The gold standard of sustainable weight loss appears to be intermittent fasting
Ive always been in decent shape until i got to my early 30s and i noticed all my "slim fit" shirts starting to fit a little tight around the belly. Funny, but my first thought was that my shirts shrank in the wash.
It was troubling because i was already eating a pretty good diet. Stopped eating beef, couldn't remember the last time i went to McDonalds, my fast food dish of choice was a 6 inch subway club. So i ate pretty good..... or so I thought.
While my individual meals were guilt free and low in calories I was screwing myself by constantly snacking. It took me having to rebuy alot of my shirts one size up before i realized what i was doing.
So In order to lose weight a new diet wouldn't have helped, as i really was eating fairly healthy, the answer was intermittent fasting. It works because it really isnt a diet, unlike the keto diet or Atkins you dont have to change the foods that you eat. What intermittent fasting does is force you to eat less by restricting the number of hours you can eat per day. The key is you can still eat the same foods.
I think this is now the gold standard for weight loss.