How Does Body Fat Percentage Effect TDEE?

alexreyn13
alexreyn13 Posts: 52 Member
edited February 2022 in Health and Weight Loss
So i'm 172cm tall, weight 70kg (male, 26) and I have what can be called a "skinny fat" body. I used the US navy body fat method (including an online calculator) to determine that my body fat percentage is around 27%-28%.

Normally on TDEE calculators without a body fat % it will put me at around 1980 calories, but with the percentage it lowers to 1750 (all sedentary) so which number should I go off? my goal from here is to lose the extra body fat, slimming down with minimal (or maintaining) the lean mass i currently have or hopefully even gaining some muscle/strength along the way with some at-home exercise

Replies

  • nooshi713
    nooshi713 Posts: 4,877 Member
    Taking into account body fat percentage is a more accurate method.
  • Lietchi
    Lietchi Posts: 6,846 Member
    edited February 2022
    Muscle is more metabolically active than fat (=burns more calories). So in theory, the calculator that takes into account your fat percentage should be more accurate.

    That being said, these are just calculators based on population averages, so no matter what number your pick, you will still need to 'test drive' it to see if you are statistically average or not.

    You can monitor your calorie intake during 8 weeks and monitor your weight trend for 8 weeks. Add up your calorie intake for those 8 weeks. One lb of bodyfat is around 3500 calories, so add 3500 calories for every lb lost or subtract 3500 calories for every lb gained. Divide this total by 56 and that's your average TDEE for those 8 weeks.
  • sijomial
    sijomial Posts: 19,809 Member
    But you are basing your BF% estimate on a method that is enormously variable between people, OK for some and badly inaccurate for others (it was comically wrong for me!).

    Suggest you pick a number and trial it for a number of weeks and then adjust if required. That adjustment will also take into account your logging inaccuracy. Think of the original estimate as a number to get you started. With your height, weight, age and goals I would pick the higher estimate as you really want to avoid too rapid weight loss.

    Apart from lean tissue being more metabolically active (in the case of muscle - not a lot higher burn rate at rest than fat surprisingly) a leaner, more muscular person will typically be able to achieve higher burn rates than a same weight fatter person when exercising. How much you use your muscle is a bigger variable than how much you have you could say.

    PS - apart from your purposeful exercise, investing time and effort in not being sedentary also pays dividends for health and body composition.

  • cwolfman13
    cwolfman13 Posts: 41,865 Member
    Using your BF% is going to impact your TDEE because it lowers your BMR estimate
  • anew45
    anew45 Posts: 17 Member
    Even more important than 100 -200 calories is that you start resistance training/lifting. The only way to change skinny fat is to loose fat while keeping muscle. Without lifting your body has no reason to hold muscle and you will loose both fat and muscle as you diet and defeat your goal. Your body composition will not change and you will just be a lower weight. Most people don’t know the main reason people are skinny fat in the first place is because of dieting. You can loose fat and muscle together very fast but you can put on fat way quicker and easier than muscle so the end result of the process is to be the same weight at the end of the yo-yo but more body fat and less muscle. As a new lifter you may get plenty of results at a smaller deficit/more calories because you may be able to add a small amount of muscle as you slowly loose weight and really look different in the mirror without a huge scale move.
  • squarewheels66
    squarewheels66 Posts: 25 Member
    Your BMI is in the healthy range. You have highish BF% for your gender and age. I'd focus on eating and sleeping well and doing some lifting if you want to drop BF%.

    Healthy habits are going to pay more dividends than calorie counting
  • westrich20940
    westrich20940 Posts: 921 Member
    Theoretically (if you have an accurate estimate of your BF%) it is more accurate to use that to calculate your TDEE.

    But how do you have your BF% estimate? It could be really wrong.....

    I'd suggest picking one of those numbers and manually setting your calorie goal to that --- do that for a month and then see what it does to your weight and make adjustments as necessary.