Saturated Fatty Acids
Saturated fatty acids can be either dietary components or synthesized by the body from carbohydrates. Therefore, they do not necessarily need to be obtained through diet.
Chemical Structure
Fatty acids generally consist of carbon, oxygen, and hydrogen atoms arranged in a carbon-hydrogen chain. In comparison to mono- and polyunsaturated fatty acids, saturated fatty acids have no double bond(s) between adjacent carbon atoms. The carbon-hydrogen chain is "saturated" with hydrogen atoms, maximally and completely. Each carbon atom forms four covalent single bonds with its neighboring atoms.
Saturated fatty acids also differ in the number of carbon atoms they contain (see the next section).
Saturated Fatty Acids of Plant Origin
There are numerous naturally occurring saturated fatty acids. Here is a selection of saturated fatty acids found in plant-based foods:
Saturated Fatty Acids | Carbon Atoms : Double Bonds |
---|---|
Caprylic Acid Caprylic Acid Foods |
8:0 |
Capric Acid Capric Acid Foods |
10:0 |
Lauric Acid Lauric Acid Foods |
12:0 |
Myristic Acid Myristic Acid Foods |
14:0 |
Pentadecanoic Acid | 15:0 |
Palmitic Acid Palmitic Acid Foods |
16:0 |
Margaric Acid | 17:0 |
Stearic Acid Stearic Acid Foods |
18:0 |
Arachidic Acid Arachidic Acid Foods |
20:0 |
Behenic Acid Behenic Acid Foods |
22:0 |
Lignoceric Acid | 24:0 |
Caprylic Acid, Capric Acid, and Lauric Acid are medium-chain fatty acids that belong to the group of medium-chain triglycerides (MCTs). Medium-chain triglycerides contain fatty acids in their structure that have carbon chain lengths ranging from 6 to 12 carbon atoms. Long-chain triglycerides have fatty acids in their structure with carbon chain lengths of 14 to 24.
At room temperature, fats like coconut oil with a high content of saturated fatty acids and medium-chain triglycerides are solid.
Functions in the Body
Saturated fatty acids are needed as components of cell membranes and for hormone production 1.
In addition, they serve as a very good source of energy for the body. When the body is not supplied with enough energy in the form of carbohydrates, saturated fatty acids are preferentially utilized 2.
Intake Recommendations
There are no precise guidelines for the recommended intake of saturated fats. Nevertheless, consumption should not exceed 10% of the daily calorie requirement's energy 3. The American Heart Association has lowered its intake recommendations from 7% to now only 5 to 6% of daily energy from saturated fats since 2006 4 5.
The following values result from this for the daily intake of saturated fatty acids:
Caloric Requirement | Upper Limit of Saturated Fatty Acid Intake - at 5 to 6% of daily energy needs | Upper Limit of Saturated Fatty Acid Intake - at 10% of daily energy needs |
---|---|---|
2,000 kcal | 10.8 to 12.9 g | 21.5 g |
2,200 kcal | 11.8 to 14.2 g | 23.7 g |
2,400 kcal | 12.9 to 15.5 g | 25.8 g |
2,600 kcal | 14 to 16.8 g | 28 g |
2,800 kcal | 15.1 to 18.1 g | 30.1 g |
3,000 kcal | 16.1 to 19.4 g | 32.3 g |
Carbohydrates turning into saturated fatty acids
If too many carbohydrates are consumed with the diet, the liver converts them into saturated fatty acids (initially into palmitic acid and then into palmitoleic acid) and stores them as fat tissue.
Do saturated fatty acids harm health? - Controversy
It is known that saturated fatty acids promote the formation of "bad" LDL cholesterol 6. It is also established since 2014 that an excess of saturated fatty acids promotes fat deposition in the liver and in the abdominal area (visceral fat) 7.
According to some research findings, it brings health benefits (reduced risk of heart disease, lower LDL cholesterol levels, and type 2 diabetes) when saturated fats are replaced with polyunsaturated fats. 8 9 10 11 12 13. According to study findings from 2015, a lower cholesterol level could be achieved by replacing fatty acids. 14.
Other study results show that replacing 5% of the energy intake from saturated fats with an equivalent energy intake of polyunsaturated fats, monounsaturated fatty acids, or carbohydrates from whole grains reduces the risk of coronary heart disease by 25%, 15%, and 9%, respectively. 15.
In studies, a 17% reduction in the risk of cardiovascular diseases was achieved by reducing daily energy intake from saturated fats. 16. Another study from 2015 revealed a greater risk of atherosclerotic vascular diseases associated with mortality in older women due to higher consumption of saturated fats. 17. Furthermore, the study found a strong positive correlation between saturated fats and LDL cholesterol. However, in this study, LDL cholesterol was not associated with higher mortality risk.
A highly regarded study summary from 2010 showed that there is no significant evidence of an increase in heart and cardiovascular diseases due to saturated fatty acids 18. Other scientists also found no sufficient evidence for a connection between heart diseases and saturated fatty acids in 2014 19. However, scientists from Harvard University doubt the results and consider them seriously misleading due to significant errors and omissions 20. In August 2015, another study summary was published, which also did not associate saturated fatty acids with overall mortality, cardiovascular diseases, heart diseases, stroke, or type 2 diabetes 21. So, we will have to wait and see what further research findings the scientists will provide.
Too many saturated fats increase the risk of breast cancer
Furthermore, according to a large study, there is a weak positive association between saturated fats and breast cancer risk. 22. This association was found to be stronger in postmenopausal women, according to the scientists. A more recent study by the researchers confirms these findings. Women with the highest intake of saturated fats (47.5g per day) statistically had a significantly increased risk of breast cancer compared to those with lower intake of saturated fats (15.4g per day) 23.
Occurrence
Saturated fatty acids are primarily used by the industry for the production of processed foods, as they are less susceptible to rancidity compared to unsaturated fatty acids. Therefore, they are predominantly found in processed foods such as fast food or sweets like chocolate. Vegan foods containing cocoa butter and palm oil also have higher amounts. Natural sources include nuts and seeds, the flesh of the coconut as well as the derived coconut oil. You can find the list of foods high in saturated fatty acids here.
Do vegans need to consider anything?
No. The vegan diet is rather low in saturated fatty acids 24 25. Compared to other dietary forms, the vegan diet significantly reduces the intake of saturated fatty acids. According to a Polish study, vegan diets account for 5.2%, ovo-lacto-vegetarian diets for 11.2%, and non-vegetarian diets for 11.9% of daily energy intake from saturated fatty acids 26. Vegans particularly have a favorable ratio of polyunsaturated fatty acids to saturated fatty acids, which appears to be beneficial for the risk of coronary heart disease 27.