Stress resistance has not been assessed however and so the biological relevance of this finding is currently unknown.32
Several IER trials (75 - 85 % ER on restricted days) in overweight / obese populations have reported reductions in various markers of oxidative stress 37, 41, which in one study was accompanied by a complementary increase in the anti-oxidant uric acid.37 In a direct comparison of IER (75 % ER for two days / week) and CER, both ER strategies displayed equal efficacy in reducing levels of fast - acting advanced oxidation protein
products (AOPP) after six months, which displayed a tendency to occur earlier (i.e. at three months) in the IER group.41 Levels of slow - acting (i.e. long term) AOPP tended to decrease in the IER group and increase in the CER group which the authors proposed may have resulted from IER - induced activation of autophagy, a key homeostatic
cellular process in which dysfunctional or unnecessary
cellular proteins are degraded and recycled.41 On the other hand, a follow - up study using similar IER / CER protocols demonstrated comparable reductions in AOPP in both groups after three months.48 Summary and Future Research Directions