What are fatty acids?
Fatty acids are components of the fats found in food. Depending on their chemical structure, fatty acids can be divided into different groups: saturated, monounsaturated, and polyunsaturated fatty acids. Polyunsaturated fatty acids include omega-3, omega-6, and omega-9 fatty acids. Fatty animal-based foods, such as butter, cheese, meat, and sausages, contain mainly saturated and monounsaturated fatty acids (see Table 1), while coconut oil and palm oil consist mainly of saturated fatty acids, and vegetable oils such as olive and rapeseed are rich in monounsaturated fatty acids (especially oleic acid, an omega-9 fatty acid). Polyunsaturated fatty acids are mainly found in industrially produced vegetable oils.Omega-3 and omega-6 fatty acids need to be supplied through food
Plant-based foods are good sources of the essential fatty acids, linoleic acid and alpha-linolenic acid. Linseed oil has the highest content of alpha-linolenic acid (see Table 2), while other sources include rapeseed, walnut, and hemp oil. Linoleic acid is found in walnuts, peanuts, and tofu, as well as in sunflower, thistle, and wheat-germ oil. Plant-based sources of the omega-3 fatty acids EPA and DHA include certain microalgae, which are now also available as food supplements. EPA and DHA accumulate in fish via these microalgae, which is why cold-water fish have such high levels of these omega-3 fatty acids.| Food | alpha-Linolenic acid | Linolenic acid | Oleic acid |
| g/100 g | |||
| Plant food | |||
| Walnuts | 8 | 34 | 11 |
| Peanuts | 0,5 | 14 | 22 |
| Avocado | 0,2 | 2 | 14 |
| Hazelnuts | 0,1 | 8 | 46 |
| Plant oils | |||
| Linseed oil | 54 | 14 | 18 |
| Hemp oil | 18 | 15 | 11 |
| English Walnut oil | 13 | 55 | 18 |
| Rapeseed oil | 9 | 22 | 53 |
| Safflower oil | 0,5 | 75 | 10 |
| Extra-virgin Olive oil | 1 | 8 | 69 |
| Soya oil | 8 | 53 | 19 |
| Wheat germ oil | 8 | 56 | 14 |
| Corn germ oil | 1 | 55 | 26 |
| Sunflower oil | 0,5 | 63 | 20 |
Table 2: Unsaturated fatty acid content in selected foods
Linseed oil and linseed
Linseed oil should not be heated and is thus only suitable for cold cooking. After opening, linseed oil should be stored in the refrigerator and consumed quickly to prevent the degrading of nutrients. Due to its low melting point, linseed oil can also be stored in the freezer for several weeks. Linseeds themselves also contain a lot of omega-3, in the form of α-linolenic acid. However, since they are very small and usually insufficiently chewed, most of the nutritional components are inaccessible to the human digestive system. To access their omega-3 fatty acids, linseeds should be crushed or ground shortly before consumption. They can then be mixed into salads or muesli, for example.Chia seeds – an alternative source of omega-3 fatty acids
Chia seeds have a high nutrient density, which means that they can be a useful addition to one’s diet, even in small doses (for example, by adding to muesli or as a gelling agent or egg alternative for vegan pastries). They contain high amounts of calcium, fibre, and polyunsaturated essential fatty acids, as well as a good amount of protein. Chia seeds provide an average of 19 grams of omega-3 fatty acids and 7 grams of omega-6 fatty acids per 100 grams. Accordingly, chia seeds have an advantageous ratio of omega-6 to omega-3 fatty acids, as they are particularly rich in α-linolenic acid. However, according to the EU’s Novel Food Regulation, daily intake of chia seeds should not exceed 15 grams (about 1.5 tablespoons per day), since chia seeds can have both laxative and constipation effects at higher levels of consumption.Omega-3 fatty acid requirements
