BMR and TDEE Explained for Those Needing a Guide

After posting and learning about BMR and TDEE from some great people on this forum, I finally got a full understanding of BMR and TDEE. I just emailed a friend at work all that I learned as we changed our lifestyle and eating at the same time - I thought a copy of my email may help those in the forum seeking a "dummies guide" to BMR and TDEE..............hope it helps!

Ok, now second, BMR and TDEE:

So in wanting to lose weight, people get confused and frustrated early on when doing a diet or making a lifestyle shift like being plant-strong. Initially, esp on this way of eating, we all had big drops - much of that is due to inflammation from the bad food we were ingesting or water weight.

The mindset you have to force yourself into and reiterate is that realistically, weight should come off slowly as your body re-learns how to get nutrients and burn off fat again. Your body does not care that you want to drop "x" amount of weight in so many months - its only job is survival.

So, like many, I thought with my online tracking system thru MyFitnessPal.com, that I should listen to its "recommendations" (and many docs say this too), to restrict not only portion size but the amount of calorie intake to 1200 a day. The problem is that many of us require 1500 or more a day to simply live, to keep our heart beating, to make the brain work - at minimum we need 1500 or more given to us if we were lying in a coma in the hospital.

Given that fact, what we are told with 1200 cal/day is simply false and very detrimental to our bodies. Some call it "starvation mode" but a more accurate description would be "nutrient deficient." The body looks at that 1200 calories and says, ok, I need (in my case to get specific) 1529 a day to keep you living and breathing and you are giving me 1200, a 300 deficit.

So, in order to keep you living and breathing, again, the body NOT caring about weight loss, the body will slow or stop some other systems (metabolism being the 1st it stops) and hang on to those 1200 calories b/c all it knows is that you are under-feeding it and so it must "hoard" that 1200, store it as fat and keep you alive. You essentially are stopping the metabolic process to a halt when you undereat.

If you can get your head around that concept, then it becomes easy to see, much like a cell phone needing to be charged to turn on and work, your body, your metabolism, NEEDS at minimum that 1529 (in my case) and MORE to really work efficiently, keep me alive AND burn and lose weight. That 1529 # is called "BMR" - basal metabolic rate.

To figure out what your individual BMR is, there are many online calculators - trust me I think I found them all. And although no two will be identical, as I ran my #'s, the results were fairly close to 1529. I read a very informative post on MFP reg on this topic and the site they recommend is this:

https://www.calculator.net/bmr-calculator.html

And specifically, to get your most accurate BMR, they ask first, that you run the Army Body Fat Calculator:

https://www.calculator.net/army-body-fat-calculator.html

That will require your:

• sex
• height (in inches)
• weight (in pounds)
• neck measurement (in inches)
• waist measurement (in inches)
• hip measurement (in inches)

When you submit this info, the system will generate your true body fat %. Jot that % down on a piece of paper, then go to their BMR calculator link at:

https://www.calculator.net/bmr-calculator.html

And plug-in:

• age
• sex
• height (in inches)
• weight (in pounds)
• GOAL weight (in pounds)
• and that body fat % you just wrote

Now, a caveat - for GOAL weight, they ask that you enter in your current weight again - the reason being that when you enter your true GOAL weight, the system will show you a BMR to eat at so that when you reach that GOAL, you are used to and continue to eat at that calorie/day. It will work and it is accurate however, the weight loss will be slow and many of us are not patient enough to do it that way.

When you enter your current weight as GOAL, it will generate what they call TDEE - total daily energy expenditure. THAT # is important as it tells you, taking into account your personal information, not only the minimum BMR to stay alive, but the amount of calories per day you need to MAINTAIN at the weight you are at RIGHT NOW.

The best way to lose weight a bit faster than the above with true GOAL weight AND still doing it at a healthy pace is to take that TDEE # from the chart that will generate and less out a % which will give you an accurate amount to eat per day to lose weight.

