How many calories should I eat to lose weight?

DebbieLyn63

I found some very good and accurate online calculators to help find out my correct BF% and BMR.

I was confused by the extremely wide range of results I would get from different BF% calculators I found online. My results ranged from 28% up to 80% on different sites. My problem is that I carry all of my weight right in my belly. I have little chicken wing arms and bird legs, so the calculators that use wrist and forearm measurements were way off.

I finally found one that is accurate for my body shape. I am a 49 yo female, so many of us at this age are my shape as well.
This is the one that is the most accurate for me, so if you carry your weight in the midsection like I do, you might try it.

http://lowcarbdiets.about.com/library/blbodyfatcalculator.htm

I am 5'6", currently 208 (down from 228) and this showed me around 48% body fat. (YIKES!, The truth hurts)

Knowing my body fat % allows me to use the Katch-Mcardle BMR calculator, which takes into account your BF% instead of just your height and weight. My BMR is actually over 200 calories lower than the MFP BMR calculator says, which puts my TDEE at an even lower rate. If you have a higher BF%, your BMR will be much lower than someone of the same weight who has more muscle and a lower BF%.

http://www.calculatorpro.com/calculator/katch-mcardle-bmr-calculator/

For those of you who are having trouble losing at the calorie level you are at, but are afraid to go lower, try using these calculators to figure your BF% and BMR and see if it makes a difference.

onyxgirl17

nice

With body fat calculators, the more measurements you take the more accurate they tend to be. Mine is between 27-29%.

CoderGal

The thing about bf calculators is that the standard deviation for error is enormous. Different people carry weight in different parts of their body. Going by circumference isn't accurate because of this. For a more accurate result, go with mostly anything else. Calipers are common, so are BIA. They still have a margin for error but over time you'll get an idea of what you are...if you want to be accurate, do a displacement test.

For more information about types:

...
There is a large deviation in my examples based on the same information due to the different ways to measure body fat (17%-25.2%) but some of those values are suppose to be more accurate then others. Also, remember that the percentages are a ratio (I know, it seems obvious now that I've said it). Some people don't seem to realize that if you lose weight, your fat percentage can stay the same (though you still might be on the right track). You're likely to lose muscle and fat while losing weight, so the ratio will only slide in your favor if you increase your muscle. If your body fat percentage is fluctuating this is normal. I'd prefer comparing values month to month rather then week to week. The body fluctuates a lot, especially if you're female.

Other BF Equations:
Brozek formula: BF = (4.57/density - 4.142) * 100
Siri formula is: BF = (4.95/density - 4.50) * 100
A few ways to measure BF/LBM:

Hydrostatic (Underwater) Weighing - This is the most accurate way of measuring since it doesn't predict body density. There is a error margin for residual volume (lung capacity). Remember, the density (mass/volume) of water changes with temperature (water becomes larger when it freezes into ice cubes for example).

density_body/density_water = density_body/(~1g/cm^3) = weight_body/(weight_body - weight_immersed)

Skin Fold Methods - A pair of calipers/callipers can be used to pinch standardized parts of the body such as your bicep and belly, determining the subcutaneous fat layer thickness. These sites are measured several times and averaged, and an average is taken of the averages to determine body fat percentage. The calculations some people use seem to vary and consist of body mass index rating scales so I will not list them here. The same person has to accurately measure you the same way and over months you can notice a trend of what's happening to your body fat. This can be done at most local gyms, demonstrations are available on youtube.

Weight Scales/Bioelectrical impedance analysis (BIA) - This functionality is built into many weight scales and other devices (such as Omron hand grippers) these days. The values can vary greatly, even if you have 2 of the same scale (according to my scale manual). Scales that can do this are actually reading your electrical impedance, so it requires skin to metal contacts (this is why you do not receive a % value if you are wearing socks). These scales can figure out your total body water (TBW), which can help calculate LBM, BF and bone mass. Since this depends on your TBW, the values can vary greatly depending on if it's that time of the month, you're hydrated, your hot (related to damp skin), you're losing weight etc etc. It can also be inaccurate depending on where your carrying your fat. For example, if you carry your weight in the top half of your body and use a scale that sends the current through the bottom half.

V=Voltage=IR=Current*Resistance=Current*|Impedance|^(Imaginary#*phase)=Complicated=you have as much equipment then me in your house.

Example (me): Thinner Glass Body Analysis Scale reading BF% = 17.0% fat
BF = 20.4lb
LBM = 120lb - 20.4lb = 99.6lb
Body Mass Index (BMI) - Your BF can be calculated from your BMI (sex=1 if male, 0 if female).
Child body fat % = (1.51*BMI) - (0.70 * Age) - (3.6 * sex) + 1.4
Adult body fat % = (1.20*BMI) + (0.23 * Age) - (10.8 * sex) - 5.4
Example (me): BF% = (1.20*18.8) + (0.23*29) - (10.8*0) - 5.4 = 23.83% fat

Anthropometric/Height and Circumference Methods - The U.S. Marine Corps and U.S. Army (Department of Defense) use this method along with Covert Bailey and fat2fit's body fat calculator. They make calculations based on mass, and the circumference of various body parts such as waist, hip, bicep, forearm and wrist.
U.S. Army (Department of Defense) Military BF Calculator: http://www.fat2fitradio.com/tools/mbf/
Example (me, from calculator): BF% = 19.1% fat
BF = 22.9lb fatLBM = 97.1lb
Covert Bailey BF Calculator: http://www.fat2fitradio.com/tools/cbbf/
Example (me, from calculator): BF% = 19% fat
BF = 23lb fat
LBM = 97lb
Fat 2 Fit BF Calculator: http://www.fat2fitradio.com/tools/bf/
Example (me, from calculator): BF% = 25.2% fat
BF = 30.2lb fat
LBM = 89.8lb

http://www.myfitnesspal.com/topics/show/637094-cinderella-s-weight-loss-knowledge

DebbieLyn63

nice

With body fat calculators, the more measurements you take the more accurate they tend to be. Mine is between 27-29%.

Onyxgirl- saw your profile and am sorry you lost your mom at such a young age. I am 49 now, and my mom died in June from Diabetes, so it really hits home with me. Good for you for making good changes in your health now while you are still young. You are an inspiration!