Does Body Fat percentage effect your metabolism?

13

Replies

  • lithezebra
    lithezebra Posts: 3,670 Member
    generally speaking, your body does NOT like being lean.

    My body seems to be fine with it, if you consider 17-18% BF to be lean for a female body. It's too lean for some of the BF calculators that take my age into account, but it's easy to maintain. I think that it takes a lot of people a while to get used to eating less.

    It takes work to stay that way, which is what he's getting at. Your body tries to store calories as fat whenever it gets the chance. Keeping lean means not giving it the opportunity by maintaining calorie intake and exercising.

    The only reason it takes work to stay that way is that we live in a society in which food is plentiful for most people. If we lived even 100 years ago, most of us would be working hard to get enough food to live.

    True, which is why, physiologically speaking, the body is quick to accumulate fat reserves when given the chance.

    The body can lose them even more quickly, if you get sick or get lost in the woods.
  • peterjasper
    peterjasper Posts: 41 Member
    calculate-my-body-fat-percentage.gif
    the chart is from the world health organization, which bases it these categories on a variety of HEALTH. factors

    Trainers use a different chart, which does not account for age.
    Think about it, it's how they sell there services.
    1) They want to acheive more extreme results so they can show you their track record of "success" and
    2) The more extreme your goals are the easier it is to sell you on their services.

    Really interesting point there. I was wondering what body fat % I should aim for.
  • rsalty
    rsalty Posts: 68 Member
    Just curious, does your resting metabolism increase if you have a lower body fat percentage and by how much?

    Many answers, and the set that are in fact correct do contradict each other. The answer depends on if weight changes at the same time. See rest of thread.
    Also how can I determine body fat percentage by appearance?

    http://www.builtlean.com/2012/09/24/body-fat-percentage-men-women/

    I had the inverse of this question: I picked an appearance range and wanted to know what body fat range I should aim for. The article at the link above was a great help. I found that article by doing an image web search for "body fat percentage".
  • HWeatherholt
    HWeatherholt Posts: 283 Member
    Just curious, does your resting metabolism increase if you have a lower body fat percentage and by how much?
    Also how can I determine body fat percentage by appearance?

    If you google it, you can find directions on how/where to measure and then the math formula to determine your body fat %. Or you can get a scale that also measures body fat fairly inexpensively, same for the hand held analyzer, they are not perfect though. But it will give you an idea. If you want to know your exact % you can have a professional measurement - most accurate are the water or air displacement tears.
  • littleknownblogger
    littleknownblogger Posts: 67 Member
    The less you weigh, the lower your BMR will be. The leaner you are, the higher your BMR will be as a function of your bodyweight.
  • wild_wild_life
    wild_wild_life Posts: 1,334 Member
    generally speaking, your body does NOT like being lean.

    My body seems to be fine with it, if you consider 17-18% BF to be lean for a female body. It's too lean for some of the BF calculators that take my age into account, but it's easy to maintain. I think that it takes a lot of people a while to get used to eating less.

    It takes work to stay that way, which is what he's getting at. Your body tries to store calories as fat whenever it gets the chance. Keeping lean means not giving it the opportunity by maintaining calorie intake and exercising.

    The only reason it takes work to stay that way is that we live in a society in which food is plentiful for most people. If we lived even 100 years ago, most of us would be working hard to get enough food to live.

    True, which is why, physiologically speaking, the body is quick to accumulate fat reserves when given the chance.

    The body can lose them even more quickly, if you get sick or get lost in the woods.

    Again true, but most of us here are dealing with the perils of overabundance rather than the risk of getting lost in the woods, a fact which, IMO, we should all be grateful for. There are certainly a large number of people in the world who have no trouble staying "lean" and would give a lot to have that problem.
  • Azdak
    Azdak Posts: 8,281 Member
    Unless anyone has evidence to the contrary, I don't think it's necessary to assume that the healthy body fat% should rise as men and women age. I think it probably does statistically, but then so does weight and we all know that adding weight as the years go on is NOT inevitable.

