Low BMI

NadNight
NadNight Posts: 794 Member
in Goal: Gaining Weight and Body Building
A lot of people (myself included) take bmi with a pinch of salt and often the issue is that people with higher muscle mass have a high bmi that would suggest they were overweight when in fact they're perfectly healthy just with more muscle. But what about when your bmi says you're underweight? I have a bmi of 17.6 which is underweight yet I don't feel or think I look unhealthy or even skinny. Do I need to gain weight or just trust my own judgement?

Replies

  • PPumpItUp
    PPumpItUp Posts: 208 Member
    There is a body fat percent you should not go under because some fat is necessary for biological functions. For women I think it is 10ish percent. Do you have a healthy lean body mass?
  • BrianKMcFalls
    BrianKMcFalls Posts: 190 Member
    How you feel is the most important thing. I grew up skinny, it was just my build. If you feel good about your body and your doctor doesn't have any concerns with your health related to it, it's just a number. Plenty of unhealthy people with normal BMIs and vise versa.
  • NadNight
    NadNight Posts: 794 Member
    I've never had my body fat percentage measured. Using a not very scientific method of looking at a picture of women at different body fat percentages and comparing to a picture of myself, I think I look in the 20-25% range. I did actually post a question on one of these boards the other day asking about the best way to work out body fat percentage but the answers that came back were 'go to the doctors' as online calculators etc aren't accurate. Some of those calculators use about 10 different measurements, others just go off height, weight and waist. I think the picture way might even be better!
  • T0M_K
    T0M_K Posts: 7,526 Member
    according to your pictures, you don't appear underweight. you may want to add weight lifting and put on some lean muscle. :)
  • PPumpItUp
    PPumpItUp Posts: 208 Member
    NadNight wrote: »
    I've never had my body fat percentage measured. Using a not very scientific method of looking at a picture of women at different body fat percentages and comparing to a picture of myself, I think I look in the 20-25% range. I did actually post a question on one of these boards the other day asking about the best way to work out body fat percentage but the answers that came back were 'go to the doctors' as online calculators etc aren't accurate. Some of those calculators use about 10 different measurements, others just go off height, weight and waist. I think the picture way might even be better!

    Do you have a Complete Nutrition close to you? Their stores have a pretty good bioelectrical impedance machine that they claim to be almost as accurate as a dexa scan.

    There are scales with bioelectrical impedance built into them but they are as accurate.

    You can get a body fat caliper and do a pinch test. A lot of gyms have trainers that will do the pinch test for you.
  • mom23mangos
    mom23mangos Posts: 3,070 Member
    I think if you aren't having any medical issues - no fatigue, hair falling out, missed periods, etc. then you should be fine.
  • PPumpItUp
    PPumpItUp Posts: 208 Member
    * the scales aren't as accurate
  • singingflutelady
    singingflutelady Posts: 8,736 Member
    You should at least maintain. I'm assuming you have changed your goals as your profile says you are trying to lose weight?
  • NadNight
    NadNight Posts: 794 Member
    singingflutelady wrote: »
    You should at least maintain. I'm assuming you have changed your goals as your profile says you are trying to lose weight?

    I'm re-evaluating at the moment and deciding what to do now I've reached my original goal
  • psuLemon
    psuLemon Posts: 38,389 MFP Moderator
    NadNight wrote: »
    A lot of people (myself included) take bmi with a pinch of salt and often the issue is that people with higher muscle mass have a high bmi that would suggest they were overweight when in fact they're perfectly healthy just with more muscle. But what about when your bmi says you're underweight? I have a bmi of 17.6 which is underweight yet I don't feel or think I look unhealthy or even skinny. Do I need to gain weight or just trust my own judgement?

    Regarding the bold, those are the exception and not very common and more often, take years to get to that point. I don't actually put much faith in BMI. I do put more faith in body fat and blood work. Ultimately, if you want, you could gain some more muscle to put you in a good range of BMI if you have concern.
  • amtyrell
    amtyrell Posts: 1,449 Member
    I think you should consult your doctor. Ask her or him for advice as they know your health and can see you in person. Trust what they say not some internet folks lacking all the info.
  • trigden1991
    trigden1991 Posts: 4,658 Member
    psuLemon wrote: »
    NadNight wrote: »
    A lot of people (myself included) take bmi with a pinch of salt and often the issue is that people with higher muscle mass have a high bmi that would suggest they were overweight when in fact they're perfectly healthy just with more muscle. But what about when your bmi says you're underweight? I have a bmi of 17.6 which is underweight yet I don't feel or think I look unhealthy or even skinny. Do I need to gain weight or just trust my own judgement?

