BMI - Body Mass Index

As I get closer to my goal, I am finding myself more and more interested in knowing my actual body fat percentage. Initially, I was all for the weight loss being measure by the numbers on the scale. Then, I because interested in the inches lost around my hips, waist, thighs, biceps, etc. Now, I kind of want to know if I am really lowering the fat, while keeping most of my muscle.
So, how do I find that out, I wondered?

Well, the first of my goals was to get my weight down into a healthy weight range as indicated by the BMI (Body Mass Index) chart below.
GREEN is Healthy Weight. YELLOW is Overweight. RED is Obese.
I am 5'1" and I am 132.5 pounds...ALMOST to 130, which will put me in the healthy weight range! (Actually 132 will get me there, but either way...the medical community will soon consider me to be at a healthy weight.) I started my weight loss quest at 164 pounds...I was actually considered to be obese then...that boggles my mind.


What is the History of the BMI chart?
Well, about 10 years ago, NIH (National Institutes of Health) released its new healthy weight guidelines. The purpose was to find a uniform method that the medical community, insurance companies and the general public could use to measure body fat and healthy weight. One interesting thing that happened back then is that they actually lowered the overweight threshold from a score of 27.5 to 25. That meant that quite a few people who were once considered to be at a healthy weight range were suddenly overweight. There are quite a few BMI calculators and charts online to help determine your BMI score quickly and easily.

How accurate is it?
The chart is best used as a screening tool - not as a definitive calculation of your body fat percentage or your overall health. One of the reasons for this is that it does not account for a person's age, gender or the amount of muscle mass they have. Football players, for instance, might score high on the BMI chart when really their fat percentage is low. It's the weight of their muscle that skews the results for them.

So, the BMI chart may be a starting point for a person or a medical provider in trying to determine a person's health weight and body mass, but there are better ways to test for actual body fat. For me, once I get myself into the healthy zone, I am going to look into getting tested for my actual body fat percentage (probably via a skin-fold measurement test.) They sell calipers online and if used properly, I should be able to get a very accurate idea of my fat loss success.

HEALTHY LINKS

1. WebMD - BMI information.
2. BMI calculator
   
3. TopEndSports.com - Information about the Skin Fold Measurement test for body fat.
4. Accu-Measure Fitness - Purchase calipers to measure body fat
   

Calculations: Part 3

I know my Maintenance Calories...now what?
Well, this is the final step in your calculations.
You now know how many calories you need to eat in order to maintain the same weight.
I calculated that number to be 1942.
If I eat 1,942 calories, my body will use all those calories to fuel all of its bodily functions and all of the activities I perform. It won't need to use any of my fat stores or muscle stores because I gave it all the food fuel it needs. That is great if you are at a healthy goal weight...but if I want to lose weight, I need to eat below my maintenance level. I need to give myself a deficit every day.

If, for instance, I eat only 1500 calories a day, my body will use that 1500 to fuel itself, but because it burns 1942, it needs more than that. So it will then begin to use our fat (and muscle) stores to make up for the missing calories.
This is how we lose weight.

Just remember that it is important to choose a healthy, safe and steady deficit that will promote weight loss without harming our body.


How did I decide on my weekly weight loss goal/my deficit?
The general rule of thumb is to shoot for either 20% below your maintenance number or to try to lose only 1% of your body weight per week. Both of these options seem to provide a person with a safe and steady weight loss.

I chose the latter option because it gave me a larger deficit, while still keeping me above my BMR (which I think is really important. The body should at least get enough fuel for its basic bodily functions!)
So, one percent (1%) of my body weight is 1.3. I rounded that number down to 1 and made that my goal. I want to lose 1 pound a week.

I won't go into to much detail here about choosing a goal that brings about too rapid a weight loss. I'll just say that I personally think it is usually unnecessary, unhealthy, and counterproductive in the end. Always discuss with your doctor if you are planning a diet that severely restricts your calories.

Again, I think never going below my BMR is the rule of thumb I use.

How do I lose 1 pound of fat a week? What is my exact deficit?
To lose 1 pound of fat a week I need to consume 500 calories fewer than my maintenance calories per day.

One pound of fat = 3500 calories.
3500 divided by 7 days (in a week) = 500 calories a day.

This means that I have to have a 500 calorie deficit every day and by the end of the week...voila!..I have lost a pound. (In a perfect world, of course!)

The next step is to then take my Maintenance Calories and subtract the 500 deficit from it in order to get my Calorie Goal for weight loss. This will give me how many calories I can consume every day in order to lose 1 pound a week.

So what is my calorie goal?
My Maintenance Calories were 1942.
My deficit is 500.
That makes my Daily Calorie Goal: 1442.

This is the number of calories I can eat each and every day to lose 1 pound a week. We already know that my body needs 1942.
Well, I am only going to give it 1442.
The rest is up to my body...it must fend for itself.
It must start converting my fat stores into energy to make up for the missing calories.

And, so begins the road to my slow and steady, healthy and happy, weight loss!

