Continuing our series on why fat is healthy, let us turn our attention to what I consider the most commonly referenced myth regarding fat and health.
Myth #2: Eat vegetable oils, not saturated fat.
I hear this all the time, and it is unsettling that this myth still persists in the face of recent research and when compared to ancestral eating patterns. Let’s first take a look at why saturated fat need not be avoided, and then we will discuss why vegetable oils are some of the least healthy fats (outside of trans fats which I call fake fats because they are manmade).
Saturated Fat and Cholesterol
If you have the time, the article below does a great job of discussing fat including the misconceptions about saturated fat. If you do not have the time, I have summarized what I feel are the take away points below.First, there has been little research showing any link between saturated fat and heart disease, and new information is coming out that other factors such as triglyceride levels and lipoprotein type (not amount) are more important risk factors. The original studies showing that saturated fat and cholesterol relate to heart disease were based on correlative data with little actually research.
Second, cholesterol needs to be better understood. Cholesterol is an important molecule in the body that is manufactured within the cells and is TRANSPORTED by lipoproteins (LDL, HDL, etc). Cholesterol is important for the synthesis of bile acids, steroid hormones, and vitamin D. It is also required for building and maintaining cell membranes. Lipoproteins, on the other hand, are transport molecules that move fat and cholesterol around the body. There are three main types of lipoproteins: VLDL, LDL, and HDL. VLDL is responsible for transporting triglycerides (fat). LDL is responsible for transporting cholesterol from the liver to the cells of the body. HDL is responsible for transporting cholesterol back from the cells to the liver (to be recycled). Studies are starting to find that when VLDL is high (high triglyceride levels), and HDL is low, LDL starts becoming small and dense. This increases the risk that these particles will get stuck in the arterial lining, leading to inflammation and plaque build-up. Studies are also starting to show that the ratio of HDL to LDL is more important than total cholesterol. How can you raise HDL? Eat more fat (saturated included), and exercise more.
Finally, triglyceride levels and small, dense LDL particles (the two things that are related to heart issues) are more associated with high-carb diets. Our bodies only need a limited amount of carbohydrate intake to function optimally, so any excess carbs will be turned to fat and stored for future use. Insulin plays a big role in this, which, as we talked about last time, is an important hormone in blood sugar regulation and fat storage. While the link between high carb and high triglyceride levels is become more apparent, there have only been comparative studies on LDL particle size. Basically, we know that when you compare high-fat diets to high-carb diets, the high-fat diet will result in lower levels of small, dense particles. So it looks like high-fat, with adequate saturated fat in the diet is the way to go to get your cholesterol in check!
Below I have posted a number of other links that will give you more information on these topics.
Vegetable Oils and Polyunsaturated Fats
If saturated fat is not bad for us (and is actually very important for optimal health), do we still need to have vegetable oils in our diet?? No! Not only do we not need vegetable oils, I will argue that they are actually unhealthy.
Vegetable oils are predominantly polyunsaturated, meaning they have more than one double bond within the molecule. Why is this important? Because more double bonds = a less stable molecule. They breakdown easily, become rancid with little exposure to light or heat, and are much more likely to become toxic in our bodies. In other words, cooking with vegetable oils is definitely out, but even without heat, you are taking a risk. Many vegetable fats are rancid before they are even opened due to light contamination.
The second issue with veggie oils is that they have an unfavorable ratio of omega-6 to omega-3 fatty acids. Omega-3 has been getting press due to its heart-healthy properties, and one of the main health benefits is that it balances out the overwhelming quantity of omega-6 fats that Americans consume each day. Between the consumption of corn-fed animals, vegetable oils, grains, nuts, beans, and dairy, the average American eats up to 20x MORE omega-6 than omega-3 when a healthy ratio would be closer to 2:1. While fish oil and other such omega-3 supplements can help, there is just no way to counteract such high quantities of omega-6. We need to decrease the amount of omega-6 intake, starting with eliminating vegetable oils.
Myth Debunked
So there you have it. Stop avoiding saturated fat and start replacing your high-carb/vegetable-oil-as-the-main-fat diets with more saturated fat (animal products in general) and fat in general. As you make this transition, one important thing to know is that there is a BIG difference between grass-fed/wild animal products (and the fat that comes with them) and corn-fed, farmed animal products. If you can afford to eat grass-fed/wild, go for it. If you cannot, stick with leaner meats as the toxins that these animals are exposed to will be stored in the fat. You can supplement your fat by using coconut oil/milk, butter (you can find grass-fed at whole foods), or by rendering your own fat (or you can easily buy some from the grass-fed beef stand at the farmers market). All of these are great for cooking as saturated fat tends to be more stable when exposed to heat.
Next week, we will conclude this series with some of my thoughts on the psychology of fat and more strategies on how to best increase the fat in your diet.
No comments:
Post a Comment