    So true, what they consider healthy does though. And I'm sure with all the other stresses on the body, having less fat as you get older would probably be better.

    Same claim made that metabolism goes down as you age. Well sure, if you lose muscle mass due to less use of muscles, as the average population has happen.
    But that doesn't mean it has to happen.
    Now, I have seen the "studies" (really case studies on individuals), that at a certain point (which would vary of course), the metabolism takes a nose dive even for those that are active, about the time their body stops being able to recover as well, they get sick more, heal slower, ect.
    So not that their system all of a sudden after 80 years figured out how to become more efficient doing everything it needed to, but rather it stopped doing as much as often.

    Same claim made regarding HRmax, lowers as you age, as the formula's show. Well, no, doesn't need to if you maintain a cardio fitness program and keep it up. My tested has not lowered in many years. Shoot, I'm 26 by standard formula. Huh, how come I don't feel 26.....

    Most (all?) studies done on effects of aging and fitness have been cross-sectional, not longitudinal. So they reflect the way the population IS at a given point in time, not the effect of the variable over time.

    As you can imagine, doing longitudinal studies on the effects of exercise is not easy to do, so those doing the HR tables, BF tables, etc are not being intentionally deceptive. And considering the relatively small number of people who engage in regular, vigorous exercise, the tables are still likely accurate for a big chunk of the population.

    A well-know ex phys researcher did follow a cohort of masters swimmers for 30 years. He reported than while performance times changed, as long as intensity and volume of exercise remained constant, VO2 max did NOT change between the ages of 25 and 55.
  • EvgeniZyntx
    EvgeniZyntx Posts: 24,208 Member
    Yes, BF% affects your metabolism. Assuming a pound of LBM burns around 7-10 cals/day (and fat somewhere around 2 cals/day/lb). Take two 150 lb person with 10% difference in body fat.

    The leaner person with 10% less BF at the same weight will burn about 35000 to 50000 more calories per year. So on the same diet, if the leaner individual was at maintenance the person with the higher bf% will theoretically gain about 10-15 lbs.

    Keep your LBM up!
  • BinaryPulsar
    BinaryPulsar Posts: 8,927 Member
    Maybe this is wrong, but it was actually my understanding that older women that weight train can maintain a lower bf% and be healthier than a younger women (at the lower bodyfat). Younger women, in the childbearing years need slightly more body fat (and they carry it well for a number of factors, including the youthfulness of their skin and naturally higher lbm, among other factors), but that as we age, we will naturally reduce our body fat (if we are fit, active, strength training). The people that say body fat increases are saying that because lbm decreases, but that is a result of inactivity, not strength training, not eating enough protein. Sure metabolism decreases with age, but our bodyfat needs do not increase (maybe I'm wrong about that).
  • Azdak
    Azdak Posts: 8,281 Member
    Yes, BF% affects your metabolism. Assuming a pound of LBM burns around 7-10 cals/day (and fat somewhere around 2 cals/day/lb). Take two 150 lb person with 10% difference in body fat.

    The leaner person with 10% less BF at the same weight will burn about 35000 to 50000 more calories per year. So on the same diet, if the leaner individual was at maintenance the person with the higher bf% will theoretically gain about 10-15 lbs.

    Keep your LBM up!

    Theoretically, but not often in reality. That's because there are so many other factors involved. It's why these discussions always wind up in a dead end--it's almost impossible to isolate one factor and say --"yeah, that's it".
  • lithezebra
    lithezebra Posts: 3,670 Member
    Maybe this is wrong, but it was actually my understanding that older women that weight train can maintain a lower bf% and be healthier than a younger women (at the lower bodyfat). Younger women, in the childbearing years need slightly more body fat (and they carry it well for a number of factors, including the youthfulness of their skin and naturally higher lbm, among other factors), but that as we age, we will naturally reduce our body fat (if we are fit, active, strength training). The people that say body fat increases are saying that because lbm decreases, but that is a result of inactivity, not strength training, not eating enough protein. Sure metabolism decreases with age, but our bodyfat needs do not increase (maybe I'm wrong about that).

