Blood biomarkers of trans-fatty acid intake among Nigerian adults in the Federal Capital Territory: a cross-sectional study

Intake of trans-fatty acids (TFAs) is an established risk factor for cardiovascular disease. In April 2023, Nigeria passed regulations limiting TFA content in foods, fats, and oils, but the current level of TFA exposure in the Nigerian population is unknown. To quantify trans-fatty acid (TFA) biomarkers in dried blood spots from Nigerian adults in the Federal Capital Territory before policy enforcement, establish baseline levels for future evaluations, assess subgroup variations by demographic and socioeconomic factors, and compare TFA levels with data from 30 countries worldwide. We used gas chromatography to measure TFA content in dried blood spots from adults participating in a cross-sectional household survey using a representative sampling frame. Individual TFA (t-16:1, t-18:1, and t- 18:2) and their total were expressed as percentage of total fatty acids. We assessed differences in TFA levels between subgroups based on sex, age, body mass index (BMI), education, income, and local government area using multivariable-adjusted linear regression models. Mean TFA levels were compared with samples from individuals in 30 countries. In 213 adults (62% females; mean age: 36 y, mean BMI: 25.9 kg/m2), the mean TFA level in dried blood spots was 0.61% of total fatty acids (range: 0.23%–1.31%). In multivariable-adjusted models, TFA levels were higher in younger adults {