While the adverse effects of too much sugar and starch in the diet are gaining more attention, it is also essential to look at the quality of the fats we consume. Perhaps the most critical issue that still goes largely unnoticed by our society is that of oils rich in omega-6.
Vegetable oils, or, more correctly, seed oils, are rich in polyunsaturated fatty acids (PUFAs) with a high content of omega-6 linoleic acid (LA).
It is well-known and widely accepted that the ratio of omega-3 to omega-6 is very important and should be about 1:1 to 1:3. However, in our times, it is very easy to consume too much omega-6. A ratio of 1:15 or even 1:25 is not uncommon. But increasing omega-3 intake is NOT enough to offset the damage caused by too much LA. You need to minimize omega-6 intake per se to avoid damage.
The reason is that PUFAs are very susceptible to oxidation, in other words, a reaction with oxygen. When these fats oxidize, they break down into harmful subcomponents. An example of these toxic byproducts is the advanced oxidation product 4-hydroxynonenal (4-HNE). 4-HNE is a mutagen known to cause DNA damage. Studies have shown a clear link between elevated levels of 4-HNE and heart failure.
LA degrades even more rapidly to 4-HNE when the oil is heated. For this reason, cardiologists recommend avoiding fried foods. The absorption of LA and the resulting oxidation products also play an important role in cancer.
LA greatly impacts your mitochondria, the energy powerhouses of cells. Inside the mitochondrial membrane is a unique fat type called cardiolipin. Cardiolipin differs from the fat you find in fat cells, for example, in that it contains four fatty acids instead of the usual three. Which fatty acids are part of cardiolipin can vary. And each fatty acid has a different effect on mitochondrial function. There are even preferences depending on the organ. In your brain, for example, there is an increased amount of omega-3 (DHA) in cardiolipin, while more LA is incorporated in the heart.
The oxidation of cardiolipin in the mitochondria is one of the signals determining the destruction of that cell (apoptosis). Your cells know they are broken when they have too many damaged mitochondria. The process that controls this occurs mainly through the oxidation of the omega-6 fats contained in cardiolipin. So if the composition of cell membranes is richer in omega-6 fatty acids than is evolutionarily appropriate, your mitochondria are more susceptible to damage, and increased cell death occurs.
With your diet, you will ALWAYS be consuming some level of omega-6. However, limiting seed oils is the most efficient way to reduce omega-6. Plus, this will motivate you to eliminate most junk foods (chips, packaged baked goods, cookies, instant sauces) from your daily routine. Packaged food is often prepared with seed oils such as sunflower or canola oil, plus heating in the manufacturing process and long storage times.
The following applies to all oils: enjoy them cold-pressed and natural (virgin). Do not use them for cooking, as they are not heat resistant (except coconut oil). In any case, avoid oils high in omega-6 linoleic acid.
The better alternatives to cooking oils are butter and coconut oil. These are more stable and heat resistant than other fats and oils.
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Animal foods generally contain much less omega-6 linoleic acid than plant foods. However, there are a few exceptions:
Farmed salmon and chicken or pork can be high in omega-6 linoleic acid because these animals are usually fed grains that are very rich in LA.
In ruminants such as cows and sheep, this effect is less significant due to the peculiarities of their digestion.
For all animal products, grass-fed + free-range is best. If animals are fed grain, the omega-6 from the grain also accumulates in their fat. And for fish, it is best to enjoy them only if they are wild-caught.
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