I lost that amount roughly over 6-7 months, with some stalls and fluctuations (went on a vacation, managed to keep weight steady despite eating out a lot). I have been overweight for many many years, gaining the most in 2012. I did not go to the gym during my weight loss, but have now started to hit up the gym. I definitely lost some muscle in addition to the fat, which is why I have been going to the gym to bulk up (need to start going consistently!).

I limited myself to 1200 calories a day. http://www.reddit.com/r/1200isplenty is a good subreddit if you are looking to do the same, but I never recommend people to do what I did. I recorded everything in myfitnesspal very strictly.

There was a period where I worked a lot (was a part time active job), and as I have a tendency to stay out late, I would wake up the next morning and immediately go to work to maximize sleep (skipping breakfast, often skipping lunch too and just drinking a meal replacement shake as my 'brunch'). I will NEVER recommend someone do this (I was literally consuming under 1000 calories a day). This was the worst period for me, I felt EXTREMELY weak, the weight was barely coming off, and I fainted one morning before work. That was the indication for me to smarten up, and I fixed my diet.

I cut out carbs (except for certain days where I may have brown rice or that grainy bread), and mainly ate chicken, tuna, and fish.

People are shocked when they look at me compared to before, and I constantly get asked what I did. I tell them, full disclosure, I do not recommend everything I did. I tell them my mistakes (how starving yourself is never a good idea), and what worked for me. What I recommend to them is consistency, which was the biggest factor in weight loss. Count calories, be as active as you can, but MINIMUM 1200 calories (which is still low). Gradual weight loss is the best, it will happen as long as you are consuming less than your BMR, and do NOT get fixated on the scale. That is what caused me to go over the edge, fixating on the scale. Once I got past that I was fine.