The recommended intake for adults is 2.5% of daily energy intake for linoleic acid (about 6-8 g) and 0.5% for α-linolenic acid (about 1.5 g). A typical Western diet has an imbalanced ratio with far too many omega-6 fatty acids consumed in relation to omega-3 fatty acids. Because of their importance for brain development, infants and young children have a higher need for polyunsaturated fatty acids, especially DHA. If the mother has a good supply of all essential fatty acids, as well as of DHA, it is possible to meet the child’s needs through breast milk.Omega-3 fatty acid deficiency
An insufficient supply of omega-3 fatty acids increases the risk of cardiovascular diseases and inflammatory diseases, as well as neurological disorders such as schizophrenia, Alzheimer’s disease, depression, and attention deficit hyperactivity disorder (ADHD).Omega-3 fatty acid supply in veggies
The recommended intake of omega-3 fatty acids is the same for vegans, vegetarians, and meat eaters. However, much higher amounts of omega-6 fatty acids are consumed through plant-based foods, so the ratio of omega-6 to omega-3 fatty acids is much higher for those on a plant-based diet compared to omnivores. Vegans are thus the furthest away from the recommended ratio of 2-4:1, because of the low intake of EPA and DHA. Our body doesn’t convert α-linolenic acid into EPA and DHA very well, and it’s even harder when there are a lot of omega-6 fatty acids in our diet. This means that people following a plant-based diet often have low levels of EPA and DHA. However, in the extensive EPIC-Norfolk study of the links between health and diet, there were no major differences in blood levels of EPA and DHA between people eating fish, meat, vegan or vegetarian diets – although intakes steadily decreased in that order. It is possible that the rate of conversion of α-linolenic acid to EPA and DHA increases when only small amounts of EPA and DHA are consumed in the diet. Regardless, it is unclear whether potentially lower blood levels of EPA and DHA in vegan and vegetarian people are relevant to neurological or cardiovascular diseases and other health aspects. The research is still limited, especially for vegans, and long-term studies are needed. People following a vegan or vegetarian diet can improve their supply of omega-3 fatty acids by increasing their intake of α-linolenic acid. At the same time, the consumption of linoleic acid should be reduced. For example, eating 30 grams of English walnuts or one tablespoon of linseed oil per day will provide about 2-4 grams of α-linolenic acid.Support DHA intake with microalgae oils
The supply of DHA can be improved by consuming microalgae oils, for example, or DHA-enriched linseed oil. This is recommended for people on a vegan diet who are pregnant or breastfeeding, in order to ensure an adequate supply of DHA for the child. Vegetable oils that are rich in monounsaturated fatty acids, such as extra-virgin olive oil and rapeseed oil, should constitute the main component of daily fat intake. Like polyunsaturated linoleic acid, they lower LDL cholesterol levels and thus have protective effects on the cardiovascular system. In order to optimise the supply of omega-3 fatty acids, the intake of α-linolenic acid should be increased and that of linoleic acid (e.g. sunflower, safflower, and maize-germ oil) reduced. Linseed oil, which contains both a lot of α-linolenic acid and just a little linoleic acid, should therefore be consumed daily.Conclusion
- A good supply of omega-3 fatty acids can reduce the risk of cardiovascular disease, inflammatory diseases, and neurological disorders.
- People following vegetarian or vegan diets can ensure a good supply of omega-3 fatty acids by regularly consuming vegetable oils that are rich in α-linolenic acid, especially linseed oil and rapeseed oil, along with ground linseed and English walnuts.
- For pregnant and breastfeeding parents, a direct supply of DHA, for example via microalgae oils, is recommended.
