Dietary Fats and Health
Our regular readers know that we have been recommending a lower carbohydrate diet, more along the lines of the paleo diet that is more in vogue lately. We are not completely on board with the diet, for we would prefer meats with a higher concentration of fats (such as chuck roast and pork) and we believe eating dairy is fine as long as it is the high fat stuff like half and half or heavy whipping cream. Let me add a bit more clarity: I would say that our diet aligns more closely with the high fat/low carb paradigm with a heavy dose of veggies. There is no doubt that we are eating far more fat than what the mainstream nutritionists would recommend for good health.
After all, a high fat diet will clog the arteries and lead to heart disease, right?
Not necessarily. New research is showing that a high fat diet is not as devastating on our health as we thought. However, the types of fat do make a difference.
In this blog, we will delve into the different types of fat, and whether or not they should be a big part of our diet.
Saturated fat. What makes fat saturated is the fact that all of the available carbon bonds are tied up with a hydrogen atom. This is the reason why saturated fats are solid at room temperature.
Interestingly, and still little known about saturated fats is that this type of fat is very stable, and not prone to spoilage and oxidation. Moreover, saturated fats are heat-resistant and necessary for many bodily functions. For example, saturated fats create a surfactant that covers the lungs that keeps them lubricated and prevents them from drying out. Cell membranes consist of approximately 50% saturated fat and gives the cells the needed stiffness and integrity for proper functioning. One other point I feel is very important to make: The brain consists mainly of fat (most of it saturated) and cholesterol (imagine that), so a diet rich in saturated fats gives the brain the raw materials needed to stay healthy.
Additionally, research is showing no correlation with high saturated fat consumption and heart disease. The evidence is not there.
Polyunsaturated fat. To properly define what a polyunsaturated fat is, we need to be clear about what an unsaturated fat is. An unsaturated fat is a fat whose carbon chain can absorb more hydrogen atoms. Thus, polyunsaturated fat is a fat that has more than one double or triple valence bond per molecule. The many “open-ended” bonds creates a promotive environment for oxidation, which in general is not good for the body. This suggests that polyunsaturated fats should be avoided, but it is not that simple. There are health benefits to some polyunsaturated fats, but not so much for others. This has to do with the difference between Omega-3 fatty acids and Omega-6 fatty acids. I will get into this in a moment.
Monounsaturated fat. Monounsaturated fats are fats that have one double bond in the fatty chain with all the remaining carbon atoms being single bonded. Due to the fact that monounsaturated fats have one double bond, they are semi-solid at room temperature. Additionally, monounsaturated fats are actually quite stable (maybe not as stable as saturated fats, but pretty stable none the less). As a matter of fact, monounsaturated fats are highly resistant to heat damage. So go ahead and use that olive oil for sauteing.
Trans-unsaturated fat. The better known name for trans-unsaturated fats are trans-fats. Trans-fats are made in small amounts in nature…and are quite good for you. However, the better known version of trans-fats are the types of fat that are industrially made from vegetable oils. The vegetable oils go through a process of hydrogenation to make the oil more solid at room temperature (think margarine) and to be used for processed and packaged foods because they have a longer shelf life than vegetable oils, and they are far cheaper to use. Furthermore, trans fats are widely used by restaurants for frying. There is strong evidence suggesting that regular consumption of trans-fats increase the risk or heart disease.
The Omega’s. Both Omega 3 and Omega 6 fatty acids are polyunsaturated as I mentioned above, so they are more likely to oxidize than the saturated fats, but they are still important for our health. Researchers first learned about the value of Omega-3 fatty acids for heart health back in the 1970’s when they observed that the Eskimos of Greenland had lower cholesterol levels than the Danish or other western groups. An examination of their diets showed that they ate a very high fat diet with hardly any vegetables at all. A large portion of the diet consisted of fat from fish, and they had no signs of heart disease. Moreover, Omega-3 fatty acids are known to:
- Regulate blood clotting
- Play an important role in cell membrane functioning
- Prevent or improve inflammation
- Improve cholesterol levels
- Lower triglycerides
We also need the Omega-6 fatty acids in our diet for good health too, but the ratio in our modern diet of Omega-3 to Omega-6 fatty acids are way out of proportion. The ratio of Omega-6 to Omega-3 fatty acid intake should be around 1:1, and some researchers say even a ratio of 4:1 can still be healthy, but the ratio is way off kilter. It averages anywhere from 20:1 to 50:1! High Omega-6 ratios promote systemic inflammation which scientists say is the cause of heart disease, diabetes, premature aging and cancer among others. The large prevalence of Omega-6’s come from vegetable oils such as sunflower, safflower, corn, soy, and canola. These oils became dominant in restaurant food preparation and packaged foods.
So where does that leave us? No doubt we do need fat in our diets for good health, and most certainly much more than we previously thought, but we still have to be selective. Since there are no healthy benefits to trans-fats in the diet, and especially since trans-fats have been shown to promote heart disease, we should not consume trans-fats at all. That takes out all of the packaged foods, and we must stay away from the fried foods at the restaurant. I am aware that restaurants are trying to change to healthier oils for frying, and some may have made the changes, but I still think it is prudent to just stay away from the fried foods, period.
Do not use any of the vegetable oils that are liquid at room temperature for sauteing or frying at home, with the exception of olive oil or even avocado oil. Truth be told, it is nearly impossible to actually find a true Olive oil blend in the store. Most of them have a olive-oil, polyunsaturated oil blend. Because of this, Sharon and I no longer use olive oil. We simply switched to avocado oil for use on our salads.
Speaking of which, what we do use for sauteing is either coconut oil (saturated) or butter (saturated). We use beef tallow from time to time as well (also saturated).
It is of my opinion that we all should increase our intake of fats and at the same time decrease our intake of carbohydrates to a large degree. I would go so far as to suggest we should get roughly 60 to 70% of our calories from fat, cut total carbohydrate consumption down to 15 to 30%, and keep our protein intake about the same. Thus we should eat far more saturated fats, for it is not wise to increase trans-fats or our Omega-6 intake for that matter.
Saturated fats have been vilified too much for way too long. It is time we bring it back into our diets.