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Background/objectives: Intermittent energy restriction (IER) may overcome poor long-term adherence with continuous energy restriction (CER), for weight reduction. We compared the effects of IER with CER for fasting and postprandial metabolism and appetite in metabolically healthy participants, in whom excess weight would not confound intrinsic metabolic differences. Subjects/methods: In a 2-week randomised, parallel trial, 16 young, healthy-weight participants were assigned to either CER (20% below estimated energy requirements (EER)) or 5:2 IER (70% below EER on 2 non-consecutive days; 5 days at EER, per week). Metabolic and appetite regulation markers were assessed before and for 3 h after a liquid breakfast; followed by an ad libitum lunch; pre- and post-intervention. Results: Weight loss was similar in both groups: −2.5 (95% CI, −3.4, −1.6) kg for 5:2 IER vs. −2.3 (−2.9, −1.7) kg for CER. There were no differences between groups for postprandial incremental area under the curve for serum insulin, blood glucose or subjective appetite ratings. Compared with CER, 5:2 IER led to a reduction in fasting blood glucose concentrations (treatment-by-time interaction, P= 0.018, η2p= 0.14). Similarly, compared with CER, there were beneficial changes in fasting composite appetite scores after 5:2 IER (treatment-by-time interaction, P= 0.0003, η2p= 0.35). Conclusions: There were no significant differences in postprandial insulinaemic, glycaemic or appetite responses between treatments. However, 5:2 IER resulted in greater improvements in fasting blood glucose, and beneficial changes in fasting subjective appetite ratings.

This study investigated the effects of cerium on the regeneration and biosynthesis of ascorbate and glutathione in the leaves of turf grass Poa pratensisseedlings under copper (Cu) stress. The results showed that Cu stress increased the activities of ascorbate peroxidase (APX), dehydroascorbate reductase (DHAR), monodehydroascorbate reductase (MDHAR), glutathione reductase (GR), l-galactono-1,4-lactone dehydrogenase (GalLDH) and gamma-glutamylcysteine synthetase (γ-ECS), and the contents of reduced ascorbic acid (AsA), reduced glutathione (GSH), total ascorbate and total glutathione. However, Cu stress markedly increased the malondialdehyde content and electrolyte leakage and decreased the fresh and dry weights. Pretreatment with cerium (Ce(NO3)3) enhanced the activities of APX, GR, DHAR, GalLDH and γ-ECS, and the contents of AsA, GSH, total ascorbate and total glutathione under Cu stress. Meanwhile, pretreatment with Ce(NO3)3decreased the malondialdehyde content and electrolyte leakage and increased the fresh and dry weights under Cu stress. Our results suggested that Ce(NO3)3alleviated oxidative damage by regulating the metabolism of ascorbate and glutathione under Cu stress, and has important role in the acquisition of Cu tolerance in P. pratensisseedlings. Therefore, Ce(NO3)3can be used as a regulator to improve the Cu tolerance of P. pratensis.