Ask LH: How Do I Accurately Track My Weight And Fat Loss?

Ask LH: How Do I Accurately Track My Weight And Fat Loss?

Dear Lifehacker, When I weigh myself on a scale multiple times a day, sometimes I weigh a lot more in the morning than I do at night. I’ve also heard it’s more important to measure fat loss than weight loss, but how do I track that accurately? I want to measure my progress, but I don’t know how. Please help! Thanks, Losing Track

Photo by Mirana (Shutterstock), Merydolla (Shutterstock), Michael Jung (Shutterstock), DVARG (Shutterstock), and Lightspring (Shutterstock).

Dear LT,

Tracking your weight and fat loss poses a challenge, but you can do it without a ridiculous amount of effort. As you mentioned, tracking body weight doesn’t necessarily indicate progress in one way or another due to a couple of factors.

First, you body weight fluctuates greatly throughout the day, depending on your body type, food and water intake, and activity levels. Additionally, additional weight might indicate positive progress because you’ve gained as in muscle mass. If you do need to reduce your weight to a healthier level, daily monitoring will prove useful. You just have to account for fluctuations, and we’ll discuss how to do that in a bit.

For many people, tracking fat loss proves more effective when attempting to measure progress because fat is, specifically, what they want to lose. Some scales measure body fat and muscle mass, but they can be problematic as well. First, they attempt to provide an overall assessment of total body fat rather than measurements based on specific key areas of your body. More importantly, they have a very high margin of error (above 5 per cent) so you end up with unspecific and quite probably incorrect information. Correctly measuring body fat, in most cases, requires the aid of a professional. Some come at a reasonable cost and others will break the bank. Later on, we’ll discuss these methods.

You may find that tracking your fat loss accurately doesn’t matter that much because other less-specific methods of gauging progress take less time, money and effort. You want to see positive change in general, not necessarily as a series of numbers, so constant measurement may not suit you.


Track Your Body Weight Accurately


Scales may provide different body weight readings at different times of the day, but that doesn’t point to inaccuracy. Rather, your body weight fluctuates throughout the day. Water, food, clothing and other factors contribute to how much you weigh at any given time. You’d lose your mind if you attempted to account for these constant changes in your weight, so you want to concentrate on averages. That means doing the following:

  1. Get yourself a decent digital scale.
  2. Weigh yourself at least twice a day: when you wake up, before you go to bed, and in the middle of the day (if possible). Ideally, weigh yourself naked. Clothing can add weight, so you should avoid it if possible. Chances are you can’t weigh yourself in the nude in the middle of the day, however, so weigh yourself before and after you get dressed a few times to find out how much (approximately) your weight changes when dressed so you can subtract that amount if you need to weigh yourself clothed.
  3. Average every weight measurement for the day.
  4. Take those averages and average them each week.

Average measurements will keep you aware of how your body weight changes throughout the day. When attempting to lose weight, you may feel discouraged if you see your weight rise after working really hard at your fitness goals for a week or so. Seeing the fluctuations in your weight each day, and likely a decline over time (if you need to achieve a healthier weight), keeps you motivated. You won’t find a one kilogram gain upsetting in the morning if it disappears when you weigh yourself again at night. Daily and weekly averages will provide you with a more accurate idea of your actual weight, too, so you can see actual progress over the long term (in the event healthy weight loss is a relevant goal).


Track Your Fat Loss Accurately


Accurately tracking fat loss requires regularly body fat measurements with a reasonably low margin of error. While you have many options available to you — dual energy absorptiometry , ultrasound, water displacement, and a number of others — you can spend a lot of money unnecessarily. Tracking your fat loss doesn’t have to require expensive equipment, and if you have more appearance-oriented goals you may prefer methods that don’t track the numbers at all.

Figuring out the right method for you depends on a variety of factors, but if you’re young and have a body mass index (BMI) under 30 (calculate yours here) you should consider professional skin fold measurements with calipers. Although you can’t easily and accurately these measurements yourself, seeking out a professional will cost less than the aforementioned techniques. To learn more about this method, I spoke with certified personal trainer Mariana Abeid-McDougall. She explained that with a few additional measurements, you get an accurate idea of your current situation:

For general health gains, usually a combination of body mass index (BMI), waist circumference, and sum of 5 skin folds (So5S) is the best assessment, as it provides information on both the amount and distribution of body fat in order to gain a better assessment of body weight, adipostiy, and fat distribution.

She also warns that your weight and fat loss goals ought to focus on health first and appearance second, otherwise you can set yourself up for disaster:

It should be noted, however, that it is hard to determine “ideal weight” for those who are not high level athletes (where this actually matters) and that the assessment of ideal weight from percentage of fat is subject to many errors. In other words, we should move from concentrating on weight loss for aesthetics and move to concentrating on weight loss for health benefits where necessary. Many individuals who want to lose weight often times do not need to do so — they just want to do so to fit society’s current beauty norms. This results in both an unhealthy body image and, in severe cases, eating disorders in both men and women.



For these reasons, you want to set realistic goals. When aiming for a healthy body fat percentage, women want to stay under 25 per cent and men under 20 per cent. Women shouldn’t drop below 18 per cent and men below 12 per cent. (Note: Women naturally have higher percentages of essential fat than men which necessitates higher goals.) On top of that, when working towards a healthier body you should always remember the following:

  1. Your body differs from everyone else’s body. While we share a number of similarities as humans, what works for you may not work for someone else. Always remember this when reading information about health (including this article).
  2. What you know about your body now will change dramatically as you continue to age. A 10-year-old’s body differs greatly from a 20-year-old’s, which we find obvious because we can see it. Our change in appearance in adulthood isn’t so dramatic, so we don’t always notice how different our bodies become. What works when you’re 20 may not apply when your 30, and those changes continue throughout your life.
  3. Patience matters. Progress doesn’t happen overnight, and you may notice very little change in the beginning. When setting weight loss goals and creating your plan to achieve them, ignore the mirror and other incredibly imprecise “measurements” for a month. Micro-measurements don’t look like progress. The difference a month of positive work can provide does. Seeing that change requires patience.

You should also consider that tracking fat loss so specifically may not help you. You can measure waist circumference yourself, and fitness and nutrition coach Liz Barnett notes that you’ll find useful evidence in everyday life:

I think using your wardrobe is a great indicator. A good sturdy pair of jeans don’t lie. You may not have a number to go by, but you’ll know if your composition has changed.

If you feel bloated you shouldn’t gauge your success that way, of course, but often times the progress that matters to us most is how we look and feel every day. When gauging anything related to your health, never forget to measure how good you feel as well.

Cheers Lifehacker

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A very special thanks goes out to Ontario-based personal trainer Mariana Abeid-McDougall (BPHE, BA, BEd, CPT) and fitness and nutrition coach Liz Barnett for their contributions to this post.


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