It's amazing how easy this is to do. Your goals are a couple of simple calculations away!
Estimating Caloric Requirement
Determine your resting metabolic rate (RMR) This is the approximate amount of calories you burn in a day without exercise and the minimum amount you should be eating.
Body weight (lbs) x 10 calories
160 lbs x 10 = 1600 minimum calories per/day
Now we will determine the daily amount of calories based on activity levels
Sedentary- Add 20-40% to RMR
Moderately Active- Add 40-60% to RMR
Very Active- Add 60-80% to RMR
Sedentary- 20-40% of 1600 calories (for 160lbs) = 1920-2240 calories
Moderately active- 40-60% of 1600 calories = 2240-2560 calories
Very active- 60-80% of 1600 calories= 2560-2880 calories
Now take these numbers and apply them to your goals.
If you want to lose weight, cutting 500 calories/day will allow you to lose 1lb per/week.
If you want to gain weight add 500 calories/day to gain 1lb per/week.
I suggest 500 calories because 3500=1lb. It's also a safe amount to cut back for long-lasting and healthy weight loss.