Negative Calorie Adjustment

The Apple to MFP interface has a reputation for working in a nonstandard** way, and I'm not an Apple user, so I can't comment on that. (** I.e., an incorrect way, for reasons of how Apple implemented it, as I understand it.)

Speaking about trackers more generically, with MFP:

In MFP you have an activity level, some demographics (height/weight/etc.), and a weight management goal (lose X per week, or whatever). MFP uses those pieces of data to estimate your current maintenance calories, then subtracts some calories from that if you asked to lose weight (adds some if you wanted to gain) and gives you a base calorie goal to eat, to accomplish your weight-management goal. However, it won't put you below the minimum calories of 1200 for women, 1500 for men.

Philosophically, you're supposed to set your MFP activity level based on daily life activity excluding intentional exercise (job, chores, etc.), then log your exercise when you do some, and eat those calories too, keeping the same weight management goal intact.

Your fitness tracker measures various aspects of what you do all day (maybe arm movements, heart rate, distance per GPS, altitude changes, etc.), and estimates how many calories you burn doing what you do, also using demographic data in your user settings for that device.

When you synch a fitness tracker to MFP - still speaking generically, not in terms of Apple's implementation - it effectively does two things. One is to recognize calories from your exercise (in effect, may or may not create line items other than the general adjustment number, depending on the device). The other is to decide whether you were right about your activity level, and adjust if you weren't. (Again, that may just be lumped into one adjustment number.)

Periodically, MFP and the tracker compare notes and exchange data. The core of this is to compare the tracker's total calorie number to MFP's expected maintenance calories, and adjust your eating goal in MFP to keep your same weight management goal in play (i.e., lose X pounds a week, or whatever). In effect, the adjustment covers both exercise and daily life activity. With some devices, it may be adjusted and re-adjusted multiple times over the course of a day, but by the end of the day, they should be in agreement (the "why" may not be obvious).

If you enable negative adjustments, MFP will feel free to remove calories from your goal that day (if you're less active than the base maintenance calorie level it expected), reducing your eating goal.

If you don't enable negative adjustments, MFP will only increase your eating goal if you're more active than it expected. If you're less active than it expected (with negative adjustments not enabled), there's zero adjustment. In effect, that would give you a slower loss (or faster gain) than you asked for.

Like I said, my understanding is that Apple doesn't do this correctly, so results may differ. I've read here that if you synch Apple to the Pacer app, then Pacer to MFP, that will work right . . . but I'm not an Apple person, so I haven't done that.

stephaniea09 wrote: »

Can someone provide a better explanation of what Negative Calorie Adjustment is? The explanation on the website is very confusing to me.

A bit about my situation: I wear an Apple Watch all the time and track my workouts on it. I have Apple Health linked to MFP and I have also selected my Apple Watch as a pedometer to track my steps and log them onto MFP.

Right now in my journey I am currently using up my additional calories that I have earned from workouts as more food (I think my Active Level is off and I am more Active than I assumed).

Is Negative Calorie Adjustment for me? Thanks!

Most of these trackers provide a reconciling calorie adjustment between what you've set as your activity level in MFP and what your actual activity level is per your device on a given day. If you're set to sedentary and you are more active than that per your device, you get a reconciling adjustment up. If you're activity level is set higher and you're not actually that active, you get a "negative adjustment" to reconcile the fact that you aren't actually as active per your device as the activity level you selected in MFP.

I feel dumb, I still don’t get it. I use an apple watch and am trying to lose about a pound a week and generally I get a +300 something calories added to my amount per day for activity. Are you saying Apple is calculating something wrong and I should ignore that 300 and only eat to my base #?

Would allowing negative calories only confuse me more?

@heybales - thank you!



This is a pretty typical day for me. The 3 short leisurely walks are walking my dog (shorter due to weather) & the others are my apple fitness plus “classes” - typically HITT & strength training. & 5 min of pilates, core or cool down yoga/stretch.

I see it has my steps with a 0 ext to them.

does this help? Am I good just doing what I am doing and assuming it is ok to eat most of those 300 calories back? or should i use the negative adjustment? It all still confuses me which is why I usually eat about 150-200 of them and call it good.

ok, here is what I got from the same day, hope this is right




thanks for showing me all this stuff I didn’t know existed on this app!

@heybales Thanks so much, this helped a lot! Apple had my total expenditure that day at 2407 so a 300 difference from MFP.

I think I am going to turn negative calorie adjustments on for a bit and see how it goes. 👍🏻🙂

You can’t edit an Apple Watch exercise within apple, although you can edit it once it transports into MFP.

I presume that’s to keep people from cheating on challenges.