Hi, I have been with Mfp since end of February & purchased a fitbit zip a few days later, I have never eaten back the calories from my fitbit unless eating out etc as never felt a need too but somebody noticed my net goals were becoming quite low, I want to lose the weight sensibly at around 1 pound a week, I have read several articles but its confusing me even more, I have looked on the fitbit main dashboard & my daily average calorie burn is between 2300-2500 approx as each day is so different, do I set my tdee at around 1800 cals a day (-500 cal deficit from what I've been burning for the pound a week Loss)? Thanks if you understand all that, hate being so thick at times x

I haven't read all the posts yet so am probably repeating some. But I see one misunderstanding to clear up right away. First TDEE is an acronym for Total Daily Energy Expenditure which could also be referred to as your "calorie burn" for the day. So, your TDEE cannot be less than what you burn as that is suppose to be your total calorie burn. Each day your true TDEE will vary depending on how active you are, what and how often you ate, whether you recently did vigorous exercise, and possibly what is going on with your hormones that day. If your fitbit burn ranges from 2,300 -2,500--that is your TDEE. Where are you getting 1800 calories? Of course all calorie burn estimates (and online TDEE calculators) are estimates not direct measures. Individual calorie burn and metabolism is a little more complicated than the formulas can work out as there are a lot of variables. The formulas estimate averages based on your stats and should put your close--maybe a little high, maybe a little low. So there is trial and error with real life results vs what shows on paper/screen. The issue with TDEE calculators (I am guessing that is where you came up with 1800) is that they rely on you subjectively guessing at your activity level and usually have some vague description to help you guess (sometimes your job like MFP uses and sometimes how often you workout like the Scooby calculator does). It can be hard to accurately choose the right multiplyer based on either of those factors in isolation (job or workout frequency). By workout frequency, I would choose very active or extra active but my fitbit calorie burn usually puts me more a little higher than lightly active and sometimes a little higher than moderately active. By job, I would choose sedentary which would usually be too low. I think the benefit to using Fitbit to calculate your TDEE is that your fitbit tracks how much you move and factors in any activity you log. It isn't using a subjective standard. I do think it is a helpful exercise for people to use a TDEE calculator and run their stats at every activity level to see the range of what they might expect. This can be especially helpful for people with a higher BMR than they would guess and who are active as they are often shocked when they first start dieting and using a device like the fitbit to estimate calorie burn.

I don't really worry much about "net" as MFP uses the term. It is only in relation to whatever goals you set on MFP. It is possible for your MFP "net" to be way too high for your body (usually only if you set a poorly calculated custom allowance) and it is possible for your "net" to be too low for your body (if you set a poorly calculated custom with too aggressive a goal for your bodyfat level). Really to lose weight, we are always in a negative "net" because we want to burn more than we eat. If you are eating a 500 calorie deficit, your real "net" should be -500 since you are eating 500 calories less than you burn. I think MFP's net does over complicate this and I have only seen this term used this way on this site. But saying that, the reason MFP promotes this "net" is for your health. While to lose you do need to eat less than you burn, you don't necessarily want to eat too much less. You metabolism does depend on your generally being healthy and having a healthy hormone balance which depends on you getting the vitamins, minerals, protein, essential fats, etc that you need to stay healthy. That becomes very hard to do on a very low calorie diet. If eating 1200 calories (MFP's minimum) and very accurately tracking food (weighing portions, etc) you would really need to focus on only eating highly nutritious foods to meet these needs within that limit. Okay, maybe 1200 you could enjoy an occasional treat, but when you get to the 1000 calorie diets that use to be promoted among women it gets that much harder. Also when dieting it is common for metabolism to adapt as the body doesn't want to starve--so it slows somewhat (not to imply starving people do not lose weight--they do obviously. They just do it slower than they would if they ate more). And too fast a loss, especially without a good strength training program tends to result in loss of lean mass like muscle since the body will use some of your muscle as protein if you are not eating enough. How low you can safely go before running into those issues seems a matter of great controversy and the more you read the more confusing it is. But I guess to me it makes sense that the body needs nutritious food to function well and on too limited a diet it is just hard to meet the needs (and hard to be consistent with compliance). So why undereat by more than you need to in order to see a healthy rate of loss? The risks seem too high compared to short term benefits. Most people I know who have done very low calorie diets tend to fall into a pattern of yo-yo dieting where they lose some than regain it as soon as they stop dieting, over and over often regaining more and more each time. Sorry, even though I disagree with the "net" as MFP uses it, I do agree with the principal that it is better to eat enough to allow for good nutrition. And about not eating less than you have to...

Your BMR is meant to be the calories someone like you would burn if in a coma all day--no movement at all. It is the calories your body uses to run your organs and regulate body temperature. Sometimes people can be healthy eating less than their BMR--but usually only morbidly obese people with very high BMR's. In that case a doctor might feel the health benefits of weight loss outweigh concerns about decreasing metabolism or losing lean mass, etc. But for someone only moderately overweight or in a healthy weight range just plumper than they would prefer--it probably isn't a good idea to eat less than BMR on a regular basis.

The starting place to lose 1 pound a week--your total calorie burn each day minus 500. So with your range... On a less active day you would eat 2300 - 500 = 1800. On a more active day you would eat: 2500 - 500 = 2000. So usually 1800-2000 depending on activity. But you don't have to do this math every day--either MFP or Fitbit will do it for you if you set up the "guided" plan incorporating your weekly loss goal.

Sometimes people on this site use a TDEE method of dieting. There are pros and cons to this--but it can work well. I think this is where people get confused though. With a TDEE method, the idea is you would eat according to your average calorie burn (including exercise). Some days you would have a higher deficit because you burned more than your average and other days you may have a lower or even no deficit because you burned less than your average. But if you chose the right average, you would still lose weight at a similar rate to someone eating according to their daily burn because it would average out. One benefit for this is it allows people who like to plan to plan their meals (which may lead to better success if able to stick to their plan). People without fitbit's need to rely on calculators to guess a their average TDEE by choosing the activity level they believe applies to them. Sometimes they choose well and it works, sometimes not. Since you have a fitbit, you can get a more accurate average TDEE if you want. I expect someone will have posted how to do this--if not I'll post again after I read the other posts.

I also appreciate this information.

I have a Fitbit One, and this month I dedicated myself to trusting the numbers. I am not very good at picking my activity level as it changes all the time, I have a sit down 8-9 hour job and work out 3-5 times a week - with varying times. On this app and the fitbit app, I set it to sedentary, a half pound weight loss per week, negative adjustments, and estimations off and using default stride lengths (never took the time to figure it out my strides). Any extra calories I get on this site (MFP) from my Fitbit One..I eat...leaving 50-75 cals on the table for any adjustments I may have screwed up or miscalculated...and to my surprise, I've seen a loss. I was always very hesitant to trust it -after pinging several people on this site, it was time to try. We will see what the rest of the month brings as its still early.