How do they determine what is healthy or not? At my age, mine is now 20, which says normal.
When I graduated school. my bmi was 15.5
This says way too low yet I was completely healthy and ate a lot.
BMI is only useful for evaluating large groups. Individual results vary widely. Get your bodyfat levels tested, it’s far more accurate.
As an example, I am 5-8, 190lbs BMI 28.9. 30 is obese.Bodyfat for obese is about 25-30% My bodyfat percentage is 12%
BMI calculator.
What did you weigh/how tall were you, when your BMI was 15.5?
body fat is the only way to go. You can get it tested, there are also bathroom scales that will test it, though I honestly don’t know how accurate they are. Guys should be around… I forget, maybe 10-15% is within healthy range? Women are supposed to be a bit higher, like 20-25%. I’m just guessing at those numbers, though.
But yea, BMI is pretty useless, it doesn’t take into account the fact that muscle weighs more than fat, or that people have naturally different body types. Almost all professional atheletes are Obese by BMI standards, as is pretty much anyone who lifts weights regularly. When I was in the best shape of my life (doing two martial arts, fencing, and playing soccer, at least one of the above 4 every day) I was at something like a 26.5, still techincally overweight (I’m a point higher, now, hehe)
Yeah, seriously. I could stand to lose 25 pounds of fat, but in doing so I’d put on about 5 pounds of muscle. At 5’11, even 225 would be obese, giving me a BMI of 31.4, according to pat’s calculator. I may be technically obese now, but I’m classified at borderline morbidly obese (35, I’m at 34.2) according to BMI. Like pat said, it’s useful for large groups of people; as most guys my height and weight aren’t as fit as me. I’d venture to say it’s accurate for 95% of the population, though (that’s 3 standard deviations, right?).
I was involved in studies with the U of Chicago and those body fat scales and calipers and the devices the gyms use are WAY off.
The only way to get a real accurate measure is the tank. The dunk you in a tank of water while measuring you.
The OP says her body fat was low but she was healthy, well no you weren’t if you’re BMI was off. It’s like saying I have high blood pressure but I’m healthy. Well no you’re not.
You may be OTHERWISE healthy.
The BMI actually works fairly well, but most people can’t reach that goal so they think it’s wrong. I used to think that too, till I stopped making excuses and started busting my butt in the gym.
It works fine now and it shows
It should also be noted that BMI does not do a good job of classifying short or tall people, and age is a factor - the classification ranges for children (and to a lesser extent teens) are somewhat different to the ranges defined for adults.
So the OP comments on their BMI when they “graduated school.” I have no idea what age that is (not familiar with the US education system), but it’s possible that they have not fully achieved their adult body at that point, and so a BMI of 15-16 may still be reasonable (if somewhat slight).
We had this discussion last night, in the context of a very good Panorama documentary on the BBC (Why thin people are not fat - really worth watching). My daughter has in the past commented on her brother, who is 16, a geek, lazy and eats junk food, but is still skinny and has an obviously low body fat %. I pointed out that he is still hitting puberty, has an oversupply of testosterone, and once he gets a bit older (into his 20s) will revert to genetic programming and thicken up round the middle and chest like his dad (if he is not careful). My daughter got the same warning with all her paternal aunts (whose children she is most similar to) as object lessons.
But I have also demonstrated to them what can be done if you try. At the start of 2008 (age 41) I had a BMI of 36 - morbidly obese. I now have a BMI of 28, and am moderately fit (can run 10km under an hour). I still have 10 kg to go to hit a normal range BMI of 25 - possibly unachievable given my muscle distribution (I have big heavy thighs from biking), but I’ll give it a crack. One of the points of the Panorama show was that it seems that humans are genetically and environmentally programmed to hit a specific weight, and it is really, really hard to change that. So I may be stuck at 88kg (I’ve been static for a few months now), but I really intend to give it a go. My theory is that being a bit overweight and in good fitness is ok, but if I stop training for whatever reason (injury or something) I’ll just end up overweight. So I need to be as light as I can get, then if I have to cut back on training I’ll still be fine weightwise.
And I have no idea of my body fat %. My digital scales still tell me I am 30% fat, but that has not changed over the last year as I have lost weight - so I am sceptical.
Si
ANY guide that references height and weight is a screening guide. It is possible to be outside of “normal” and still be healthy but you really can’t know that without some more information. The BMI is a good tool to evaluate when all you have is height/weight but there are better evaluation methods, most of which have a cost that is hard to justify unless there is a some indicator like an out-of-normal-BMI.
There are outliers on the BMI scale that don’t fit properly in the ranges, but a lot more people think they are outliers than they really are.
Also, I have no doubt that a “skinny” teenage girl is in the underweight category, despite their feeling that they are normal.