I never really ate much if any junk or fast food in my life. I don't really have a sweet tongue unless it is Ramadan. My guilty pleasures are probably Lays Paprika chips (the only kind of mainstream chips that I really like, eat them maybe once or twice a year), snickers ice cream and chocolate, lol. Some more too as well that I forgot if I thought about it closely.
As for snacks I am eating a lot of vegetables, fruits, various nuts and of course your typical Arabic "snack" dishes but most tend to be relatively healthy so not a big problem.
I don't gain nor loose weight (maybe it will change once I get older) regardless of how much or how little I eat. I do try to stay fit (going to the gym 2 sometimes 3 times a week, sometimes I don't at all also, the last 2 months have been bad due to a busy schedule, work etc., some running, used to do boxing and play tons of football and basketball - now not any longer as you get older and family, friends etc. don't do it much either).
I eat a lot of fish, seafood, lamb, chicken, vegetables, fruit, herbs, (spices too depending on the dish) use olive oil frequently, all kinds of bread (traditional, pita, ordinary bread etc.), various milk products (cheeses and yoghurt mostly) and drink a lot of water. Stopped drinking much coffee and tea but do drink it weekly just not as frequently as I used to.
BTW I actually try not to eat much (sometimes very, very little food other than some fruit and vegetables or nuts) at least once every week or 2. Some kind of "mini fast". My body does not really mind it and I don't feel without energy or tired and can go to the gym for 1-1.5 hours of some weight lifting and a bit of running without trouble or go for a long walk. Doing your everyday kind of activities without a problem. However I always drink a lot of water during such days and always tend to eat a lot the day before such days.
Obviously not smoking, not eating your typical fast food, not drinking any alcohol, barely eating any non-healthy snacks etc. helps a long way.
So occasionally some chocolate, ice cream and more rarely some chips is not a big deal at all.
BTW I obviously eat falafel, kebab, shawarma, kushari, manaseeh/pizza, mantu samboosa, mutabaq etc. but in healthy amounts and not too frequently.
Obviously I also eat traditional sweets and more of them during Ramadan (as I wrote) because I tend to have a more sweet tongue so a dish like luqaimat is normal.
As
@Falcon29 rightly wrote you can replace sugary foods (especially the not very healthy kind) with fruits, yoghurt and dark chocolate for instance. Being hydrated (drinking lots of water) also helps. I try to drink at least 2.5 l every single day.
Some 1.5-2 years ago I discovered sweet potatoes (very healthy) and started eating them regularly. They are incredibly nutritious and have a somewhat sweet taste. Much better than your ordinary potatoes that I am not much a fan of.
Instead of eating too much rice, pasta/food containing pastry, I have started eating them on a weekly basis. I mostly prepare them in an oven. Taste better than if boiling them.
Great suggestions. I eat oatmeal also and crushed nuts (various) with yoghurt (natural usually). I often add dried raisins too.
BTW I absolutely love Indian naan bread (tandoor oven) with cheese.