I have posted twice before on this:
Figuring Your Calories: Round 1
I've Got Some Explaining To Do: Round 2
I got a great email this morning that made me take a second, third, and twenty-seventh look at my calorie counting methods. I’ve explained before that I use my iPhone’s “Lose It” application to calculate and track my calories. I realize, however, that not everyone is using Lose It to calculate their calories, so I provided the Harris Benedict Method in order to figure your caloric needs.
I list in my Eat With Me posts that my lately BMR is around 1900 calories. Well, using the Harris Benedict Method, I have a BMR of 1414. Now, I know that there is a large range for counting calories, but this 500 discrepancy is just too large for me -- or this insightful reader -- to ignore. So, I dove into my iPhone this morning. I have emerged from the land of numbers and figures and have a few things to share.
First of all, I was surprised to learn that "Lose It" does not use the popular Harris Benedict Method that I recommended. It turns out there is a newer formula out there called the Mifflin Method that better represents our bodies and this more sedentary culture we are proud to be a part of. It also calculates our RMR - or resting metabolic rate. Here’s the difference:
BMR stands for Basal Metabolic Rate, and is synonymous with Basal Energy Expenditure or BEE. BMR measurements are typically taken in a darkened room upon waking after 8 hours of sleep; 12 hours of fasting to ensure that the digestive system is inactive; and with the subject resting in a reclining position.
RMR stands for Resting Metabolic Rate, and is synonymous with Resting Energy Expenditure or REE. RMR measurements are typically taken under less restricted conditions than BMR, and do not require that the subject spend the night sleeping in the test facility prior to testing.
Definitions taken from http://www.caloriesperhour.com/tutorial_BMR.php
OK, so "Lose It" uses the Mifflin Method. If you are interested, here it is:
For women: (10 x w) + (6.25 x h) - (5 x a) -161
w - weight in kg
h - height in cm
a- age
Alright, with my numbers plugged in, I got an RMR of 1,362 calories. OUCH! That’s even lower than the Harris Benedict Equation! Well, it turns out that Lose It then multiplies that by my PAL factor-- Personal Activity Level (see Step 2 here for the PAL factors). But, since they know with "Lose It" everyone is going to plug in their workout calories, they choose a lower PAL factor of 1.45.
So my RMR x PAL = my calorie budget. With my numbers it looks like this:
1362 x 1.45 = 1,975
That, allegedly, is just what I need to eat to maintain my weight. I also plug in my workout calories, then eat them back through out the day.
After getting this morning's email, however, and discovering that "Lose It" is using an automatic PAL factor of 1.45 for me, I feel that is a bit high for me. So, after much deliberation and calculating, I’m going to use a PAL factor of 1.3 instead -- more accurately reflecting my actual activity level when I am not exercising. Then, I will plug in my workout calories on top of that. My new numbers look closer to this:
1,362 x 1.3 =1,770 calories per day.
So, you will now see some changes in my calorie budget in my Eat With Me posts:
1,362 (RMR) x 1.3 (PAL) = total calories
- 500 (weight loss calories)
+workout calories
------------------------------------------
GRAND TOTAL!
Holy cow. I'm tired. I have a degree in Elementary Education, not rocket science. No wonder people go crazy when trying to lose weight. WE JUST WANT TO KNOW HOW MANY CALORIES TO EAT! OK, I'm done with my rant. I hope I've done more to clear things up, and not made you want to go eat some Double Stuffed Oreos. Please send any questions my way.
**Side Note: So, you may ask, which method do I prefer? The Harris Benedict Equation? The Mifflin Equation? Well, the totals are not that far part, so either one really. I will be using the Mifflin Equation since I'm still using Lose It. And the Harris Benedict has a tendency to overestimate caloric needs and I'm more of a underestimate kind of gal.
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