Postprandial Lipid Metabolism in Normolipidemic Subjects and Patients with Mild to Moderate Hypertriglyceridemia: Effects of Test Meals Containing Saturated Fatty Acids, Mono-Unsaturated Fatty Acids, or Medium-Chain Fatty Acids

Abstract

Fasting and postprandial hypertriglyceridemia are causal risk factors for atherosclerosis. The prevalence of hypertriglyceridemia is approximately 25-30% and most hypertriglyceridemic patients suffer from mild to moderate hypertriglyceridemia. Data regarding dietary interventions on postprandial triglyceride metabolism of mildly to moderately hypertriglyceridemic patients is, however, sparse. In a randomized controlled trial, eight mildly hypertriglyceridemic patients and five healthy, normolipidemic controls received three separate standardized fat-meals containing either saturated fatty acids (SFA), mono-unsaturated fatty acids (MUFA), or medium-chain fatty acids (MCFA) in a randomized order. Fasting and postprandial lipid parameters were determined over a 10 h period and the (incremental) area under the curve (AUC/iAUC) for plasma triglycerides and other parameters were determined. MCFA do not lead to a significant elevation of postprandial total plasma triglycerides and other triglyceride parameters, while both SFA (patients: p = 0.003, controls: p = 0.03 compared to MCFA) and MUFA (patients: p = 0.001; controls: p = 0.14 compared to MCFA) do lead to such an increase. Patients experienced a significantly more pronounced increase of plasma triglycerides than controls (SFA: patients iAUC = 1006 mg*h/dL, controls iAUC = 247 mg*h/dL, p = 0.02; MUFA: patients iAUC = 962 mg*h/dL, controls iAUC = 248 mg*h/dL, p = 0.05). Replacing SFA with MCFA may be a treatment option for mildly to moderately hypertriglyceridemic patients as it prevents postprandial hypertriglyceridemia.

Keywords: MCT; fatty acids; hyperlipidemia; hypertriglyceridemia; medium chain triglycerides.

Figure 1

Mean total triglyceride levels (mg/dL) over time (h) (A) for five normolipidemic subjects and (B) for eight mildly to moderately hypertriglyceridemic patients. SFA: saturated fatty acids; MUFA: mono-unsaturated fatty acids; MCFA: medium-chain fatty acids. Shown are means and standard error of mean. Please note difference in scale on y-axis.

Figure 2

Mean incremental area under the curve (mg*h /dL) for total triglycerides (A) for five normolipidemic subjects and (B) for eight mildly to moderately hypertriglyceridemic patients. SFA: saturated fatty acids; MUFA: mono-unsaturated fatty acids; MCFA: medium-chain fatty acids. Shown are means and standard error of mean. Please note difference in scale on y-axis.

Figure 3

Variability in fasting triglyceride levels for five normolipidemic controls (subjects 1–5) and eight mildly to moderately hypertriglyceridemic patients (6–13) during screening and before each of the different test meals. SFA, saturated fatty acids; MCFA, medium chain fatty acids; MUFA, monounsaturated fatty acids.