Is there an easier way to do this? Without calculations on paper?
Sure!
Here are some links to some online Calorie Goal calculators. Unlike the calculators in my previous post, these do more than just calculate your BMR/RMR. They do the whole thing! Just put in your stats and you are given a calorie goal to lose weight!

HEALTHY LINKS

FreeDieting.com - This one is my favorite. You can use the advanced options to switch between a calorie goal based on the Mifflin-St.Jeor or Harris Benedict or lean body mass.
You can also test out their zig-zag calorie tool for those who like to "calorie shift" or "calorie cycle" or "zig-zag diet!"

Diet-Blog.com - this site gives you a nice calorie range. Based on the Mifflin-St.Jeor equation.

That's all!

Calculations: Part 1

I am a sucker for those online calorie calculators. Every time I come across a site with one, I use it. I don't know if I am looking for confirmation that I am using the right calorie goals or if I'm just a numbers nerd.

In any case, due to the fact that I lose weight by tracking calories, the right calorie intake numbers are important to me. I try to get as accurate a calculation as possible.

To find my daily calorie intake number I can go the short way and use an online calculator (I have some links at the bottom of my "Calculations: Part 3" post) or I can do it the long way:

Step One: Calculate my BMR/RMR.
Step Two: Multiply that number by an activity multiplier to get my Maintenance Calories.
Step Three: Subtract a deficit from my Maintenance Calories to get my Daily Calorie Goal.
Step Four: Eat, exercise and stay as close to my Calorie Goal as possible!

This post will cover Step One.

What is the BMR and RMR?
BMR stands for Basic Metabolic Rate. RMR is my Resting Metabolic Rate.

Basically, my BMR or RMR estimates the amount of calories my body will burn while at rest. If I were to lie in bed all day (no getting up, no moving around...) I would burn a certain number of calories. That number is represented by my BMR/RMR.
The chart below will give you an estimated breakdown of my daily caloric burn:

60-70% - Basic bodily functions (...breathing, temperature regulation, etc.) as represented by my BMR or RMR.
15-30% - All physical activity (walking, running, cooking dinner, chewing gum, tapping my toes...anything other than lying in bed all day.)
10% - Thermic effect of food. (Calories burned through the digestion, asborption and storage of food.)

What is the difference between the two terms BMR/RMR?
These terms are often used interchangeably and the difference between the two is relatively minor.
The difference basically comes from the fact that each rate is clinically measured under two different types of conditions. To get a subject's BMR, he or she must be in a fasted state (so that digestion calories do not play a part in the calculation) and the subject must be in a state of complete rest and in dark, quiet surroundings. It basically just tests how much you burn through regular biological functions.

The test for a person's RMR is not as strict. The subject must be resting, but the calculations can include a some physical disturbance and possibly some digestion. This goes above and beyond BMR testing and includes any additional minor activity that occurs during a rested state.

In any case, we really don't have to worry about any that and we can simply find our estimated BMR or RMR by using an online calculator or by using the equations I will provide below.

What type of BMR/RMR forumlas are available?
Currently there are two popular math formulas to use in order to figure out a person's BMR or RMR. These two formulas are the Harris Benedict Equation and the Mifflin-St.Jeor Equation.
(Note: There is also a way to determine your caloric intake number by lean body mass called the Katch-McArdle formula. However, most people - including myself - do not know their lean body mass, so I won't talk about that method.)

I don't like math. Where are some good online BMR/RMR calculators?
The links below will bring you to two online BMR/RMR calculators:

BMR Calculator (uses the Harris-Benedict Equation)
My Fitness Pal (uses the Mifflin-St.Jeor Equation)

Which do I personally use and why?
I currently use the Mifflin-St.Jeor formula.

While the Harris-Benedict formula is more popular, it has been tested and reported to be slightly more inaccurate than the Mifflin formula. The Harris-Benedict numbers tend to be slightly overestimated (meaning you might be eating more than you should!)

However, some people have great success using Harris-Benedict and many of the popular dieting sites use that formula for their calorie calculations, so it really is up to you to test the numbers and figure out which works best for you.

Just a quick note....it appears that many times a site will use the Mifflin-St.Jeor equation and call the result your "RMR" and then use the Harris-Benedict equation to get a person's "BMR."
Other sites may use both formulas and call both results your "BMR". Don't let that confuse you. They are really talking about the same thing and the most important thing is the number you get from using either formula.

I like math! How do I calculated my BMR/RMR on my own?
First, you need to convert your weight and height into kilograms and centimeters.

This is done by:

Dividing your weight (in pounds) by 2.2.
Multiply your height (in inches) by 2.54.

Example:

A 33-year-old female. You weigh 134 and I am 5'1" (or 61 inches).
134lbs. divided by 2.2 = 60.9 kilograms
61 inches multiplied by 2.54 = 154.9 centimeters

Now, you take those numbers and plug them into one or both of the formulas below.

