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The Skinny on Fat - Part I

Rachel Lett, RNutr.

Chief Care Officer

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Word on the street is, ‘fat is back’. No longer to be feared, dietary fat is your weapon toward greater health, and proven to reverse diabetes 💪

Maybe you’ve already heard this from a work colleague who toots the wonders of avocados and coconut oil at every lunchtime. You want to believe them. You see how much energy they have and how their health radiates. Yet that nagging voice in the back of your head tells you

“It’s just a fad diet. Fat is to be feared, it’s what the experts have said for decades.”

News articles about nutrition change as quick as a flash and are always conflicting. It’s very unfair, and near impossible for you to know what you should and shouldn’t eat. Yes, I’m an accredited nutritionist, but why should you just take my word for it if I say “eat more fat, especially saturated.”

In a two part series, I want to explain the origins of the low-fat diet, and why we need this vital nutrient for health and wellbeing. After that, you can make up your own mind. 🤔

A brief history of the low-fat diet

Let’s begin with Ancel Keys, a physiologist who had a very persuasive voice in the medical and dietary industry. He hypothesised that saturated fat was the leading cause of heart disease. This was based on the idea that saturated fat raises cholesterol levels which ‘furrs’ the arterial wall and thus, causes heart attacks 💔.

In an attempt to prove his hypothesis, Keys published the Seven Countries Study, an epidemiology study comparing saturated fat consumption and the rate of heart disease in seven countries. Epidemiology studies the prevalence of disease and determinants in different populations —the resulting evidence is weak, and at best, these kind of studies help develop a hypothesis.

The Seven Countries study had a less-than rigorous scientific approach. After studying 22 countries, only 7 made the cut. France was omitted, where cardiovascular death was low but diets were rich in saturated fat—what we now know as “the French paradox”.

It’s believed that Keys ‘cherry picked’ the countries to make his case stronger—this is a rather controversial topic.

In addition, he studied populations during post war and lent when rationing was still prevalent—diets were disrupted and ‘out of the norm’.

Keys also failed to look at the finer detail, like what countries had a high intake of sugar or processed food—other factors that could have caused heart disease were overlooked. 🧐

In the end, the Seven Countries study only proved association between saturated fat and cardiovascular disease, not causation. Nonetheless, this study forged a deep belief that saturated fat causes cardiovascular disease, and we’re still paying the price for it.

Deep into the veins of nutritional guidelines‍

Keys was a charismatic and influential character who positioned himself close to people with power. In 1955, President Eisenhower had a sudden heart attack, which brought cardiovascular disease to the forefront of concern. Keys advised Eisenhower’s physician, and later it was publicly announced that people should eat less saturated fat to prevent heart disease.

Keys joined the American Heart Association (AHA)❤️ in 1961, and at the same time they started advising a low saturated fat diet. Demonising saturated fats paved the way for trans-fats to take over(which we know have a detrimental effect on health). In return, this conveniently boosted profits for Procter and Gamble, the makers of Crisco (vegetable shortening), who had donated $1.7million to AHA 💰.

In the same year, Keys made a name for himself appearing on the front cover of Time Magazine. Backed by guidelines, it wasn’t long before the low-fat diet took hold and rooted itself deep into society.

Despite research showing no link between saturated fat and heart disease, fat phobia is still deeply embedded in our thinking, and seems impossible to shrug off.

Given that the evidence to support the fat hypothesis is weak, recommendations have silently abandoned the low-fat diet. However, their efforts have been so discreet, no one has noticed — I imagine this is embarrassment on their behalf. Alas, we’re still living by the same flawed research that infiltrated our diets.

The low-fat diet was inappropriately recommended to the nation, and has unfortunately shadowed our diets for decades. With this knowledge 🤓 you have granted yourself the liberty to embrace healthy fats on a daily bases—enjoy them! 😋

It is time for us to unlearn the propaganda, and immerse ourselves in sound research and food that nourishes our bodies.

Ready to learn more about fat?

In the next article I will be discussing the functions of fat in the body, and why we need this vital nutrient to survive and thrive. Fats are not to be feared, but to be relished and enjoyed!

If you’re interested in joining Span, download our mobile app on or contact us at to learn more.

Till next time, 🙌🏽

I’m sure you’re curious about the science behind all this 🔬 Here are some recent medical publications about this topic:

And some books:
• The Big Fat Surprise: why butter, meat, and cheese belong in a healthy diet— by Nina Teicholz
• Fat for Fuel: A Revolutionary Diet to Combat Cancer, Boost Brain Power, and Increase Your Energy — by Dr Joseph Mercola
• Nourishing Fats: Why We Need Animal Fats for Health and Happiness —by Sally Fallon Morell

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