Compliance with dietary guidelines affects capillary recruitment in healthy middle-aged men and women.

PURPOSE: Healthy microcirculation is important to maintain the health of tissues and organs, most notably the heart, kidney and retina. Single components of the diet such as salt, lipids and polyphenols may influence microcirculation, but the effects of dietary patterns that are consistent with current dietary guidelines are uncertain. It was hypothesized that compliance to UK dietary guidelines would have a favourable effect on skin capillary density/recruitment compared with a traditional British diet (control diet). METHODS: A 12-week randomized controlled trial in men and women aged 40-70 years was used to test whether skin microcirculation, measured by skin video-capillaroscopy on the dorsum of the finger, influenced functional capillary density (number of capillaries perfused under basal conditions), structural capillary density (number of anatomical capillaries perfused during finger cuff inflation) and capillary recruitment (percentage difference between structural and functional capillary density). RESULTS: Microvascular measures were available for 137 subjects out of the 165 participants randomized to treatment. There was evidence of compliance to the dietary intervention, and participants randomized to follow dietary guidelines showed significant falls in resting supine systolic, diastolic and mean arterial pressure of 3.5, 2.6 and 2.9 mmHg compared to the control diet. There was no evidence of differences in capillary density, but capillary recruitment was 3.5 % (95 % CI 0.2, 6.9) greater (P = 0.04) on dietary guidelines compared with control. CONCLUSIONS: Adherence to dietary guidelines may help maintain a healthy microcirculation in middle-aged men and women. This study is registered at www.isrctn.com as ISRCTN92382106.

Modulation of postprandial lipaemia by a single meal containing a commonly consumed interesterified palmitic acid-rich fat blend compared to a non-interesterified equivalent.

PURPOSE: Interesterification of palm stearin and palm kernal (PSt/PK) is widely used by the food industry to create fats with desirable functional characteristics for applications in spreads and bakery products, negating the need for trans fatty acids. Previous studies have reported reduced postprandial lipaemia, an independent risk factor for CVD, following interesterified (IE) palmitic and stearic acid-rich fats that are not currently widely used by the food industry. The current study investigates the effect of the most commonly consumed PSt/PK IE blend on postprandial lipaemia. METHODS: A randomised, controlled, crossover (1 week washout) double-blind design study (n = 12 healthy males, 18-45 years), compared the postprandial (0-4 h) effects of meals containing 50 g fat [PSt/PK (80:20); IE vs. non-IE] on changes in plasma triacylglycerol (TAG), glucose, glucose-dependent insulinotropic polypeptide (GIP), peptide YY (PYY), insulin, gastric emptying (paracetamol concentrations) and satiety (visual analogue scales). RESULTS: The postprandial increase in plasma TAG was higher following the IE PSt/PK versus the non-IE PSt/PK, with a 51 % greater incremental area under the curve [mean difference with 95 % CI 41 (23, 58) mmol/L min P = 0.001]. The pattern of lipaemia was different between meals; at 4-h plasma TAG concentrations declined following the IE fat but continued to rise following the non-IE fat. Insulin, glucose, paracetamol, PYY and GIP concentrations increased significantly after the test meals (time effect; P < 0.001 for all), but did not differ between test meals. Feelings of fullness were higher following the non-IE PSt/PK meal (diet effect; P = 0.034). No other significant differences were noted. CONCLUSIONS: Interesterification of PSt/PK increases early phase postprandial lipaemia (0-4 h); however, further investigation during the late postprandial phase (4-8 h) is warranted to determine the rate of return to baseline values. TRIAL REGISTRATION NUMBER: Clinicaltrials.gov as NCT02365987.

Acute effects of pomegranate extract on postprandial lipaemia, vascular function and blood pressure.

We investigated whether a test drink enriched in pomegranate polyphenols, consumed with a high-fat meal, can reduce postprandial lipaemia and improve vascular function and blood pressure compared to placebo. Nineteen young, healthy men completed a randomized, controlled crossover trial. The active drink (containing a pomegranate extract) was consumed during a high-fat meal (ET-DUR) or 15 min before (ET-PRE), and the placebo drink (no pomegranate extract) was consumed during the high-fat meal (CONTROL). Postprandial lipaemia was assessed by venous plasma TAG 0-2 h, and capillary plasma TAG 0-4 h. Blood pressure and digital volume pulse, to measure reflection index (DVP-RI) and stiffness index (DVP-SI), were monitored at baseline, 2 and 4 h. There was no inhibition of postprandial lipaemia by the active drink compared to CONTROL. ET-PRE caused a greater increase in the venous plasma TAG at 2 h compared to CONTROL and ET-DUR (treatment effect P = 0.001). The incremental area under the curve 0-4 h for capillary plasma TAG was not significantly different between treatments. Systolic blood pressure (SBP) increased in the ET-PRE and ET-DUR groups to a lesser extent than the CONTROL group (treatment effect P = 0.041). There were no treatment effects for DVP-RI, DVP-SI or diastolic blood pressure. In conclusion, the consumption of a single drink containing ET-rich pomegranate extract did not decrease postprandial plasma TAG concentrations, but suppressed the postprandial increase in SBP following the high-fat meal.