More evidence from the best controlled randomised controlled trials found that replacing saturated fats with mostly vegetable-seed oils (n-6 PUFA) does not reduce coronary heart disease mortality or total mortality.

So why does the heart foundation continue to sell margarine and vegetable oils to the public?

A cornerstone of outdated dietary advice is the recommendation to reduce the intake of saturated fatty acids (SFA) as a means of reducing the risk of coronary heart disease (CHD). There are a few variations of this recommendation, these include: 1) advice to reduce the intake of SFA; 2) advice to replace SFA with monounsaturated fatty acids (MUFA) and mostly n-6 polyunsaturated fatty acids (PUFA); and 3) advice to replace SFA with mostly n-6 PUFA. It also recommends margarine and vegetable oils instead of butter and animal fats. However, the evidence for this recommendation has been questioned by recent a number of meta-analyses of observational studies and clinical trials. These studies have consistently found that the intake of SFA is not independently associated with the incidence of CHD.

Unfortunately, mega 6 oils such as corn, safflower, cottonseed, sunflower, and soya are now in nearly all our foods. Apart from the obvious consumption of vegetable oils and margarine you buy in the supermarket—which I hope you are now not going to buy—Omega 6 oils are hidden in most foods. You will find vegetable oils in just about every processed and semi-processed food including bread, cakes, and breakfast cereals and in lots of the plant-based drinks like almond or soya milk the main ingredient is often vegetable oil. All the takeaway foods, frozen and packaged dinners have Omega 6 oils. Even the “new” Mediterranean diet is laden with Omega 6 oils. When you buy olives, pesto sauce, sundried tomatoes or anything soaking in oil it is now vegetable oil in which it is soaked, not olive oil because vegetable oil is cheaper, unless you go to Italy where most foods are still soaked in olive oil. It is almost impossible to get away from the excess of Omega 6 oils. Time to read the labels! Factory produced eggs have 20 times more Omega 6 than Omega 3 compared to free-range eggs, which have a ratio of 1:1. Similarly, grain-fed beef (which I do not recommend you eat) has around 20:1 Omega 6 to Omega 3 oils because the cows are fed grains rich in Omega 6 oils. Alpha linolenic acid is found in the grass and is converted into the important Omega 3 oils by the animals. It is found only in grass-fed animals. Grass-fed cows are also a lot less stressed and have as a result lower levels of inflammation.