    I'd like that to be true. One thing that does seem to be uncontested is that everyone would be well advised to continue strength training throughout life, especially in middle and old age.
  • BinaryPulsar
    BinaryPulsar Posts: 8,927 Member
    Maybe this is wrong, but it was actually my understanding that older women that weight train can maintain a lower bf% and be healthier than a younger women (at the lower bodyfat). Younger women, in the childbearing years need slightly more body fat (and they carry it well for a number of factors, including the youthfulness of their skin and naturally higher lbm, among other factors), but that as we age, we will naturally reduce our body fat (if we are fit, active, strength training). The people that say body fat increases are saying that because lbm decreases, but that is a result of inactivity, not strength training, not eating enough protein. Sure metabolism decreases with age, but our bodyfat needs do not increase (maybe I'm wrong about that).

    I'd like that to be true. One thing that does seem to be uncontested is that everyone would be well advised to continue strength training throughout life, especially in middle and old age.

    Yeah, definitely!!
  • GrannyGwen1
    GrannyGwen1 Posts: 213 Member
    :flowerforyou:
  • The leaner you are, the less calories your body needs to maintain itself.

    I believe you mean more.

    no. he means less.
  • EvgeniZyntx
    EvgeniZyntx Posts: 24,208 Member
    Unless anyone has evidence to the contrary, I don't think it's necessary to assume that the healthy body fat% should rise as men and women age. I think it probably does statistically, but then so does weight and we all know that adding weight as the years go on is NOT inevitable.

    Liver protein synthesis does decrease with age as does enzymatic activity (which are related). Therefore protein turnover will shift. Can this be offset? Most likely, somewhat. But let's face it, 90 year olds will not have the optimal potential LBM of their 20 year old self.

    Now on the individual level it doesn't mean you can be in better shape at 80 then you were at 21. But your potential at 21 was definitely higher.

    So really it depends on your starting point and effort. It is possible to be a Charles Eugster (90ish body builder and TEDx speaker) but the effort (I'm not even sure he's "natural") will be higher.
  • SideSteel
    SideSteel Posts: 11,068 Member
    So really it depends on your starting point and effort. It is possible to be a Charles Eugster (90ish body builder and TEDx speaker) but the effort (I'm not even sure he's "natural") will be higher.

    "Charles you're looking pretty jacked. And dry! You juicin bro?"


    "Yes. Prune juice"
  • sijomial
    sijomial Posts: 19,811 Member
    2. It would take a considerable amount of muscle mass to make a noticeable difference in metabolism. If you have someone who is 235lbs and 10% fat vs someone who is 235 lbs and 25% fat, there is probably a difference--but that's because you are looking at roughly a 30lb difference in muscle mass. The majority of people will not fall into that category.

    The difference for me was about 150 kcalories more I could eat per day once I figured my BMR using my fat % vs other more generic formulas. I think that is quite a lot actually.

    Agree 150/day is significant as it adds up over time. It does though put it in perspective how much muscle mass you have to build to make a difference and also counters some of the anti-cardio bias often seen on the forums. That 150/day could easily be one decent cycle a week, a couple of average intensity cardio sessions or half an hour of walking every day to achieve the same calorie balance. There's many ways to skin a cat!!

    I'm not anti weight training or rabidly pro cardio by the way as I do, and enjoy, both.
  • BrendaVJP
    BrendaVJP Posts: 3 Member
    Does anyone have any advice on how to lose the belly fat?
  • sunman00
    sunman00 Posts: 872 Member
    this ^

    men are supposed to have a higher sedentary TDEE than women, but mine is just above an average womans and my wife is just below an average mans
    it's individual, & it's genetic
  • sunman00
    sunman00 Posts: 872 Member
    generally speaking, your body does NOT like being lean.
    Simple but perfectly put! :)

    I think everyone is different, and probably mostly has to do with genetics. I have always been fairly lean and so has my father. It is just our body type.

    this ^

    men are supposed to have a higher sedentary TDEE than women, but mine is just above an average womans and my wife is just below an average mans
    it's individual, & it's genetic

    -reposted as missed the quote 1st time :(