Acute effect of a single high-fat meal on forearm blood flow, blood pressure and heart rate in healthy male Asians and Caucasians: a pilot study

Abstract

Research has shown that ingestion of a single high-fat (HF) meal causes postprandial lipemia and produces a reduced brachial artery blood flow response to vascular occlusion in Caucasians. However, the forearm BF response to occlusion in Caucasian and Asian populations after a single HF meal has not been compared. Eleven healthy male Asians, mean age 26.4 (+/- 4.2) years, height 174.2 (+/- 7.4) cm, and weight 73.8 (+/- 5.7) kg and eight Caucasians, mean age 26.8 (+/- 4.6) years, height 182.9 (+/- 5.9) cm, and weight 82.8 (+/- 4.8) kg were studied. A randomized cross-over study design was used with a HF (50.1 g total fat) or low-fat (LF) (5.1 g total fat) test meal 1 week apart. Forearm blood flow was measured over a 2-minute period following a 4-minute occlusion (FBFO) at 2 and 4 hours following ingestion of a test meal. This study found that FBFO was significantly attenuated in Asians (19.3%; p = 0.09) compared to Caucasians after the ingestion of a HF meal. When comparing LF vs. HF meals in Asians, the FBFO were 336.9 ml/100 ml tissue/ minute and 240.8 ml/100 ml tissue/minute, respectively (p = 0.02), whereas in Caucasians, the FBFO were 344.8 ml/100 ml tissue/minute and 287.4 ml/100 ml tissue/minute, respectively. It appears Asians have a more sensitive response to a single HF meal which may be explained, in part, by genotypic variation. These findings suggest that a single HF meal may contribute to the detrimental effects on vascular health in Asian males and raises speculation regarding the cumulative impact of a chronic HF diet in this population.

Figures

Fig 1

Blood flow at rest and after 4-minutes of vascular occlusion. This was recorded every 12 seconds for 2 minutes following the release of the arterial occlusion cuff on the brachial artery. Peak blood flow after occlusion was measured at 3 seconds post-occlusion. Blood flow is expressed in ml/100 ml forearm tissue/minute.

Fig 2

Comparison of Asians to Caucasians before, 2-hours and 4-hours following ingestion of a single HF meal in total blood flow response to anoxia over 2 minutes (excess FBFO) (A); peak blood flow after occlusion (peak FBFO) (B); arterial resistance (C); and cardiac work index (D). The excess FBFO was calculated from the area under the exponential curve (2-minutes post-occlusion) subtracted by the resting blood flow.

Fig 3

Comparing the change in total blood flow response to anoxia over 2 minutes (excess FBFO) and peak blood flow after occlusion (peak FBFO) at 2 hours following the ingestion of a HF vs LF meal in healthy Asians.