BMI, BMR, I just want to BLessOfMe

[Squid56]

I know that most folks discard the idea of BMI (body mass index) as a useful or relevant tool in determining your end goal for weight. I understand why, given that it's only inputs are height and weight, the generalization that it makes is to wide to be useful.

However, most people seem to think that calculating your daily caloric intake using BMR + maintenance levels is ok, but BMR is calculated on age, weight, height and sex (a few more inputs than BMI, but not by much).

So let's make this personal. I'm 5'10" and 216 lbs right now, 40 yrs old and male. My current weight loss target is 185 lbs.

According to http://www.nhlbi.nih.gov/guidelines/obesity/bmi_tbl.htm, at 5'10", 185 lbs, my BMI is 26.5 which is still in the "overweight" category. I'm willing to toss this out, I think I will be ecstatic to hit 185 and I don't care what the stupid chart says.

Moving on to figuring daily caloric intake. http://www.bmi-calculator.net/bmr-calculator/ tells me my BMR is 2029; add in the Harris-Benedict multiplier for moderately active (1.55) and I get a base maintenance 3145. I've been restricting my diet to 1500 - 1700 calories per day, and now I'm afraid my body's been in starvation mode and I've been hindering my actual weight loss for several months. So are these numbers realistic? BMR doesn't seem to be based on much more than BMI and most people discount that. Should I really be trying to consume 2100 good calories per day? I'm not sure I can get that much good food in me.

Finally, to address the "I want to be 185 lbs" issue. I know in general it's not the best idea to set a hard weight loss goal, but I'm looking to renew my life insurance with a different provider than I'm currently with. This comes with a requirement of a full medical checkup, and on the providers site, you can get rough quotes on your monthly payments by simply entering height, age and weight, and by varying the weight, it's amazing how much your monthly premium can be lowered. So that's why I have my target where it is.

So chime in and give me my druthers, and I will thank you in advance.

[Waltron]

My advice: don't get too caught up in the numbers, focus on getting fit.

[msuroo]

Firstly, I would be careful about using the "moderately active" multiplier in your TDEE calc unless your actual daily routine is quite active. A lot of desk jockeys see "moderate exercise 3-5 times per week" and think hey, I'm moderately active! (I was guilty of this myself.) Look at the calc results a little closer though - based on the inputs you've given, moderately active is like 700 more per day then sedentary. That's 4900 calories per week. That's a whole lot of calories to be burning doing moderate exercise 3-5 times per week. (Hell, I'm training for a marathon right now and not running 49 miles per week.) Assuming you work a normal desk job, you are much better off using the sedentary number as a baseline, and just treat any exercise you do as "negative" calories. You are never going to know exactly how many calories you burn in a workout session, so approximations are fine. Mostly because...

Those calculators are just a baseline. The thing that none of them say (that all of them should) is - track your progress and adjust as necessary. This is why it's OK that they are based on BMI inputs. Even if they had more complexity to them (like the Katch-McArdle formula based on BF%) - it's still just an estimate because everyone reacts differently. You have to track your progress for a while (at least a few weeks) and see what happens.

All that said, 1500 -1700 calories a day is probably a little light.

[Waldo]

You calculation is simply a calculation of an estimate.

If you want to calculate the REAL number for you:

Non-exercise Maintenence Calorie Burn = Calories In - Calories Burned Through Exercise - (Weight Change)*3500

Average this over a period of time to get a good number for your actual metabolism (it changes over time), so that you can set calorie targets that will cause results that are precisely what you expect.

For example:

Over a 2 week time

You eat 42,000 calories

Over that time you burn 10,500 calories exercising

And you lose 2 lbs

Your non-exercise daily maintenence calorie burn is (42,000-10,500-(-2*3500))/14 = 2750 calories per day

A daily NET (calories in - exercise calories) of 2250 will cause 1 lb/wk loss, 1750 will cause 2 lb/wk loss, 3250 will cause 1 lb/wk gain.

This number jumps all over day to day. Even weekly it can vary quite a bit, but over 2 week or longer time spans it is pretty stable, enough so that you should be able to set calorie goals that will cause gain or loss at almost exactly the rate you set.

[msuroo]

And if you're meticulous like Waldo, you come out with a bunch of awesome graphs like this (and amazing results to boot).

[Razor]

Really, I wouldn't get caught up in counting calories and such until you've actually plateaued on your weight loss.

If you follow a good exercise regimen and eat HEALTHY, (i.e. no sodas, processed foods, fat heavy dairy products or anything very calory dense). You will feel much better and lose weight. Then, if you've noticed you've stopped losing weight and just stayed at the same weight, counting calories is the next step. Lots of people I know who changed their diet, including basically my entire family, focused more on counting calories than exercising and eating quality food. Then it got to be too much of a hassle, because nobody with a life can count every single meal (I know I can't), and they stopped again. Personally I tried counting calories (Mind you, I'm trying to eat on a surplus), and it just wasn't pleasant at all entering in every little thing I ate, and then at the end of the day forcing myself to eat more because I didn't hit a macro. I can only imagine the frustration of eating TOO much that day and not being able to do anything about it, and just adding to the frustration of calorie counting. So I'd say don't do it until you actually feel that you have to.

