If you have a fitbit/jawbone or any fitness tracker , then this is simple. In the interim, continue doing what you're doing with the calories MFP tells you to eat. Next, I would suggest you wear a fitness tracker for a week and learn more about the daily calories you are burning. Write down the amount you burned for each day. Find the average amount of calories you burn.

From there , you subtract roughly 900 calories (this is your deficit, and it could be lower like 600, or higher like 1000 depending how agressive you want to get with your weight loss) from that Average Daily, to get the amount of calories you should eat. You put that number into MFP for your overall daily calorie goal and ignore all MFP suggestions about daily calories needed. After that you just set up your macro goal percentages for low carb (high fat) 70 F/ 25 p/ 5c or your choice of any suggested low carb macros. At the end of each day, subtract the amount of your calories eaten in MFP from the amount showing on your fitness tracker for calories burned, to ensure you hit your deficit goal (900, 600 or 1000)

Don't forget to always enter your food into MFP before you start eating it weigh, measure , enter into MFP, weigh, measure , enter into MFP!

I like to view it like my meal ticket... I only get a meal after I do the work up front that is required for it , weighing , measuring and entering the meal to MFP, then making any adjustments on the quantities or choices.