    Regarding the bold, those are the exception and not very common and more often, take years to get to that point. I don't actually put much faith in BMI. I do put more faith in body fat and blood work. Ultimately, if you want, you could gain some more muscle to put you in a good range of BMI if you have concern.

    As one of those "exceptions" I agree. I go by the mirror, bodyfat percentage and health checks at the doctors to determine where I should be and how healthy I am.
  • JeromeBarry1
    JeromeBarry1 Posts: 10,182 Member
    You're a woman. When a woman's body fat percentage falls to dangerously low levels, her menses stops. So, if you have your monthly event, you have monthly affirmation that your body fat is in good order.
  • jseams1234
    jseams1234 Posts: 1,216 Member
    NadNight wrote: »
    singingflutelady wrote: »
    You should at least maintain. I'm assuming you have changed your goals as your profile says you are trying to lose weight?

    I'm re-evaluating at the moment and deciding what to do now I've reached my original goal

    I'm a little confused. You say you have reached your goal and state this in your profile - "A student looking to develop a healthy lifestyle and slimmer body :)"

    Your goal was a BMI of 17.6? I'd have to be at 130 pounds at 6'1 to be at your BMI. I did look at your second set of pics - is that a before or after? You are painfully thin - especially in the upper body in that set of bikini pics. The legs look normal. If this was a "before" pic what do you look like now?
  • new_arc87
    new_arc87 Posts: 38 Member
    I'm in the same boat - well, used to be anyway - due to a naturally thin frame. So I wouldn't worry about it if you look and feel healthy.
  • mekabr84
    mekabr84 Posts: 5 Member
    There are issues with the BMI scale. One of the issues is that it is increasingly inaccurate at the high and low ends of the HEIGHT spectrum. Are you pretty short? Then you can ignore the BMI, as long as you are still getting your period and you don't have people in your life saying you look sickly skinny.

    I'm 5'1". At my lightest, I had a BMI of 17.4. I was feeling well, monthly period, eating huge catered lunches every day at work, then making big dinners at home, then drinking a beer. I had a job that kept me on my feet all day, and I was walking and using public transport. Felt great, though people who had known me all my life thought I looked too skinny. People who hadn't didn't notice anything unhealthy-looking about my appearance, though.

    When I was at my very fittest (high school), I was eating 3 large meals per day, but also worked out a lot and had some nice muscle. Looked fantastic. Would have still looked great a couple pounds lighter (Mom was cooking for me, how could I refuse?). BMI was 18.5, the very lowest acceptable number on the BMI scale.

    When I was sitting around on the couch working online for a year, not getting enough exercise, eating all day, I had a BMI of 19.8.

    For my height, a BMI of 17.6 is equivalent to 93 pounds. That is the weight I hit if I'm eating well, doing doing a ton of walking all day, but not doing any special kind of exercise (as in, low on muscle). I personally think I look better a little heavier, even just 2-4 pounds, which make a big difference at this height. If you are shorter than me, then don't even worry about it the BMI thing. If you're taller, then you probably went a wee bit too far. If you're my height, you'll look better with a bit more weight, preferably muscle.
  • Tabbycat00
    Tabbycat00 Posts: 146 Member
    I technically have an "underweight" bmi (17.7) but everything functions fine. Blood work is good, ran a marathon, had a baby, hit middle age...still have a bmi of 17.7. I think it's just the way some of us are made. I wouldn't worry.
  • singingflutelady
    singingflutelady Posts: 8,736 Member
    Tabbycat00 wrote: »
    I technically have an "underweight" bmi (17.7) but everything functions fine. Blood work is good, ran a marathon, had a baby, hit middle age...still have a bmi of 17.7. I think it's just the way some of us are made. I wouldn't worry.

    She's trying to lose more weight....
  • kimny72
    kimny72 Posts: 16,013 Member
    OP, the only problem with going by "how you feel" is that some people have body dysmorphia - they don't see themselves as they actually are. If you are below what is normally considered a healthy BMI, I would schedule a physical. Your doctor can run some blood work and discuss with you what to look out for that might be a warning sign that your weight is a health issue.

    Outliers who don't fit the typical BMI guidelines are rather rare, and the issues with BMI are more often associated with being too heavy only because of exceptional muscle mass. If you are underweight, you either have very low body fat or very low muscle mass. Neither is really good for you over the long haul. So get that physical to determine whether you are in fact underweight or not, and go from there.

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