BMR vs. TDEE

kecward78

I started my journey about 2-3 weeks ago and have gone from 402.7 down to 393.4. Sounds great but I'm concerned about losing too much too fast. I want to lose slow and steady since 1) I don't want loose skin (or as little as possible), 2) I want to keep it around 2 lb. per week loss, 3) I'm confused if I should keep my calories under my BMR or under TDEE. I'm a 5'10", 59 year old male. I'm also slowly starting into DDP Yoga and want to add weight work for overall health. I'm working under a 'fewer calories in than expended* produces weight loss (i.e. not making major changes to diet). I have substituted stevia for sugar and am trying to keep my macros under control (especially carbs). So do I use the base BMR for calories or the more expansive TDEE which might give me as much as 800 more calories per day? Help!!!

MikePTY

It is normal for peoe with a lot of weight to lose to see large losses in the beginning. A lot of it will be water weight. Your loss is not anywhere out of the ordinary. I would not worry that.

If you are calculating yourself, you use TDEE, not BMR, to generate your goals. BMR is how much you would burn in a coma. So starting with that will give you too low a calorie goal.

But the easier thing to do is to put your stats into MFP, tell it you want to lose 2 pounds a week, and then eat the calories MFP tells you, plus a reasonable estimation of calories you burn from exercise.

PAV8888

Under TDEE.

Usually a reasonable deficit off TDEE for someone obese would be an up to 25% reduction. Once overweight/normal weight a smaller 20% reduction may be more appropriate. Unless one is extremely sedentary such reductions will result at food intake above BMR.

A second rule of thumb is that weight loss of between 0.5% and 1% of body weight a week is usually well tolerated.

From what I've seen most people who keep to the no more than 25% of TDEE deficit do not exceed the 0.5 to 1% body weight lost range.

IF YOU ARE REDUCING CARBS, you are "BORROWING" an extra boost of scale weight reduction that is going to come back whenever your carb intake is restored. This is NOT fat weight. Changing your intake of carbs COULD affect your level of glycogen in your body and each gram of glycogen lost or gained is accompanied by 2-3g of water that is used to store the glycogen in your body.

In general, when starting a deficit some changes are made. Less food is circulating in our body. Sodium may be reduced. As discussed some glycogen may be lost both due to carb manipulation and due to the deficit that is applied.

I would personally exclude the first couple of weeks of weight loss from any calculations of my rate of loss.

I suggest you may want to start using a weigh trend application. It is a nice tool to have and it may help you dial in your loss as time goes on (after 4-6 weeks sort of thing). You can achieve the same thing with a spreadsheet and a trendline; but most of us find it easier to just use an app or web site

@NovusDies has a sub forum going that might interest you to join.

corinasue1143

What he said.
Start watching the scale today. The first 2 weeks or so, your body is adjusting to your new way of eating, so your rate of weight loss may not be representative of your long term weight journey.

lgfrie

First, congrats on getting things underway. I started DDP Yoga in 2012 and really benefited from it, though I didn't continue with it. It didn't help with weight loss but man did it help a LOT with flexibility, strength and general well being. I love the DDP videos. Needless to say, as the videos demonstrate superbly well, people who get seriously into DDP Yoga do achieve significant weight loss benefits too, I just didn't push myself hard enough with it to burn fat. But it's very possible to do. Plus, I like DDP's whole vibe.

Anyway ...

OK, you are not losing weight too fast. When you are very heavy, the first 2-3 weeks of dieting entail massive scale weight drop, and this continues at a slightly slower but still somewhat unusually fast pace for a total of 5-6 weeks. Around week 6, the pace of scale weight reduction will slow to a crawl and a lot of people get demoralized at that point because they secretly thought or hoped they had it nailed - eat less and lose 4-5 pounds per week. Nope. Doesn't work that way, ever. Your 3-4 lbs per week for the first 2-3 weeks is completely normal. Most of that is water. When you start dieting, the water your body is retaining to balance the carbs and sodium is gradually rebalanced since you're not taking in as much carbs and sodium as you were before dieting. Eventually around week 6 everything will be in balance and then you will then be on a long, slow, challenging grind to lose weight. So ... enjoy the quick, easy part while it lasts and don't worry. You are not losing fat too fast. Scale weight and fat loss are two different things. If you go out and binge for one night, all but around 4-ish pounds you lost will come right back, because only 4-ish pounds of fat have been lost; the rest is just water and doesn't matter.

Moving along ...

BMR is the amount of calories you burn doing absolutely nothing. In other words, it's how many calories you'd burn if you were in a coma, to keep your heart pumping, basic metabolic processes going, etc. It is not a useful number to work with because it's theoretical and abstract - no one burns just their BMR. Its only purpose is to provide a baseline number that can then be multiplied by a coefficient to estimate "actual" calorie burn.

TDEE is just that - an estimate of how many calories you actually burn per day, based on multiplying your BMR by a coefficient, usually 1.25 if you're sedentary, or higher if you're more active. Very obese people usually fit into the "sedentary" category pretty well.

So for instance, if your BMR is 2,000 and you're sedentary, your TDEE might be estimated at 1.25 * 2000 or 2500. Note that word "estimated". TDEE is just an estimate, although as it turns out, often a very good one. Your exact TDEE will be specific to you and the only way to nail it down with precision would be to weigh yourself for 6+ weeks while monitoring every single calorie going into your mouth. Then you'd have the requisite data set to calculate your TDEE. Most people don't do this and rely on the estimates from sites like tdeecalculator.net, which are surprisingly accurate!

To put this all in perspective, TDEEcalculator.net says my TDEE is 2434 based on my age, gender, weight, height, and "Sedentary" activity level. My actual calculated TDEE based on my own Excel spreadsheet and my maniacal bordering on OCD data logging and number crunching is 2451. In other words, the calculator site is within 1 % of my actual data, just 17 calories off, which is quite incredible when you think about it.

The best thing you could do to get the ball rolling would be to go to the MFP Goals tab, enter your gender, age, weight, height, activity level, and tell it you want to lose 2 lbs per week, and see what number it gives you. Whatever number it spits out, eat that, and you'll lose 2 pounds per week, plus or minus 10 %. In my case, their goal calories have been DEAD ON for 2 lbs per week for over six months!!!

You can save yourself all the heavy lifting and eliminate any and all confusion by letting MFP do the work of coming up with your calorie target, so that's the way to go. Then the important part becomes complying with it day in and day out. Try not to take cheat meals or off days, and don't go over or under the calorie target - get as close as you can to it, as often as possible, and you'll get the results you want.

kecward78

I just wanted to thank each of you that replied already. I was able to take a bit (at least) from each of you and incorporate it into a plan. Most likely, I will just allow MFP to set it up and, with my FitBit, use it to track and adjust as we go. Thanks again!

earlnabby

kecward78 wrote: »

I just wanted to thank each of you that replied already. I was able to take a bit (at least) from each of you and incorporate it into a plan. Most likely, I will just allow MFP to set it up and, with my FitBit, use it to track and adjust as we go. Thanks again!

Sounds like the perfect plan! I found it takes about 5-6 weeks to settle into a somewhat regular weekly loss rate. First you lose a lot (much of it water), then your body may need to add back in some of that water because it dropped too much so you go a week or two with no loss, them you start losing at a fairly normal rate. You are losing fat the entire time. If you take the first 6 weeks and average out your weekly loss, it usually ends up pretty close to projected. If you are still losing faster than you are comfortable with, make the necessary adjustments.