures are in today. It cannot help the vegan cause that salads and black beans don’t seem like the way to get a body Kim Kardashian.

This is why it’s so damaging when expert consensus is wrong in any way. It leads to a reactionary backlash and a certain number of people pendulum swinging the other way, with disastrous consequences.

This is a pattern that matches the free trade story. Free trade is only a piece of the story of Donald Trump’s election in 2016, but it is an important piece. Trump spoke to a segment of the electorate that mainstream political discourse on both sides had forgotten about. The endless op-eds about the two Americas, whether that be rich versus poor, urban versus rural, college educated vs non college educated, leavers vs stayers, or people who care about politics and people who don’t, all share the feature of a smaller ruling class and a larger underclass on the other side.

And that smaller segment is prone to being smug and wrong. But in response the larger segment is prone to being conspiratorial and taken in by misinformation. Contrary to what the low carb community would have you believe, nutritionists do not have any reason to lie about fat. The science is solid that relying heavily on steak, eggs and bacon is not good for you. Certainly, not sustainable in the long term.

There is a core vocal minority that embraces animal based saturated fat and this advice trickles down to a larger segment of the population. Grass fed meats are in vogue. Joe Rogan tried the carnivore diet to lose weight and has guests that promote this viewpoint (to be fair, he’s willing to have a debate on this general topic, but it’s clear where his heart lies). 70% of the population meets or exceeds recommendations for saturated fats. Both men and women of all age groups exceed recommendations on average.

And veganism has its own extreme contingent which clings tightly to the older story about fats, promoting diets that are nearly exclusively fruits and vegetables, to the detriment of fats and proteins. Some vegans are prone to telling that story about fat that was partly proven wrong. See the diet plans of the average vegan fitness model influencer or even Dr. John McDougal for examples. We must resist being goaded into taking the polar opposite position of our ideological opponents.

Dietary fat is satisfying and helps us feel full. As plant based diets have grown we’re already seeing avocados, coconut products, chia seeds, flaxseed, dark chocolate and mock meats as significant food trends. These fats allow us to take advantage of some of the benefits of satiety and indulgence necessary to maintain a vegan diet while avoiding the health consequences that come along with animal based fats. This is not a particularly difficult tight rope to walk and I hope most vegans can continue. I can only hope that we leave the carnivore diets and low carb dogma behind as we leave our current president.