Is he on any meds? Someone told me the other day that metformin can cause those kinds of problems but when I looked it up it turns out that it uses up your vitamin B-12 quicker and that can cause memory loss in itself. Statins also can have this effect on some people and so can drugs like benadryl or tylenol PM(anticholinergics). These days I take a good vitamin B supplement with choline in it, and then I take a sublingual B-12 on the side and I make sure I get the methyl- form, not the cyano- form, because you're supposed to absorb it better. I do this b/c I have a family history of B-12 deficiencies.
Also, does your uncle have a weight problem? If he does then surely he has problems with insulin and processing sugar and studies are coming out that this can be really bad for your brain--you don't even have to be diabetic to get brain damage. It's really scary. This effect can be short term (right after a really sugary meal or snack) or it can do long term damage. I know I get plenty stupid after a sugar binge.
As for the puzzles--I'm not sure what I think of that unless you switch up what you do. Turns out that getting into a rut is far worse for your brain than being active and busy and changing things around. I do sudoku a lot and I'm getting where I can almost do them in my sleep--any activity that you can go on autopilot while you do it is not going to be beneficial. It may not be bad, but it probably won't help and the longer your mind is actually engaged, the better. I read an article that said that it's far better to do things like take a different route home from work on some days, meet up with different friends periodically, go somewhere different for a vacation, or even change the living room around. Things like that. Oh yeah and learn something new. Pick up a musical instrument, even if you're not musical. Or
especially if you're not musical.
Exercise is always good but I've heard the absolute best and gold standard is dancing. You move and get winded, you have fun, you're social, and you have to think about what you're doing.
I did a lot of research on this stuff when mom was sick with her dementia, but turned out she had advanced cancer instead and probably a tumor in her brain so it wouldn't have helped anyway. Oh well, I'm glad to know this info.
Look at this list first and then if you want, I know of a lot of different supplements that are supposed to help, but at least make sure he's getting a good multi and add B vitamins and C will help to absorb the choline. You can even get a choline and inositol supplement that has a lot of choline but I'm not sure what that would do long term. Probably couldn't hurt for the short term though.
Oh yeah and OP: drop the idea that your uncle is old. 60 is
way young to be showing signs of dementia so this is most def not normal signs of aging. If he were 80, then it might be understandable if a few things fell thru the cracks, but dementia is a disorder, not ever a sign of normal aging. My g-ma was sharp into her 90's and though she did start to forget a few things, she was mentally capable of living in her own home until the end and did.