11 Serious Concerns About Vegetable Oils (No. 3 is Scary)
Saturated fat was previously blamed for raising cholesterol and causing heart disease, but this has now been disproven (1, 2). For some reason, dietary guidelines still recommend that we consume vegetable oils instead of saturated fats like butter. This includes oils like soybean oil, cottonseed oil, canola oil, safflower oil, sunflower oil and grapeseed oil (and a few others).
Vegetable oils are claimed to lower cholesterol levels, which should help prevent heart disease, the world’s biggest killer. However… many studies have raised serious concerns about these oils (3). Despite lowering LDL cholesterol, they can have disastrous consequences for other aspects of health and metabolism.
Here are 11 reasons to avoid vegetable oils like the plague.
1. Vegetable Oils Are Extremely High in Omega-6 Linoleic Acid
You’ve probably heard of Omega-3 and Omega-6 fatty acids before. These fatty acids are polyunsaturated, meaning that they have many double bonds in their chemical structure. They are often termed the essential fatty acids, because the body lacks the enzymes to produce them. These fatty acids play important roles in many biochemical pathways, including those related to inflammation, immunity and blood clotting.
The problem is… we need to get Omega-3 and Omega-6 in a certain balance. When this balance goes off, it can interrupt these important biochemical pathways (4). For example, these two types of fatty acids often compete for the same enzymes and the same spots in cell membranes (5, 6).
They often have related but opposing roles. For example, both of them are used to produce signalling molecules called eicosanoids. Eicosanoids made from Omega-6s tend to be pro-inflammatory, while those made from Omega-3s tend to be anti-inflammatory (7, 8).
Throughout evolution, we consumed balanced amounts of both Omega-3 and Omega-6 fatty acids. The problem today, is that this balance is drastically skewed towards Omega-6. Not only are people eating way too much Omega-6, but their Omega-3 intake is also incredibly low, which is a recipe for disaster. Whereas back in the day our Omega-6:Omega-3 ratio may have been about 1:1-3:1, these days it is about 16:1… which is way outside of evolutionary norms (9).
Vegetable oils are the biggest source of Omega-6 fatty acids in the diet… by far. They are particularly high in the Omega-6 fatty acid linoleic acid. This fatty acid causes a host of problems when consumed in excessive amounts… especially when Omega-3 intake is low (which is usually the case).
Bottom Line: Vegetable oils are very high in an Omega-6 fatty acid called linoleic acid, which can contribute to all sorts of problems in large amounts.