Good fats – bad fats
As described above, there are different types of fatty acids, namely the saturated and then the monounsaturated and polyunsaturated fatty acids. Among the polyunsaturated ones, the omega-3 and omega-6 fatty acids also play a special role.
Most common in today’s diet are saturated fats. Every animal fat source consists to a large extent of it. An exception are all marine fish, but I’ll come to that later. Saturated fatty acids are also responsible for many syndromes, they not only promote cardiovascular diseases but also diseases such as asthma, atopic dermatitis or rheumatoid arthritis. The problem in today’s society is that just about every food item has been industrially treated in some way and not infrequently has been provided with a multitude of fats, since fat is also a very potent flavor carrier in the diet.
Now, we know that the body can also produce saturated fatty acids itself, so that supply from outside sources is actually not (or only partially) required and should be minimized as much as possible. Unlike the monounsaturated and polyunsaturated fatty acids. These cannot be produced by the body itself, which is why they are also called essential fatty acids and should occupy an important position in food selection.
Omega-3 and omega-6 fatty acids are essential fatty acids that have special functions in the human body. This is especially true with regard to the production of the prostaglandins mentioned above. The omega-3 fatty acids alpha-linolenic acid (ALA), docosoheaxaic acid (DHA) and eicosapentaenoic acid (EPA) are anti-inflammatory prostaglandins, while the omega-6 fatty acids linoleic acid and arachidonic acid (AA) are pro-inflammatory prostaglandins. Both types are needed by the body, but they should be provided in a certain ratio to each other. While the diet of the Stone Age people still had a ratio of omega-3 fatty acids to the omega-6 fatty acids of about 1: 1, the diet of a hundred years ago, a ratio of omega-3 / omega-6 ranged from 1: 3 to 1:10 (this is still considered satisfactory), but people in modern industrial societies feed on so much linoleic and arachidonic acid and at the same time so few omega-3 fatty acids that their diet has an omega-3 / omega-6 ratio of 1:10 to 1:50. Here, even the German Society of Nutrition called a ratio between 1: 5 and 1:15, for bodybuilder this should still be between 1: 3 and 1:10. Overall, 3.5% of total energy intake from these two types of fatty acids is recommended. Incidentally, the quantitative ratio of the two fatty acids plays a more important role than the absolute amount itself, because both fatty acids compete for the same receptors in the body, so that too much of the one fatty acid can cause a deficiency of the other.
For omega-3 fatty acids, alpha-linolenic acid is found mainly in green leafy vegetables and some vegetable oils (e.g. linseed, canola and soybean oil). Eicosapentaenoic acid and docosahexaenoic acid are found mainly in fish and fish oil. Fat fish species such as mackerel, herring or salmon are particularly rich in omega-3 fatty acids.
|Fig.1: Omega-3 quantities in fish species|
|Species||Omega-3/100 g fish|
|Other low-fat fish||<100 mg|
Fish oil capsules available in health food stores usually contain about 25% omega-3 fatty acids. Of the vegetable oils, linseed oil with a content of 58% of the omega-3 fatty acid alpha-linolenic acid should be emphasized. Then comes the hemp oil with 20%, followed by walnut, soybean, rapeseed and wheat germ oil at levels of 5-7%. All other oils have an omega-3 fatty acid content of less than one percent.
Plants, on the other hand, are the most important sources of omega-6 fatty acids. Many types of seeds (such as cereals, cottonseeds, safflower seeds, soybeans) are rich in linoleic acid. Margarines that contain vegetable oils as their main ingredient are also good sources of linoleic acid
|Fig.2: Linoleic acid content of oils|
|Oil||Portion of linoleic acid|
However, as the likelihood of omega-3 fatty acid deficiency is generally greater than the omega-6 fatty acid excess, the diet should be primarily oriented towards the eating enough omega-3s.