Fats are always bad

Good fat, bad fat

Prof. Jahreis, what do you mean by “good” and “bad” fats?

First of all, I would like to make something clear: Fats are one of the basic nutrients and are essential for our health. It only becomes unhealthy if we eat too much of it. And we should be careful which fats we choose. The decisive factor is their content of saturated and unsaturated fatty acids; a ratio of 1: 2 is optimal. Of this, more than a third of the fat consumed should consist of monounsaturated fatty acids, preferably oleic acid. The polyunsaturated fatty acids should contain as many omega-3 fatty acids as possible.

What are unsaturated fatty acids?

Fatty acids consist of chains of up to 26 carbon atoms that are chemically linked by single or double bonds. If there are one or more double bonds, one speaks of monounsaturated or polyunsaturated fatty acids, otherwise of saturated. Some important omega-3 fatty acids and omega-6 fatty acids are - similar to vitamins - essential nutrients: The human body needs them for life, but cannot produce them itself; it can only be obtained from food.

Which fat sources are particularly healthy and why?

The “good” fats include fish oil and vegetable oils from rapeseed, olives, linseed, algae or echium. Because all of these oils contain a high proportion of omega-3 fatty acids or are rich in oleic acid. In contrast, omega-6 fatty acids predominate in animal fats, but also in sunflower or corn oil. Our body produces hormone-like substances, the eicosanoids, from the long-chain omega-6 and omega-3 fatty acids. The eicosanoids from omega-3 fatty acids reduce the risk of cardiovascular diseases considerably through their effect on the blood vessels.

How could one stimulate the consumption of these healthy oils?

This is exactly what we checked with the Allipids project funded by the Federal Ministry of Education and Research (BMBF). We didn't want to bring new foods onto the market that no one might want to buy, precisely because they are not known. Instead, we took common foods - rolls, sausages, dairy products, snacks, and various sweet or savory spreads - and enriched them with oils that are high in omega-3 fatty acids. These products have been manufactured by our industrial partners. The problem with this is that the oils taste a bit fishy and go rancid quickly. The challenge now was to eliminate this annoying taste.

How did you solve the problem?

Our partners from the Institute for Agricultural and Urban Ecological Projects at the Humboldt University in Berlin and from the Karlsruhe Institute of Technology have achieved this. You have developed different variants to produce emulsions. The fat is encapsulated in small droplets. This has several advantages: On the one hand, it makes it tasteless and can be easily dissolved in water. That means you can mix it into drinks without tasting anything. In addition, the employees of Herbstreith & Fox have made sure that the emulsions remain stable and therefore storable. With these special emulsions, oils that would otherwise be avoided because of their taste can be processed in any food.

What did you do with these fortified foods?

First, we wanted to find out whether the human body can convert the vegetable and short-chain omega-3 fatty acids from our fortified products into long-chain fatty acids. Because the long-chain fatty acids protect our body. We selected volunteers who had slightly elevated blood lipids. For three months they were given our foods fortified with precisely measured amounts of linseed oil or echium oil or microalgae powder every day for three months. Before and after this time we measured all important blood lipid values. There was of course a control group for comparison.

The omega-3 and omega-6 fatty acids serve as precursors for messenger substances and tissue hormones. While the omega-3 fatty acids tend to contribute to the production of anti-inflammatory fatty hormones, the omega-6 fatty acids often serve as precursors for the body's own synthesis of inflammatory fatty hormones. In order to keep the right balance here, it is not so much a question of the absolute amount, but rather of an optimal ratio of the omega-3 and omega-6 fatty acids consumed. It should be around 1: 5.

What did the omega-3 foods do?

Daily consumption of foods fortified with linseed oil or echium oil led to a significant increase in long-chain omega-3 fatty acids in the blood. The results show that these two vegetable oils represent an alternative to the consumption of fish or fish oils. In addition, foods fortified with sunflower, linseed and microalgae oil improved blood lipid levels. In a second study, we then examined the effect of omega-3 fatty acids on rheumatic diseases. Rheumatism is a classic inflammatory disease; The best way to measure rheumatism is to what extent a changed composition of food influences important inflammatory parameters in the blood and actually leads to changes in quality of life. And the people who suffer from rheumatism often also have cardiovascular diseases. This gives us a model for both cardiovascular diseases and inflammation. The most important finding of this study was: The study participants really felt better after the time they ate foods fortified with omega-3 fatty acids. The joints were less stiff and the measurable signs of inflammation decreased.

What is your advice to people who suffer from rheumatism?

A spoonful of linseed oil for breakfast every morning. Or flaxseed in the yoghurt, but it has to be squashed or the grains have to be broken open, otherwise there is no point. With our support, a dairy has launched a yoghurt enriched with omega-3 fatty acids, called omeghurt. Anyone who suffers from rheumatism should consume omega-3 fatty acids that are as long-chain as possible, for three reasons: They reduce inflammation; because from the omega-3 fatty acids the anti-inflammatory fatty hormones can be formed. They also widen the blood vessels and thus reduce the risk of thrombosis. And they lower blood lipid levels. All of this has a positive effect on the quality of life of rheumatism sufferers.

What do you recommend to healthy people?

They too should pay attention to the fats and oils they consume. It's not enough to eat as many unsaturated fatty acids as possible - it could easily be the wrong ones. Those who only use sunflower or safflower oil are consuming too many omega-6 fatty acids. In the long run, this can even promote inflammation. Linseed oil, rapeseed oil, but also olive oil are always healthier, have anti-inflammatory effects and therefore reduce the risk of arteriosclerosis and other diseases.