| Name | Main source |
| Saturated fatty acids | |
| Palmitic acid, stearic acid, etc. | Butter, cream, cheese, sausages, meat, lard, tallow, coconut fat, palm oil |
| Monounsaturated fatty acids | |
| Oleic acid | Olive oil, rapeseed oil, hazelnuts, avocado |
| Polyunsaturated fatty acids | |
| Omega 6 fatty acids | |
| Linoleic acid | Safflower oil, sunflower oil, wheat germ oil, corn germ oil, soya-bean oil, sesame oil, chia seeds |
| Arachidonic acid | Lard, pork liver, egg yolk, tuna, liver sausage, pork, beef, chicken, camembert, salmon, mackerel |
| Omega 3 fatty acids | |
| alpha-linolenic acid (ALA) | Linseed oil, hemp oil, walnut oil, rapeseed oil, chia seeds |
| Eicosapentaenoic acid (EPA) | Herring (Atlantic, Baltic Sea), tuna, sprat, salmon |
| Docosahexaenoic acid (DHA) | Tuna, sprat, salmon, herring (Baltic Sea), mackerel, microalgae (Schizochytrium sp. and Ulkenia sp.) |
Table 1: Overview of the most important fatty acids in foods
How omega-3 fatty acids work
Polyunsaturated fatty acids such as omega-6 and omega-3 are a vital component of cell membranes in the human body. They are present in particularly high concentrations in brain and nerve cells, and play an important role as components of the eye’s retina. They are also important for the development of the brain and eyes in infants and young children. Omega-6 and omega-3 fatty acids are the base substances for the formation of eicosanoids – hormone-like compounds that send signals such as inflammation to the body. A high intake of arachidonic acid, one of the omega-6 acids, will promote inflammation. In contrast, omega-3 fatty acids form anti-inflammatory substances. These dilate blood vessels, counteract high blood pressure, and improve the flow properties of blood and the concentrations of the various blood fats. Omega-3 fatty acids thus reduce the risk of cardiovascular diseases, and also have a positive influence on rheumatic diseases, since they curb inflammatory processes.Where do we get omega-3 fatty acids from?
Plant-based foods are good sources of the essential fatty acids, linoleic acid and alpha-linolenic acid. Linseed oil has the highest content of alpha-linolenic acid (see Table 2), while other sources include rapeseed, walnut, and hemp oil. Linoleic acid is found in walnuts, peanuts, and tofu, as well as in sunflower, thistle, and wheat-germ oil. Plant-based sources of the omega-3 fatty acids EPA and DHA include certain microalgae, which are now also available as food supplements. EPA and DHA accumulate in fish via these microalgae, which is why cold-water fish have such high levels of these omega-3 fatty acids.| Food | alpha-Linolenic acid | Linolenic acid | Oleic acid |
| g/100 g | |||
| Plant food | |||
| Walnuts | 8 | 34 | 11 |
| Peanuts | 0,5 | 14 | 22 |
| Avocado | 0,2 | 2 | 14 |
| Hazelnuts | 0,1 | 8 | 46 |
| Plant oils | |||
| Linseed oil | 54 | 14 | 18 |
| Hemp oil | 18 | 15 | 11 |
| English Walnut oil | 13 | 55 | 18 |
| Rapeseed oil | 9 | 22 | 53 |
| Safflower oil | 0,5 | 75 | 10 |
| Extra-virgin Olive oil | 1 | 8 | 69 |
| Soya oil | 8 | 53 | 19 |
| Wheat germ oil | 8 | 56 | 14 |
| Corn germ oil | 1 | 55 | 26 |
| Sunflower oil | 0,5 | 63 | 20 |
Table 2: Unsaturated fatty acid content in selected foods
Linseed oil and linseed
Linseed oil should not be heated and is thus only suitable for cold cooking. After opening, linseed oil should be stored in the refrigerator and consumed quickly to prevent the degrading of nutrients. Due to its low melting point, linseed oil can also be stored in the freezer for several weeks. Linseeds themselves also contain a lot of omega-3, in the form of α-linolenic acid. However, since they are very small and usually insufficiently chewed, most of the nutritional components are inaccessible to the human digestive system. To access their omega-3 fatty acids, linseeds should be crushed or ground shortly before consumption. They can then be mixed into salads or muesli, for example.Chia seeds – an alternative source of omega-3 fatty acids
