I was recently challenged in a verbal exchange that complaining is human nature. That it is something that we just do and that it doesn't mean that anything is wrong. I immediately challenged this idea, as my own understanding of complaining is that it is indeed a sign that something isn't right and an invitation to reflect and improve upon a situation. This came across as a lecture instead of a fair point yet caused me to explore the concept of complaining a bit further. The Merriam-Webster dictionary defines complain as: to express grief, pain, or discontent. Synonyms include: beef, bellyache, croak, fuss, gripe, nag, moan, whinge (British) and grumble. There are several more but these give us some vocabulary to consider.
Entrepreneur magazine published an article on research finding that, "most people complain once a minute during a typical conversation." It seems that people do it because it feels good, much in the way that smoking or eating unhealthy food feels good. We know that these have unhealthy consequences. Human brains are wired for efficiency and when behaviors are repeated, neurons branch out which result in an easier glide of information. This is what makes such behaviors easier to repeat again and again, often without our even knowing it.
MRI scans have revealed that the effect of constant complaining can lead to shrinking of the hippocampus. This is the part of your brain which is associated with learning, emotions, and new memories (cognitive functioning.) A smaller hippocampus = memory decline and difficulty adapting to new situations. Complaining leads to an increase in cortisol levels, cortisol being the "stress hormone". This opens a big can of worms as there is plenty of information out there on the negative effects of stress. All of this is evidenced by a Stanford study stating that 30 minutes of complaining or even being complained to, can physically damage the brain.
It isn't easy to be around people who frequently fuss, gripe, or grumble. Yes, it seems that everyone does it and some more than others. In the spirit of mindfulness, we might be better served by noticing when it is happening, either coming from ourselves or from others, and the effects of this. In that space of noticing, perhaps we can respond skillfully and compassionately. After all, change comes from within, not from without.