zERo_OveRiDe

I seem to be having success overclocking my 5820K, however I'm not familiar with long term effects of OCing. I have a NZXT Kraken X-61,supposedly ideal for OCing, cooling my CPU which is clocked at 4.5Ghz with no apparent problems. My idle temp is 28-30 C and workload temps reaching at the highest 70 C. Is keeping this OC setting for daily, regular use killing the lifespan of my CPU? Should I only OC when extra power is needed?