Introduction
The metabolic syndrome (MetS) is a cluster of disturbances including central adiposity, dyslipidemia, hypertension, and hyperglycemia. The prevalence of MetS is increasing and is estimated to affect 34% of the adult population, including nearly 50% of males and 57% of females over age 60. The risk of MetS is potentially modifiable with changes in the dietary fatty acid composition. This study seeks to determine the relationships between dietary, plasma, and adipose fatty acid and the components of MetS.
Methods
We conducted a cross-sectional study of 142 healthy older adults from Ohio aged 60-88, examining fat quality as measured by 7-day weighed food record (FR), diet history questionnaire (DHQ), plasma fatty acid composition, and adipose fatty acid composition. We then evaluated how these measurements relate to various components of MetS.
Results
Dietary saturated fat, monounsaturated fat, and cholesterol, as reported in the DHQ, predicted MetS diagnosis. Dietary monounsaturated fat as reported on the DHQ and n-3 fatty acids ALA, EPA, and DHA, as reported on the FR, were directly related to the number of features of MetS. Increased levels of plasma 16:0, 16:3n4, 18:1n9, and 20:1n9 were predictive of MetS. Plasma saturated and monounsaturated fatty acids were positively correlated, while plasma polyunsaturated fatty acids were negatively correlated, with triglyceride levels. Plasma ratios of 16:1 to 16:0 and 18:1 to 18:0 were positively correlated with triglyceride levels. The ratio of plasma 18:1 to 18:0 was also negatively correlated to HDL levels. Adipose 16:1n7 and 18:4n3 were decreased in subjects with increasing numbers of MetS features. Adipose 16:0 was correlated with each feature of MetS.
Conclusions
Dietary, plasma, and adipose fatty acid composition were shown to have relationships to components of metabolic syndrome in healthy older adults. Specifically, we have shown a relationship between n-3 fatty acid consumption and the presence of MetS components, suggesting a potential role for increased n-3 consumption and the reduction of MetS prevalence.