There are a variety of factors to consider, for weight loss, gain and maintenance. Sleep, stress and hormone balance all make a difference when it comes to weight. For a more in depth discussion of the calories in calories out model of weight loss versus a hormonal model, be sure to check out our Complete Beginners Guide to Keto. Most likely, it’s a combination of both models.
In general though, to lose weight you need to consume less calories than your body needs. To gain, you’ll need to consume more calories than you need. To maintain, you’ll need to consume roughly the amount of calories you expend on a daily basis.
This calculator has a default calorie deficit for weight loss of 20 percent and a default calorie surplus for weight gain of 15 percent. Twenty percent deficit is aggressive and allows for the quickest weight loss but may be hard to maintain for a long period.
To set goals that allow you to gain or lose more slowly, which is more sustainable, use the custom setting for the calculator. About 10 percent is a healthy and sustainable goal.