A couple of years ago, I did a series on dietary fats and the role they play in our health. My readership has more than tripled since then, and I thought it would be a good time to re-run one of my best posts on the subject. Enjoy, and feel free to to tell me I’m full of it if you wish. It will be an interesting conversation.
Last Friday I wrote a post about a study published in the European Journal of Internal Medicine implicating the high consumption of carbohydrates in the development of Alzheimer’s and other neurodegenerative diseases – basically what it came down to was consuming excess carbohydrates and insufficient amounts of fat and cholesterol can kill your brain.
Some of you took exception to that. Which is fine; we’ve been taught, over the last 60 years – and it’s really been driven home in the last 30 – that the consumption of saturated fat and cholesterol are responsible for everything from strokes to heart attacks to various forms of cancer to (of course) obesity. We’ve been taught that “whole” grains are our salvation – the very key to good health and a long life. We’ve been taught that if we’ll just replace all those nasty animal fats with liquid-at-room-temperature vegetable oils** our arteries will run free and clear and all will be well and all manner of things will be well.
Bullshit. (Sorry, but that’s exactly what it is.)
All fatty acids are merely chains of carbon atoms with pairs of hydrogen atoms attached. Saturated fatty acids have both hydrogen atoms at each link; monounsaturated fats are missing one pair, and polyunsaturated fats are missing two or more pairs – saturated fats are literally saturated with hydrogen. As a result, they are solid at room temperature, have a higher melting point than other fats and are more stable – they do not go rancid as quickly as monounsaturated and polyunsaturated fats.
Even then, all saturated fats are not the same – some carbon chains are longer than others; generally, short and medium chain saturated fatty acids are more easily converted to energy than long chain SFAs, but all are essential to your continued good health.
Long chain SFAs pad the soles of your feet, the palms of your hands and your behind; they also cushion your internal organs and protect them from injury. Short and medium chain SFAs such as caproic acid, caprylic acid, capric acid and lauric acid are easily absorbed through the intestines; they’re delivered directly to the liver and are an excellent source of energy. In fact, the saturated fats stearic acid and palmitic acid are the preferred source of energy for the heart, which is a major contradiction to the idea that saturated fat causes heart disease.
More than half of your brain consists of fat and cholesterol, and anywhere from a third to more than half of the fat is saturated. Both saturated fat and cholesterol represent a significant portion of the myelin sheath that surrounds nerve fibers and preserves proper function of the brain and nervous system. If this protective layer is compromised in any way, it can lead to a number of neurological disorders (such as Alzheimer’s).
If that’s not enough for you, saturated fat also:
~ Allows your body to utilize fat-soluble vitamins (A, D, E and K)
~ Promotes healthy cell function (the membrane of each cell in your body is 50% saturated fat)
~ Is essential for proper bone development
~ Is important for your immune system to function properly
~ Is essential for healthy lung function
~ Protects the body against toxins
~ Helps protect against skin cancer
~ Is essential to the body’s proper utilization of essential fatty acids like Omega 3
And why, if saturated fat is so bad for you, is there so much of it in your body? Almost 50 percent of your body fat (whether you’re obese or not) is saturated, and if you don’t consume it your body will convert carbohydrates into saturated fat. That is how important it is.
One reader left a comment saying, “I agree some fats are good. BUT I have a husband who is involved daily with surgeries on the GI tract. He sees first hand the insides of people with high fat diets and those with low fat diets. Unfortunately for me, he brings home photos and videos to share with me. Having seen, first hand, what a high saturated fat does to the inside of our bodies … I don’t think it’s healthy or safe.”
I can understand how something like that would definitely make a person wary of saturated fats in the diet. However, there are problems with this reasoning: first and foremost the medical community’s insistence on lumping saturated fats together with trans fats, which ARE bad for you and ARE implicated in a multitude of health problems, including colorectal cancer as well as heart disease.
In the 1980s we began to get a lot of advice to cut saturated fats out of our diets – we were told to avoid red meat, eat chicken without the skin and replace our butter with margarine. Tropical oils were removed from processed foods and replaced with partially hydrogenated vegetable oils. Restaurants stopped cooking with animal fats in favor of those same vegetable oils. This was largely based on research done at the Harvard School of Public Health and included data from the Nurses Study II, which monitors the long-term health condition of nearly 116,000 women, and the Health Professionals Study, which monitors the long-term health condition of 52,000 men.
These studies showed strong evidence that saturated fat caused heart disease and cancer. But in the 1990s, researchers began to take trans fats into account, separate from saturated fats, and found that the participants in these studies who ate more margarine and vegetable oils and shortenings had higher rates of cancer, not those who consumed butter, eggs, cheese and meat.
This is why observational studies can be so misleading, and why controlled clinical trials are so necessary. Just observing the behavior or habits of a group of people can be deceptive, especially if you’re looking for something specific. It’s very easy to say, “These people have a high fat diet and higher rates of heart disease and cancer; dietary fat must cause these diseases!” while completely ignoring the fact that those same diets are also high in refined carbohydrates, high fructose corn syrup and/or other refined sugars and that the majority of the fat in the diet are trans fats.
The latter are known as confounding variables, and they should be taken into consideration not only in individuals with the high fat diets, but those with low fat diets as well. People who eat low fat diets tend to be more health conscious than those who eat a high fat diet. They exercise more; eat more green leafy vegetables and less sugar and processed foods. They tend not to smoke or drink alcohol, and they generally consume far fewer trans fats. All of these things need to be taken into consideration, but unfortunately most medical professionals do not – they’ve been taught that saturated fat is the root of all dietary evil and that’s that. Case closed.
We’ve been vilifying dietary fat, especially saturated fats, for more than half a century and we’ve just been getting fatter and sicker – it’s time to understand the importance of these fats in our diet and our good health. I’m not suggesting you consume it to the exclusion of all else, but I am saying that if you avoid saturated fat because you believe it’s going to eventually kill you, that’s simply not true.
**”Vegetable oil” is a misnomer – corn is a grain, soy is a legume and rapeseed (masquerading under the harmless-sounding “Canola”) and cottonseed are, well, seeds. There are no commercial-grade food oils from vegetables.