There is a moment when you get older when your metabolism slows down and you don't feel like working out any more, so you don't want to keep yourself fit any more, but that's your decision. Why should you be judged for it? ↗
I believe in eating smaller meals more often throughout the day to keep the metabolism going. Don't deprive yourself, just make better choices. At 50 years old it is definitely a lot harder to stay in shape then it was when I was in my 20's. ↗
My advice is to give up stevia, aspartame, sucralose, sugar alcohols like xylitol and malitol, and all of the other heavily-used and marketed sweeteners unless you want to slow down your metabolism, gain weight, and become an addict. ↗
While weight loss is important, what's more important is the quality of food you put in your body - food is information that quickly changes your metabolism and genes. ↗