Three weeks is very little time to see a change. I know we all want to see results NOW .. .but give it a bit!
As far as DP goes, I use them to log food and keep track of calories, but I think their whole system of net calories and eating back exercise calories is totally screwed up. They make what is a simple thing *so* unnecessarily confusing and complex.
Eat a reasonable level of calories. Exercise. Don't try to figure out complicated calculations of eating back. Just eat at a healthy level and let everything balance out in the end.
I personally eat between 1300 and 1500 cals a day (try not to go over 1500, although I'm not always successful) and I exercise 4-5 times a week. I don't try to figure out how many cals I burned and eat them back. I just burn them.
So far that works. And it doesn't require me to become a math whiz.
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