On the chart will be multiple lines describing activity levels - as much as I work at a desk job, I have used a pedometer for the large corporation I work in along with kids and shuffling all day and can log in 5-7K in steps per day. So appearances say pick "desk job" but much again has been discussed on the activity level and the one common thread and mistake people make at this critical calculation is underestimating their activity level.

If you say you work out 1 hour a day maybe 2-3 times a week at most and consider that "little exercise," what do you do with the other 23 hours in your day? You work, walk, run kids here and there, do chores around the house, etc.

So the mantra being said is unless you literally lay in bed all day every day, if you have little exercise but go to work and do other things that keep you moving in some way (even showering burns calories), everyone at the minimum should be selecting "light" activity or higher. So pick a truly accurate level and consider all the things you do all day.

So, let's do a real-life example:

my BMR is 1529 (I now know I must eat AT LEAST that per day minimum)

I work at a desk job but again, I walk easily 5-7K steps a day with work and kids, so I look at the "light" activity line

my TDEE right now at my current weight is 2116 - that is the "light" activity line # for my measurements, stats, body fat %, etc for my weight RIGHT NOW (which will change) - if I ate 2116 every day my body would stay at the same weight - this is what you would eat to not change your weight

but like many, I want to lose - I love the plant-strong health benefits for sure, but I do want to lose

what you do then is take your particular TDEE # (2116) from the chart and less out a %

the general rule of thumb is if you want to lose:

5-10 pounds, less out 10%
10-20 pounds, less out 15%
20 or more pounds, less out 20%

anything higher in % is really for people who have undergone gastric surgeries and going higher could potentially put your body back in that "nutrient-deficient" mode so 20% is about what most use as a healthy guide

now, 2116 x 20% would give me 423 - I deduct that 423 from 2116 and get:

1693

that 1693 is now my calories per day to eat that will not only maintain my BMR (which I know is 1529) but will also allow me to eat UNDER the 2116 TDEE for my weight right now - that concept is what they call "eat more to weigh less" and it goes contrary to what we all learned as far as losing weight - I am still learning to accept this as fact and EAT more.

So, now that has me eating 20% under 2116 to lose (1693) but ABOVE my BMR so that my body learns I am not starving it, that it should not "hoard" the calories and keep the fat and eventually the body will release the fat.

Many people looking to lose weight fall into this trap where they have eaten so little for so long that the body has to re-learn and reset the metabolism - in fact, some believe a true "reset" would be to eat at the TDEE # (2116) for 6 weeks or so and only THEN drop off a %.

Either way, knowing this exact # will surely get you to where you want to be - it's just that your body trying to survive may take a few weeks to understand you are not going to deprive it anymore and it CAN let go of the fat as it understands it will always be fed and nourished to the point it is not panicked and storing it all.............make sense?

Where I am personally is going into 6 weeks plant-strong (YAY!) and almost 2 weeks at my re-adjusted 1680 per day calorie - I did the 1200 and many days below that for those first few weeks so my body must re-learn.

I may have 4 weeks yet for my body to truly learn and let go of the fat and burn all the time. It is hard b/c you want it NOW but gaining weight took a while and so will lose it. In fact, some have a slight gain while the metabolism is resetting so be warned, do not panic, it means the body is changing the way you need it to change to burn fat.

The body just needs the time to re-learn so, for me, I will wait the 6 weeks if needed, keep eating whole food plant-based, ignoring the scale as much as I can, and wait - it WILL drop off - it is logic, the body must and will change and let go eventually.

Last note on TDEE, as you lose weight, maybe every 5-10 lbs, return to the site that gives you the calculations and reassess your TDEE as the more you lose, the more that # will change, and this way you are always eating right AT where you should and following the eating you need so you are never too far under and thwarting your body back into being nutrient deficient and stalled.

I have also noticed although I lost 13 lbs in about 5 weeks, the weight loss now is slower but I swear my shape is changing - dresses and pants fit that were too snug before, I see definition in my thigh and calf muscles that were not there - this is probably why if you can get away from the scale numbers, many take and rely only on measurements of their body and even if the scale is stalled or moves slowly, you are losing inches which means the body is starting to turn on and change and burn and create a much leaner version of you......