In 2014, an article was published in the Annals of Internal Medicine that challenged what many of us believed about dietary fat. This article reviewed 32 research articles looking at the association between dietary fat and coronary artery disease. The article concluded that the evidence did not support the current guidelines for low consumption of saturated fat and high consumption of polyunsaturated fat.
Here is what the article found:
- saturated fat consumption had no effect on coronary artery disease
- omega-6 fatty acids had no effect on coronary artery disease
- trans fats increased the incidence of coronary artery disease
- omega-3 fatty acids reduce the risk of coronary artery disease
This research, along with some other recent articles, have changed the way many people eat. But is this good? Is this bad? What does this really mean? And most importantly, does this mean that I can eat as much bacon as I want?
What else are you eating?
In science and medicine, we often become micro-focused on topics and we completely miss the point. This is what I have seen with the topic of dietary fat and particularly saturated fat. When someone asks me if they can eat bacon, or butter, or eggs, I always ask them what else they are eating? Because fat consumption does not exist in a vacuum in the body. And biochemically speaking, fat is dangerous in the body when sugar is high. Artery-blocking plaques only form when fat is oxidized in the blood. What promotes fat oxidation? Weak antioxidant systems, inflammation, and high blood sugar.
So the bottom line is that if you eat a lot of processed carbohydrates and refined sugar, then you should eat less saturated fat and possibly less dietary fat in general. Basically, if your diet has lots of bread, pasta, and baked goods, then butter, bacon, and red meat are not going to be healthy for you.
But, if your diet is over 50% plant based, if you get 7-9 servings of vegetables a day and avoid processed grains and sugars, then eating butter, meats higher in saturated fat and coconut oil will probably not be detrimental to your health.
What is the current state of your health?
This is another important contextual question when it comes to dietary fats. Do you already have cardiovascular disease? Do you have diabetes? Have you been diagnosed with metabolic syndrome? If the answer to any of these questions is yes, then dietary fat can be problematic.
What about genetics?
Another important factor to consider is that depending on your genetics, you may or may not be "sensitive" to saturated fats. Studies have found that eating a more than 22 grams of saturated fat a day with one variation of the APOA2 gene increases your risk of obesity by 67%. But if you have a different variation of the gene, your saturated fat consumption does not affect your obesity risk.
How much fat should you eat?
With diet such as the Paleo or Ketogenic diet promoting higher fat intake, the question of how much fat to eat is a common one. Unlike a lot of practitioners, I don't believe in a one-size-fits-all dietary approach. For some people, getting 20% or less calories from fat may be optimal. For other, getting 30%, 40%, or even 50% may be optimal. This all depends on your genetics, the health of your liver, your hormones, and your metabolism. So, there is no simple answer.
What fats should you eat?
While the complete answer to this question must be individualized, there are a few generalizations we can make. Typically, fats found in whole foods are not problematic because these fats occur in balance with other macronutrients and micronutrients. These foods include fish, nuts, seeds, and avocados. With some exceptions, fats in these foods are considered healthy for most everyone and I typically don't see a need to limit consumption of these kinds of fats.
When we do need to use fat extracts (such as oil), I recommend using small amounts of avocado oil or coconut oil for cooking; coconut oil for baking; and olive oil, hempseed oil or flaxseed oil for salad dressings. But specific recommendations for the amounts and types of these oils will depend on you and your health.
What fats should you avoid?
Everyone should avoid trans fat. These are fats that are not found in nature but occur in a chemical process. These fats are found in margarine and other solidified vegetable oils and are often in baked goods. And these fats do contribute to cardiovascular disease, so everyone should avoid trans fats.
Other fats that I recommend avoiding include refined oils such as vegetable oils, canola oil, safflower oil, sunflower oil, and corn oil. These oils are high in omega-6 fatty acids. And even though the article found that these oils do not affect coronary artery disease, we do know that they promote a more inflammatory state in the body. So I recommend avoiding these oils as much as possible.
Basically, when it comes to dietary fat or any other aspect of your diet, you need to figure out what is best for you based on your genetics, biochemistry and physiology. And that may look different than what your friends are doing or even what that one study says. So find a doctor or practitioner that has the knowledge and the skills to truly do personalized nutrition.
- Corella D et al. APOA2, dietary fat, and body mass index: replication of a gene- diet interaction in 3 independent populations. Archives of Internal Medicine. 2009;169(20):1897-906.
I'm Dr. Carly and my mission is to create a health revolution. I believe that another prescription is not the answer. I believe in using natural therapies that go beyond the symptoms. And I believe that doctors should spend way more than 7 minutes with a patient