Trans-unsaturated fatty acids (also known as trans-fatty acids or trans-fats)are unsaturated fatty acids that contain at least one double bond in the trans orientation between the carbon atoms that make up the hydrocarbon chain of the fatty acid. They are present in small amounts in some meat and dairy products. However, the bulk of trans-fats are likely obtained from margarine, shortening, fried fast food, packaged snacks, and baked food products. For commercial use, trans-fats are produced by adding hydrogen atoms to vegetable oil in a process called hydrogenation. They are used in processed foods to improve taste and increase shelf life.
Previous studies have shown that dietary intake of trans-fatty acids is linked to a rise in systemic inflammatory markers.1,2 Inflammatory markers are like a biological red flag; when we see inflammatory markers, we know that the body is trying to repair damage or is fighting off disease or infection through inflammation. However, these studies used food questionnaires and/or nutrient databases to estimate dietary trans-fat intake, which can be prone to error. A new study, which published its findings recently in the Journal of Nutrition and Metabolism, measured trans-fat levels in the blood serum and correlated this with the blood serum levels of two markers of systemic inflammation, hs-CRP and fibrinogen.3
The study used data collected by the US National Center for Health Statistics (NCHS) during the 1999-2000 period as part of its US National Health and Nutrition Examination Surveys. The serum levels of trans-9-hexadecenoic acid (palmitelaidic acid), trans-9-octadecenoic acid (elaidic acid), trans-11-octadecenoic acid (vaccenic acid), and trans-9-, trans-12-octadecadienoic acid (linolelaidic acid) were measured. Also measured were the serum levels of inflammatory markers hs-CRP and fibrinogen. Data from 5446 adults(2550 men and 2896 women) with a mean age of 47.1 years was analyzed.
Data analysis showed that the levels of both hs-CRP and fibrinogenin the serum increased with increasing levels of total trans-fats. When differences due to sex, race, education, marital status, body mass index, and smoking were taken into account during data analysis, the levels of trans-9-hexadecenoic acid, trans-11-octadecenoic acid, trans-9-octadecenoic acid were found to increase with serum hs-CR levels, whereas the levels of trans-9-hexadecenoic acid and trans-11-octadecenoic acid increased with an increase in fibrinogen levels.
These results confirm the findings of previous studies that report a link between dietary trans-fat intake and inflammatory marker levels. Studies have also noted that that the treatment of human endothelial cell cultures with trans-fats induces a pro-inflammatory response by activating a protein called nuclear factor-kappa B (NF-kB), which then activates the expression of the pro-inflammatory protein intercellular adhesion molecule-1 (ICAM-1).4Chronic inflammation has been noted as a mechanism underlying the development of type 2 diabetes and cardiovascular disease.5
Overall, these findings indicate that chronic inflammation can be reduced by reducing dietary trans-fat consumption.Start by reading nutrition labels on packaged foods and choosing those that have low or no trans-fats. Other steps could include using non-hydrogenated margarine instead of shortening for baking, cutting your consumption of deep-fried foods, and adopting a diet rich in whole grains, fruits, and vegetables.
Written by Usha B. Nair, Ph.D.
- Mozaffarian D, Pischon T, Hankinson SE, Rifai N, Joshipura K, Willett WC, Rimm EB. Dietary intake of trans fatty acids and systemic inflammation in women. Am J Clin Nutr. 2004 Apr;79(4):606-12. PubMed PMID: 15051604; PubMed Central PMCID: PMC1282449.
- Baer DJ, Judd JT, Clevidence BA, Tracy RP. Dietary fatty acids affect plasma markers of inflammation in healthy men fed controlled diets: a randomized crossover study. Am J Clin Nutr. 2004 Jun;79(6):969-73. PubMed PMID: 15159225.
- Mazidi M, Gao HK, Kengne AP. Inflammatory Markers Are Positively Associated with Serum trans-Fatty Acids in an Adult American Population. J Nutr Metab. 2017;2017:3848201. doi: 10.1155/2017/3848201. Epub 2017 Jul 11. PubMed PMID: 28781892; PubMed Central PMCID: PMC5525085.
- Harvey KA, Walker CL, Xu Z, Whitley P, Siddiqui RA. Trans fatty acids: induction of a pro-inflammatory phenotype in endothelial cells. Lipids. 2012 Jul;47(7):647-57. doi: 10.1007/s11745-012-3681-2. Epub 2012 Jun 9. PubMed PMID: 22684911.
- Welty FK, Alfaddagh A, Elajami TK. Targeting inflammation in metabolic syndrome. Transl Res. 2016 Jan;167(1):257-80. doi: 10.1016/j.trsl.2015.06.017. Epub 2015 Jul 3. Review. PubMed PMID: 26207884.