Time-restricted feeding (TRF) is a form of intermittent fasting that involves having a longer daily fasting period. Preliminary studies report that TRF improves cardiometabolic health in rodents and humans. Here, we performed the first study to determine how TRF affects gene expression, circulating hormones, and diurnal patterns in cardiometabolic risk factors in humans. Eleven overweight adults participated in a 4-day randomized crossover study where they ate between 8 am and 2 pm (early TRF (eTRF)) and between 8 am and 8 pm (control schedule). Participants underwent continuous glucose monitoring, and blood was drawn to assess cardiometabolic risk factors, hormones, and gene expression in whole blood cells. Relative to the control schedule, eTRF decreased mean 24-hour glucose levels by 4 ± 1 mg/dl (p = 0.0003) and glycemic excursions by 12 ± 3 mg/dl (p = 0.001). In the morning before breakfast, eTRF increased ketones, cholesterol, and the expression of the stress response and aging gene SIRT1 and the autophagy gene LC3A (all p < 0.04), while in the evening, it tended to increase brain-derived neurotropic factor (BNDF; p = 0.10) and also increased the expression of MTOR (p = 0.007), a major nutrient-sensing protein that regulates cell growth. eTRF also altered the diurnal patterns in cortisol and the expression of several circadian clock genes (p < 0.05). eTRF improves 24-hour glucose levels, alters lipid metabolism and circadian clock gene expression, and may also increase autophagy and have anti-aging effects in humans.
Elevated serum uric acid (UA), a biomarker of renal insufficiency, is also an independent prognostic marker for morbidity in coronary artery disease (CAD) and poses serious health risks. This study reports the effect of almond consumption on UA in CAD patients. A randomized controlled clinical trial was conducted with three groups: no-intervention (NI), Pakistani almonds (PA) or American almonds (AA). Patients were recruited from the Cardiology Clinics, Aga Khan University Hospital. Two follow-ups were scheduled at week-6 and week-12. 150 patients were randomly divided in three groups (50 per group). NI was not given almonds, whereas the PA and AA were given Pakistani and American almond varieties (10 g/day), respectively; with instruction to soak overnight and eat before breakfast. Almonds supplementation significantly reduced (p < 0.05) serum UA among groups, and over time. At week-6, UA concentrations were -13 to -16 % less in PA and AA; at week-12 the concentrations were -14 to -18 % less, compared to NI. Systolic and diastolic blood pressure and body weights of the participants remained fairly constant among all the groups. Almonds (10 g/day), eaten before breakfast, reduces serum UA in CAD patients. Prevention of hyperuricemia can confer protection from kidney and vascular damage and if extrapolated for general population, dietary almonds can offer grander health benefit. Trial is registered at Australian New Zealand Clinical trial registry as ACTRN12614000036617.