I have noticed that if my ph drops to 6.5, which is considered acceptable on the low end, that my energy and mood sag. On the other hand, if I let my ph go up to 8 or even 9 ph once a day then I feel stronger in those ways all day. Most of the day I tend to be at 7.0 to 7.5, but those daily high spikes (from using baking soda & lime juice with lots of water to protect the kidneys, once a day) help me feel better than if I stayed 7.0 all day.