Also, in terms of goals, I would say don't make a certain weight or BMI your goal, but a certain body fat percentage. BF% has much more to do with health than total fat or total weight.

[Waldo]

Then it got to be too much of a hassle, because nobody with a life can count every single meal (I know I can't), and they stopped again. Personally I tried counting calories (Mind you, I'm trying to eat on a surplus), and it just wasn't pleasant at all entering in every little thing I ate, and then at the end of the day forcing myself to eat more because I didn't hit a macro. I can only imagine the frustration of eating TOO much that day and not being able to do anything about it, and just adding to the frustration of calorie counting.

Oh the torture of a minute or two of work on the tricorder entering in the day's meals.

If you are in a surplus and it forced you to eat more, than it did what it was supposed to do. Likewise if you are in a deficit and don't have calorie room, you think twice about the snack. It is only frustrating if you let the food own you. What is frustrating to one is empowering to another. It allows you to control the situation.

[Silvergamma]

I've been calorie counting for two years, and I don't find it arduous at all. Smartphones and apps are awesome (who knew, right?).

Waldo's advice is really good, and will give you the most accurate information.

If you want something right now to go off, I would also recommend checking out the "Fat 2 Fit Radio" podcasts. They are currently on hiatus, but their BMR/calorie goal calculator is one of the better ones I've seen.

http://www.fat2fitradio.com/tools/bmr/

I would agree that 1500-1700 is probably a little low for you. I've been in a similar situation. I worked on bumping my calories up in increments of 100/day, and would sustain that for a week to two weeks, before increasing again if needed. Without knowing exactly what you are eating or what you are doing for exercise, I would say 2,000-2,200 would be a good starting place. Ultimately, you want to find the caloric intake that your body is going to require at your goal weight and eat at that level. It's a little slower loss, but when you get to your goal there isn't a transition. You've already trained yourself to eat like the thin, healthy person that you want to be.

[Squid56]

Thank you all for the replies. I will continue with my efforts and hopefully continue to see improvements. I do count my calories, but not very strictly, I tend to just add 'em up at the end of the day in my head. If I do hit a plateau, I will be more vigilant. Interestingly enough, I've hit two small ones already, one at 234 and one at 224. Both lasted about 3 weeks and both were plateaus I was at going up the scale as well, so I expect that was a little body memory going on there. Waldo, your dedication is pretty amazing and being able to produce such intricate charting as data mining is a great experiment, wow!

My main concern was just that I might have been doing more harm than good at the 1700 calorie level given the recommended calorie estimate from the site, so I will do as instructed and add a couple hundred more per day and see where I'm at in three weeks. I'm keeping a battle log with my workouts if anyone has any interest there as well.

Thanks again, all.

[Tanktimus the Encourager]

Calorie counting works for me, but the BMI was created by Federal government drones who arbitraily picked nummers and apparently think skeleton's are healthy. Yesterday I googled calorie calculators, and the numbers I got for my weight loss goals varied by as much as (No-creative uphemism for fecal matter) 2000 calories per day. Loseit.com works pretty well for me and seems realistic based on weight loss, it also lets you enter your exercise for the day and adjusts your calories allowed in real time.

[aj_rock]

When you hit a plateau, try bumping the calories back up for a week, then drop them again. Your body needs a break from eating itself once in a while

[msuroo]

BMI was created by Federal government drones who arbitraily picked nummers and apparently think skeleton's are healthy.

Oh come on. BMI was only ever designed to approximate bodyfat percentages (and thus obesity rates) of entire populations - and at that it does a decent job. Healthy weight BMI ranges from 18.5 to 25. As a proxy for BF%, that's hardly a "skeleton".

There are much better ways of approximating the BF% of an individual person, so BMI does fall short in that regard - but that was never what it was designed for anyway. Just because people misuse it that way doesn't make it a worthless metric.

[Tanktimus the Encourager]

Oh come on. BMI was only ever designed to approximate bodyfat percentages (and thus obesity rates) of entire populations - and at that it does a decent job. Healthy weight BMI ranges from 18.5 to 25. As a proxy for BF%, that's hardly a "skeleton".

There are much better ways of approximating the BF% of an individual person, so BMI does fall short in that regard - but that was never what it was designed for anyway. Just because people misuse it that way doesn't make it a worthless metric.

Ok, in all fairness I just looked it up and my target weight is exactly 3.5 pounds under the cutoff between normal and overweight. I stand corrected.

[Avistew]

Still, if I do remember correctly, originally the cutoff between "normal" and "underweight" was at 20, and they lowered it to 18.5 to adapt to the people wanting to be thinner. So the idea that it's biased towards thinner people might have something behind it.

Still, it's mostly useless, but it can be a starting point if you can't measure your BF%. I'd couple it with a waist-to-hip ratio, since that's also easy to measure, until you can get a set of calipers or professional measurement of your BF%.

[spezzy]

there are BMR formulas that take Ito consideration bf%.

I'm not getting into the bmi or not discussion

[Kirkor]

Most people need to weigh a lot less then they think to be ripped.

re: BMR calcs, I've had a lot of friends who have had good luck by *not* using the activity multiplier at all --- this helps keep you from fudging the numbers due to subconscious ego issues, and just for those times when things aren't as tight as they should be.

I definitely would keep a food log and do the math for a couple weeks, otherwise you really are just flying blind.