I've been thin all of my life - and then my 30s hit. And weight didn't come on all at once, but it creeped in pound by pound because I kept the lifestyle of a 20 year old: eat what I want, when I want, and who needs exercise? I only had to lose 20 pounds but it was the hardest 20 lbs of my life and took forever. I would lose a couple and plateau forever, and it seemed if I even looked at food I would gain it back. Learning to exercise was so foreign. Like I said, I've kept it off for 7 years. Now, it doesn't take much effort because I don't take it for granted anymore and I am conscious of my activity level and calorie intake. When I first got to my goal weight, it was a daily struggle to stay there for a long time. I highly suggest a food diary or phone app that does it for you. I loved the app because it not only tracked my calories but proteins, carbs, fiber, etc., my calories burned and my weight gains and losses. It helped me stay on track, focused, and helped me learn so much about what I can have and when because I had a record of when I lost, when I gained, when I plateaued, when I maintained. I did it for a so long that now I just know and don't have to track it anymore.