I'm 70, and have been 'heavy' all my adult life. I'm short.....5'7", so when I tell you my weight a year ago was 265#, you get a general idea of my proportions. In February, I started dieting. I tried Weight Watchers for about a month, but found it involved way too much bookkeeping for my taste. I just ate a lot of salads and Subway Veggie Delight sandwiches. In April, I had lost a few pounds, and started riding the bike. It was short rides at first--maybe 3-4 miles. As time went by, the rides got longer and faster, until now I am riding about 15 miles a day.
Unfortunately, I haven't gotten any taller, buy my weight has dropped to just under 200#. My waist has gone from 46" to 36", and I've dropped two shirt sizes. I look a lot different than I did in February, and I'm grateful for the change. I hope to lose maybe another 20# over time, but there's no hurry on that. The physical realities of being 70 years old do limit my abilities a little, and there are the odd days when I wake up and the knees won't bend. There are far fewer of those than there used to be, so it's all good.