Eat 200 more calories as your BMR is around 1,600 calories (NOT 1,400 calories).
DO NOT mess up your metabolism while worrying about your waist and your weight.
You should eat enough calories to cover your Basal Metabolic Rate (BMR) or your body will adapt to a low caloric intake and lower your metabolism, making it very hard for you to use your body fat. And then, as soon as you would eventually start eating normally again, you would make body fat very easily, because you would have a lower metabolism and therefore regain all the weight you lost and keep going up, unless you exercise A LOT.
655 + (4.35 x weight in pounds) + (4.7 x height in inches) - minus (4.7 x age in years)
655 + 702.52 + 314.9 – 79.9 = 1,592.52 rounded to 1,600 calories.
The good news is that you gained weight with depression. You ate enough and did not lose your appetite and did not mess up your metabolism. Some people get depressed, lose their appetite, and lose 20lbs, become underweight (like if you’d weigh 110lbs instead of 160lbs, you’d be in more trouble) and end up with a metabolism down the drain. It’s very hard for them to resume eating normally and regaining weight without developing an eating disorder. It’s hard to eat when you have no appetite, you’re so weak and out of shape that you don’t feel like going grocery shopping, cooking, doing the dishes...and fast food is just a disgusting idea.
You’re overweight now (at 85th percentile), but barely...at your age and height, you would lose just one pound on the scale and get into the healthy category with a healthy weight at 160.5lbs; your BMI would be 25.1, placing the BMI-for-age at the 84th percentile for girls 5’7, aged 17 years.
And do not worry: the overweight category is just a buffer between the healthy and the obese categories. You would need to weigh 190lbs to reach the obese category. Lose just one pound, eating healthier and exercising and you’ll surf back down the healthy category with no problem.
You need to eat less, but still enough to cover your BMR (1,600 calories) and then exercise for 3,500 calories for each pound of fat reserves that you wish to lose, taking as much time as you need, as the slower the fat reserves loss, the better your chance to keep the weight off.
At first, you can lose an inch on your measurements by just getting back in shape. Once in shape, you can lose an inch for every 10 pounds of fat reserves loss. For the same mass, muscle mass is 3 times heavier than body fat (or you could say muscle mass takes 3 times less space than body fat for the same weight so you get thinner without even losing weight).
Once, I went down a size in 3 months, WITHOUT even losing weight because my goal was not to lose weight but to be stronger, toner, thinner and lose my belly pouch. My body fat percentage went down 2%. I was 122.6lbs and 3 months later, I was still 122.6lbs and lost an inch on all my measurements (I’m 5’5).
I lost body fat with aerobics (walking/jogging, biking, swimming…) and gained muscle mass with weight training (calisthenics and using small weights). It was a great experience because I looked so much better with a hint of a curve of muscle definition and everything physical in my life got easier, like going up the stairs or carrying grocery bags.
I tripled/quadrupled my strength (depending on which muscle you’re talking about). The best part is that I would eat more to get enough energy and a high blood sugar level to make my weight training easy and efficient. And I only had to do a daily average of exercising of 300 calories while eating enough to cover my Basal Metabolic Rate (I did 27,000 calories of exercising in 90 days).
The way your body stores fat reserves if different from one person to another (like I cannot make fat reserves on my arms) so you have to know your body and keep notes. I see that you can lose 12lbs of weight and lose 1.5’ on your bust and hips but 2.5’ on your waist. I would guess that the 1’5 difference would be a combination of getting larger because you’re getting bigger but also because you’re getting out of shape and your body is recycling your unused muscle mass, so you get a slower metabolism and gain fat reserves that takes more space for the same weight. The 2.5’ difference in the waist, just for 12lbs, is trickier and can easily be off by an inch on those days when you should not had measured yourself (water retention, periods, irregularity...). Measure yourself only once a month but on that day when you know that you do not have water retention and don’t feel bloated. If you ate salty food, wait a couple of days to measure yourself.
Btw, walking IS aerobic. Maintain the same physical effort and in a few weeks, you’ll be walking/jogging. Once you get in shape, with more muscle mass, weight loss is easier as you have strength, cardiovascular health and a higher metabolism.