-------------------------------
* Mifflin-St Jeor Equation *

Men: RMR = (9.99 X weight) + (6.25 X height) – (4.92 X age) + 5
Women: RMR = (9.99 X weight) + (6.25 X height) – (4.92 X age) – 161

Example:
A 33-year-old female. You weigh 134 and I am 5'1" (or 61 inches).
134lbs. divided by 2.2 = 60.9 kilograms
61 inches multiplied by 2.54 = 154.9 centimeters

(9.99 X 60.9) + (6.25 X 154.9) - (4.92 X 33) - 161 =
608.39 + 968.13 - 162.36 - 161 =
1253.16

My BMR/RMR = 1253
So, according to the Mifflin-St.Jeor forumla, these are how many calories you would burn just by lying in bed all day long.

-------------------------------
*Harris-Benedict Formula*

Men
66.5 + (13.75 X weight in kg) + (5.003 X height in cm) - (6.775 X age in years)
Women
655.1 + (9.563 X weight in kg) + (1.85 X height in cm) - (4.676 X age in years)

Example:
A 33-year-old female. You weigh 134 and I am 5'1" (or 61 inches).
134lbs. divided by 2.2 = 60.9 kilograms
61 inches multiplied by 2.54 = 154.9 centimeters

655.1 + (9.563 X 60.9) + (1.85 X 154.9) - (4.676 X 33) =
655.1 + 582.39 + 286.57 - 154.31 =
1369.75

My BMR/RMR = 1370
According to the Harris-Benedict formula, these are how many calories you would burn just by lying in bed all day long.

-------------------------------
Results:

Mifflin-St.Jeor = 1253
Harris Benedict = 1370

Two different equations...two different results.
It's up to each person as to which formula they want to use.

Okay I used the calculator (or did the math.) What happens now?
I now have my BMR/RMR.
Remember this number only accounts for some of the calories we burn each day (about 60-70%). We need to find an estimate of all the calories our bodies burn each day.
This means you have to add youractivity calories, too. That is the only way you can get the best estimate of the total number of calories your body needs every day.

I will explain this next step in the post called "Calculations: Part 2". This is where I calculate in activity levels to find Maintenance Calories.

Note: Remember, there are online calculators to do all of this for us, but some people like to see where the numbers come from, which is why I am explaining it all here.

FAQs

Who are you?
I'm Jen!

What is the purpose of this blog?
Since starting my current journey to lose weight I began collecting a lot of healthy information and tips along the way. I put the information into notebooks, saved them to my computer, printed charts, etc. I finally decided to gather it all together and organize them in one place...Blogger! It just makes it easier for me to have everything in one place.

Because I am still learning and still researching, some of the information may not be complete. This is why I definitely welcome any visitors to share their knowledge, experience...and even correct me on any misinformation I may have gathered.
I am definitely not an expert. I'm just someone who thrives to know everything I can about topics that interest me.

I will also use this blog to track my daily/weekly/monthly progress to my goal weight...and to my life beyond the weight loss.
I am tired of being tired.
I am tired of losing weight. I look forward to getting to my healthy weight and staying there forever - with lifelong energy (...or JENergy!) and good health.

So, how am I currently losing weight?
I am counting calories - food calories and exercise calories. Plain and simple.

What tools do I use to count calories?

• The Daily Plate - an awesome web site for tracking food and exercise.
• A generic food scale. Soon to be this one.
  
• Polar 6 Heart Rate Monitor
• FreeDieting.com - to calculate my calorie goals.
• Nutrition Data.com - I use their search engine to get food information and for estimated glycemic index ratings for the food I eat.
• A bathroom scale for daily weigh-ins. (Soon to be upgraded to a Tanita Digital scale.)
• Burn The Fat, Feed the Muscle e-book. I love the information in here. I have read this a lot and I incorporate so much of it into my diet.
• The Hacker's Diet. I use this web site to record my daily weigh-ins. It keeps track of my weight loss trends and my weekly deficits based on my weight. I find it so much better at giving me a larger picture of my weight loss and whether I am actually on a losing trend or a gaining trend.
  

What are some of the basic things I do to lose weight and stay healthy?

*I try to lose 1% of my bodyweight per week. (EX: If I weigh 150, I try to lose 1.5 pounds per week.)
* I base my calorie intake on the Mifflin-St.Jeor equation.
*My food choices are based on the Low-Glycemic Index/Load lists.
*I eat 5-6 meals a day - every 3 hours or so.
*I exercise 30-45 minutes 4 to 5 times/week.
*Strength train 2-3 times a week.
*My macronutrient ratio is : 40-50% Carbs, 25-35% Protein and 20-30% Fat. (Usually 45-30-25)
*Sodium under 2500 mg every day.
*Protein with every meal.
*Cup of white tea every day.
*A MUFA (monounsaturated fat) serving with my 3 main meals.
*Attempt a 2:1 ratio of Carbohydrates to Protein at every meal. (EX: 30 grams of carbs to 15 grams of protein)
*80-96 ounces of water every day. (5 or 6 of those 16oz water bottles)

My Weight Chart: