I have, as I understand lots of men my age (41), an increasing number of moles.
How often is it sensible to go to the doctor to check on these?
The official advice that growth is one of the signs isn't really very helpful given that a mole that appears (or gets bigger) is by definition growing.
Not sure what your question has to do with the liver which is the forum you are posting on. However, regardless of that, if you are worried about any moles on your body regardless of whether they are new or changing/growing then you should go to the doctors to get them checked out.
Moles can be removed if they are in llocations likely to cause issue and of course any that have changed should be examined as they can be an indicator of skin cancers.
If you are worried, go and get them checked, same as if you are worried about any lumps, bumps or changes in health. Men are notorious for not getting stuff checked.
All the best with it, Katie 
I just wonder if you are confusing Moles and Liver spots? Liver spots have nothing to do with the Liver function, they are just a type of old age freckles if you like.
Moles if they grow, are usually harmless. If you suspect one that looks rough, or crusty, or bleeds, or itches, get it checked out. Otherwise we all get moles and spots here and there as we age, mostly nothing to worry over.
I have moles and visited my gp. It is not unusual to have moles appearing as you age. One of mine started to bleed and after visiting my gp he arranged a visit to a consultant at my local hospital. My bleeding mole was caused by having a low platelet count and not a sign of something more sinister. I would see your gp and follow up at the frequency he suggests.
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