Why isn't my BMI going down?

mehs04
mehs04 Posts: 184
edited October 2 in Fitness and Exercise
I'm down more than 20 lbs since my highest weight back in January 2010, but 15 of those lbs have come off since June 23 when I started doing the 30 day shred. I'm losing inches, but nothing dramatic, 1.5" on my bust, and 2.5-3" each on my waist and hips. I've done the 30 day shred 6 days a week since starting at the end of June and today finished day 10 of my 3rd round of it (day 70 total). I use 3 lb weights.

On August 16 I started biking, too. I've been biking atleast 3x's/week since then, usually 4x's/week, but sometimes 5. As of today (Sept. 15), I've biked 145 miles (on the road).

I have a Tanita brand digital scale that I got for Christmas (I asked for it.) a few years ago. It shows weight to the tenth of a lb, % water, and % body fat. Since June, my body fat has only gone down about 1 - 1.5%. Sometimes it goes down another .5%, but then the next day it is back up that same .5%. I weigh myself in the morning right after I get up, after going to the bathroom, before eating or drinking anything.

Is it what I'm eating? I try to stay away from lots of processed foods. Breakfast is usually 2 eggs or 1 egg and some type of whole wheat grain food. Lunch is usually .5 - 1 c whole milk cottage cheese with 2 servings of fruit or a salad of 3-4 c romain lettuce, 1-2 carrots, 1 Tbsp extra virgin olive oil, and sometimes a bit (.25 - .5 c) of shredded cheese sprinkled on top. I try to eat a fruit or a veggie with homemade hummus or natural almonds for a snack. Supper is usually a meat with some type of veggie and a starch. I know I fall off the wagon sometimes and don't eat well, but when I am eating well, that's how I try to eat. Yes, I still do have a cookie or two or a little ice cream here and there, but I try not to do it much. I actually find that when I eat well, I don't crave those sweet things.

So, does anyone have any ideas why my body fat % doesn't seem to be decreasing? Any tips? Thanks in advance.

**Edited to add: I'm sorry. I'm using BMI and body fat % interchangably, and they aren't. I suppose I should have titled this "Why isn't my body fat % going down?" That's what my scale measures and the number that doesn't seem to be going down much at all. Sorry about the confusion! I try to make sure I eat atleast 1200 calories/day, and I often eat atleast half of the calories I've "earned" exercising.

Replies

  • hnpervert
    hnpervert Posts: 10
    BMI doesn't distinguish between muscle and fat. According to BMI, Tom Cruise is nearly obese.

    YOu're better off using callipers rather than scales to measure BF%, they're more accurate. And cheaper.
  • vanessaclarkgbr
    vanessaclarkgbr Posts: 731 Member
    BMI doesn't distinguish between muscle and fat. According to BMI, Tom Cruise is nearly obese.

    YOu're better off using callipers rather than scales to measure BF%, they're more accurate. And cheaper.

    Agree. My daughters ex was a body builder, and on a BMI scale he was obese. That said - I think what you're experiencing is 'normal' my main driver is BMI, and 26lb down it hasn't shifted much. That's a slow mover, the BMI number!
  • MissingMyOldSelf
    MissingMyOldSelf Posts: 689 Member
    BMI doesn't distinguish between muscle and fat. According to BMI, Tom Cruise is nearly obese.


    LOL doesn't help that he's what..... 5'5"? :)
  • Cytherea
    Cytherea Posts: 515 Member
    Well first of all, BMI and body fat percentage are two different things. If you lost weight, your BMI has definitely gone down.

    It sounds like maybe you aren't eating enough, especially with all that exercise, which would cause your body to hang onto the fat. Eating a few processed things here and there isn't gonna kill you. In fact, plenty of people lose weight without eating clean. So that isn't the problem. It is probably more an issue of AMOUNT than anything else.

    There is also the possibility that your scale just isn't all that accurate when it comes to calculating body fat percentages. *shrug*
  • dbgrl100
    dbgrl100 Posts: 13 Member
    BMI doesn't distinguish between muscle and fat. According to BMI, Tom Cruise is nearly obese.

    YOu're better off using callipers rather than scales to measure BF%, they're more accurate. And cheaper.

    I completely, 100% agree. BMI is useless when trying to determine fat. You shouldn;t worry about it, it's more a broad outline of the average weights of people with your height.
  • mleipe
    mleipe Posts: 54
    Maybe I'm missing something here, but if your weight is dropping your BMI should be dropping, too, unless you're getting taller.

    BMI is defined as: BMI = (W * 703) / (H * H)

    where W is your weight in pounds and H is your height in inches.
  • cPT_Helice
    cPT_Helice Posts: 403
    Your body fat % and BMI are two totally different things. BMI is based on a mathematical formula and is as follow:
    BMI = weight(lbs)/height(inches)squared x 703
    In words it is your weight in pounds divided by your height in inches squared. Multiply this by the metric conversion factor of 703.
    If your weight changes and your height does not, it is mathematically impossible for your BMI to not change.

    For example: If someone is 5' 7" and their initial weight is 170, their BMI is 170/67squared X 703 = 170 /4489 X 703 = 26.6 which would be overweight

    If that same person lost 20 pounds....... 150/4489 X 703 = 23.5 which is a healthy BMI

    As far as you body fat % not changing, it could be that your scale is not the best measurement or it could be that your ratio of fat to muscle is not changing. Based on what you explained, that shouldn't be the case but keep in mind that a 1% change is not a bad change. Average Body Fat % is around 25-30%. The fitter you are, the lower it will be, female athletes generally being preferably in the mid teens to -20% range, though you really don't want to get below 15 or 16% and that is even reserved the more elite athletes.

    I wouldn't worry too much, based on the scale, But, I am assuming that you are always taking the measurement before eating, drinking and working out (should mention that). There are other things to look at, such as waistline and hip to waist ratios, etc.

    Hope this helps some.
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