Calculating Metabolism (BMR)

by Rebecca Shaw
(Degraff, Ohio)

How do you figure my BMR (also know as "metabolism")?
Can you break it down for me?
I don't quite understand it. It's been explained to me several times but I need to visibly see it to comprehend.

I'm 42 years old. Ht = 5'6". Wt = 320 lb.

How do I figure:

  • Metabolism

  • Total energy needs

  • Body mass index

  • % of ideal body weight

  • How many grams of carb, protein, and fat I need every day

  • Water needs each day

I figure if I calculate it I can understand and perhaps calculate the rest of the family. So would you please help me to understand this.
Thanks a bunch.


Thanks for writing.

Feel free to utilize the interactive calculators on my website.

You'll be able to:

Calculate your metabolism (BMR).

Figure how many calories you can eat in a day (total energy needs).

Calculate body mass index (BMI).

Your ideal body weight (IBW) according to ht/wt charts is 130 lbs + - 10%. (Based on allowing 100 lbs. for the first 5 feet and 5 lbs. for every inch above 5 feet.) At 320 lb. that makes you 246% IBW.
(320lb./130 lb. x 100)

Water is a tricky one. In general, half your body weight in oz. is recommended.
320 lb / 2 = 160 oz. (this equals 20 cups... or just a little more than a gallon/day!)
However, depending on the climate you live in and your activity level, this can vary.
The BEST way to gauge if you are getting enough water is to look at the concentration of your pee.
YES...I said look at your pee!
Your pee SHOULD be pretty pale looking. If it's dark (concentrated looking) you need to drink more water!

Your carb, protein, and fat requirements are individual. They are based on how many calories you are eating, your activity level, health concerns, etc. In general, you can figure you need:

  • 50% calories from carb

  • 20% calories from protein

  • 30% calories from fat

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