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Weight Loss Determinations

Wanting to lose weight is a feeling that most of us face at some point in life. There are too many commercials and ads spouting “Lose 40 Pounds in 4 Days!” that make it sound quick and easy to drop that extra fat. But knowing how lose weight safely, and how much you should actually aim to lose, can help you make an achievable weight loss goal , and follow through to succeed.

Keeping Track

As you’re on your fat loss journey, it’s important to track your progress along the way. By following along closely and recording any losses or gains in your weight and body composition, you can accurately tell if what you’re doing is working or not. Many people see changes simply by tracking their meals and diet, since recording what you eat makes you more conscious of what you’re putting into your body. Having these records, in collaboration with a written account of your exercise routine, you can more easily spot trends to see what works and leads to bigger changes, and what sets you off and sabotages your plan.

How much to lose?

Before jumping into high gear to lose weight, you should first find out how much weight you actually should and would want to lose. To make this easier, fitness level categories were created based on body composition, and Body Mass Index (BMI). Figuring out where you stand in each of these categories can help you figure out your health level, and help guide you in determining how much fat to lose.

Body Composition

Body composition is the breakdown body weight into lean body mass and fat. This is usually expressed in % of body fat. Finding out your current body composition can be a little difficult and requires special tools, but is extremely accurate and helpful in determining how much fat to lose. When you know your body fat percentage, you can then figure out your lean weight and your body fat weight. These numbers are helpful if you cannot consistently measure your body composition, and can only use a scale later.

Body Fat Percentage Categories:

CATEGORY      WOMEN %      MEN %

Essential Fat      10-13%          2-5%

Athletes             14-20%          6-13%

Fitness               21-24%         14-17%

Average             25-31%          18-24%

Obese                >32%             >25%


Once you know what category you fit into, you can make an educated decision on your ideal category and body fat percentage. To figure out how much you want to lose, you can use the following calculation:

Goal Body Weight = [Lean Body Weight / (100% - Goal % Fat)] x 100

If you currently weigh 160 pounds, and are at 20% body fat, you can easily determine that you have 32 pounds of fat, and 128 pounds of lean body weight. This in the Average Category, which is just fine. If you want to drop down to 16% body fat, and reach the Fitness Category, you can calculate your goal body weight and how much you would have to lose, by doing the following calculations:

Goal Body Weight = [Lean Body Weight / (100% - Goal % Fat)] x 100

Goal Body Weight = [128 / (100% - 16%)] x 100

Goal Body Weight = (128 / 84) x 100

Goal Body Weight = 1.524 x 100

Goal Body Weight = 152.4


With these numbers, your goal body weight would be 152.4 pounds, so you would aim to lose 7.6 pounds of body fat to reach that goal.


If you cannot find your body fat percentage, you can also use your Body Mass Index, or BMI. While it’s not the most accurate way to measure the body because it is solely based on total weight and height, it can be helpful as a quick general guideline.

BMI Categories:


Normal weight: 18.5-24.9

Overweight:  25-29.9

Grade 1 Obesity:30-34.9

Grade 2 Obesity:35-39.9

Grade 3 Obesity:>40


You can find your BMI with the following calculation:

BMI = Weight (lbs) x 703 / Height (in) / Height (in)

For example, here is the calculation for a person who weighs 160 pounds and is 5’10’’:

BMI = Weight (lbs) x 703 / Height (in) / Height (in)

BMI = 160lbs x 703 / (5’10’’) / (5’10’’)

BMI = 160lbs x 703 / (5x12 + 10)in / (5x12 + 10)in

BMI = 160lbs x 703 / 70in / 70in

BMI = 112,480 / 4900

BMI = 22.955

This person would have a BMI of 22.955, and would therefore be in the middle of the Normal Weight Category. While they do not necessarily need to lose any weight, they do have some wiggle room if they would like to.

Safe Rate

According to great sources like the CDC and more, a safe rate of fat and weight loss is somewhere around 1 to 2 pounds per week. This is based on average metabolic rates and following healthy weight loss techniques. Losing more weight faster than this can lead to health problems, or be a sign of other issues.

So if based on the calculations above, you decide to lose 10 pounds of fat, you should expect this process to take you 5 to 10 weeks. If this sounds like too long and your friend Karen swore to you that her best friend Michael’s cousin Pat lost 14 pounds in 7 days, take a minute to think about it and take that story with a grain of salt. While Pat could have done that, but that doesn’t mean they did it safely, or that it would necessarily work for you.

Making sure that you’re losing fat safely is very important to your overall health. Sticking to incremental changes to your eating and exercise routines in order to burn fat will help to make sure that you’re building lasting healthy habits rather than crashing and regaining that weight again right after you lose it.

Using these calculations to see where you stand based on your body composition and weight can help you better determine just how much excess fat you should aim to lose. These are an excellent starting point on your journey to live a healthier and happier life.