Chia seeds have a high nutrient density, which means that they can be a useful addition to one’s diet, even in small doses (for example, by adding to muesli or as a gelling agent or egg alternative for vegan pastries). They contain high amounts of calcium, fibre, and polyunsaturated essential fatty acids, as well as a good amount of protein. Chia seeds provide an average of 19 grams of omega-3 fatty acids and 7 grams of omega-6 fatty acids per 100 grams. Accordingly, chia seeds have an advantageous ratio of omega-6 to omega-3 fatty acids, as they are particularly rich in α-linolenic acid. However, according to the EU’s Novel Food Regulation, daily intake of chia seeds should not exceed 15 grams (about 1.5 tablespoons per day), since chia seeds can have both laxative and constipation effects at higher levels of consumption.Omega-3 fatty acid requirements
The recommended intake for adults is 2.5% of daily energy intake for linoleic acid (about 6-8 g) and 0.5% for α-linolenic acid (about 1.5 g). A typical Western diet has an imbalanced ratio with far too many omega-6 fatty acids consumed in relation to omega-3 fatty acids. Because of their importance for brain development, infants and young children have a higher need for polyunsaturated fatty acids, especially DHA. If the mother has a good supply of all essential fatty acids, as well as of DHA, it is possible to meet the child’s needs through breast milk.Omega-3 fatty acid deficiency
An insufficient supply of omega-3 fatty acids increases the risk of cardiovascular diseases and inflammatory diseases, as well as neurological disorders such as schizophrenia, Alzheimer’s disease, depression, and attention deficit hyperactivity disorder (ADHD).Omega-3 fatty acid supply in veggies
The recommended intake of omega-3 fatty acids is the same for vegans, vegetarians, and meat eaters. However, much higher amounts of omega-6 fatty acids are consumed through plant-based foods, so the ratio of omega-6 to omega-3 fatty acids is much higher for those on a plant-based diet compared to omnivores. Vegans are thus the furthest away from the recommended ratio of 2-4:1, because of the low intake of EPA and DHA. Our body doesn’t convert α-linolenic acid into EPA and DHA very well, and it’s even harder when there are a lot of omega-6 fatty acids in our diet. This means that people following a plant-based diet often have low levels of EPA and DHA. However, in the extensive EPIC-Norfolk study of the links between health and diet, there were no major differences in blood levels of EPA and DHA between people eating fish, meat, vegan or vegetarian diets – although intakes steadily decreased in that order. It is possible that the rate of conversion of α-linolenic acid to EPA and DHA increases when only small amounts of EPA and DHA are consumed in the diet. Regardless, it is unclear whether potentially lower blood levels of EPA and DHA in vegan and vegetarian people are relevant to neurological or cardiovascular diseases and other health aspects. The research is still limited, especially for vegans, and long-term studies are needed. People following a vegan or vegetarian diet can improve their supply of omega-3 fatty acids by increasing their intake of α-linolenic acid. At the same time, the consumption of linoleic acid should be reduced. For example, eating 30 grams of English walnuts or one tablespoon of linseed oil per day will provide about 2-4 grams of α-linolenic acid.Support DHA intake with microalgae oils
The supply of DHA can be improved by consuming microalgae oils, for example, or DHA-enriched linseed oil. This is recommended for people on a vegan diet who are pregnant or breastfeeding, in order to ensure an adequate supply of DHA for the child. Vegetable oils that are rich in monounsaturated fatty acids, such as extra-virgin olive oil and rapeseed oil, should constitute the main component of daily fat intake. Like polyunsaturated linoleic acid, they lower LDL cholesterol levels and thus have protective effects on the cardiovascular system. In order to optimise the supply of omega-3 fatty acids, the intake of α-linolenic acid should be increased and that of linoleic acid (e.g. sunflower, safflower, and maize-germ oil) reduced. Linseed oil, which contains both a lot of α-linolenic acid and just a little linoleic acid, should therefore be consumed daily.Conclusion
- A good supply of omega-3 fatty acids can reduce the risk of cardiovascular disease, inflammatory diseases, and neurological disorders.
- People following vegetarian or vegan diets can ensure a good supply of omega-3 fatty acids by regularly consuming vegetable oils that are rich in α-linolenic acid, especially linseed oil and rapeseed oil, along with ground linseed and English walnuts.
- For pregnant and breastfeeding parents, a direct supply of DHA, for example via microalgae oils, is recommended.
