Impact of short-term dietary modification on postprandial oxidative stress

Twenty-two subjects (10 men and 12 women; aged 35 ± 3 years) completed a 21-day Daniel Fast. To induce oxidative stress, a milkshake (fat = 0.8 g·kg-1; carbohydrate = 1.0 g·kg-1; protein = 0.25 g·kg-1) was consumed by subjects on day one and day 22 in a rested and 12-hour fasted state. Before and at 2 and 4 h after consumption of the milkshake, heart rate (HR) and blood pressure were measured. Blood samples were also collected at these times and analyzed for TAG, malondialdehyde (MDA), hydrogen peroxide (H2O2), advanced oxidation protein products (AOPP), nitrate/nitrite (NOx), and Trolox Equivalent Antioxidant Capacity (TEAC).A time effect was noted for HR (p = 0.006), with values higher at 2 hr post intake of the milkshake as compared to pre intake (p < 0.05). Diastolic blood pressure was lower post fast as compared to pre fast (p = 0.02), and a trend for lower systolic blood pressure was noted (p = 0.07). Time effects were noted for TAG (p = 0.001), MDA (p < 0.0001), H2O2 (p < 0.0001), AOPP (p < 0.0001), and TEAC (p < 0.0001); all concentrations were higher at 2 h and 4 h post intake compared to pre intake, except for TEAC, which was lower at these times (p < 0.05). A condition effect was noted for NOx (p = 0.02), which was higher post fast as compared to pre fast. No pre/post fast × time interactions were noted (p > 0.05), with the area under the curve from pre to post fast reduced only slightly for TAG (11%), MDA (11%), H2O2 (8%), and AOPP (12%), with a 37% increase noted for NOx.Partaking in a 21-day Daniel Fast does not result in a statistically significant reduction in postprandial oxidative stress. It is possible that a longer time course of adherence to the Daniel Fast eating plan may be needed to observe significant findings.Modifying dietary intake in a manner that reduces kilocalorie ingestion and emphasizes the consumption of nutrient dense, plant-derived foods such as fruits, vegetables, whole grains, nuts and seeds [1-3] yields favorable health effect