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Why the Scale Lies

Losing weight and eating healthy is tough work and nothing can be more discouraging than getting on the scale and seeing a disappointing number flash across that screen.

Don’t let the number intimidate you!

Just remember, from water retention to glycogen storage and to changes in lean body mass, daily weight fluctuations are normal and are not indicators of your successes or failures. When you’re watching your weight, daily weighing is unnecessary: but many of us can’t resist sneaking a peek at that number every morning. If you are using the scale to track your weight loss, try to weigh yourself only once a week and at the same time (usually, first thing in the morning). However, if you can’t resist the urge to get on that scale here are some things to familiarize yourself with that can influence your daily weight readings. Hopefully, once you understand how these factors influence your weight, you can free yourself from the daily battle with the bathroom scale!

Water and Sodium

Water makes up about 60% of our total body mass and normal fluctuations in the body’s water content can send scale-watchers into a frenzied state if they don’t understand what’s happening.

Water consumption and salt intake are two factors that significantly influence our bodies’ retention of water. For example, if we are dehydrated (even slightly), our bodies will hang onto its water supplies; so although it may sound strange, the less water we drink the more of it we retain! The solution? Drink plenty of water! Actually, drinking water is one of the top secrets to weight loss! How much water? A lot! We suggest up to 3L daily but, if that number seems unattainable, you can aim for half of your body weight (lbs) in ounces. Meaning, if you are a 150 lbs woman, you would aim to drink 75 oz of water daily. Start slowly and increase daily. Set a reminder on your phone or an alarm that will sound every hour to prompt you to have a drink.

Likewise, excess sodium (i.e. salt) can also play a big role in water retention, obesity and hunger. In fact, for years scientists believed that excess salt would make a person thirstier. However, recent studies have displayed a much more complex analysis. It seems that an increase in salt in the diet does not actually make you thirstier but hungrier. We’ve also known for years that an increase in sodium also increases the risk of high blood pressure and eventual cardiovascular complications.

A single teaspoon of salt contains over 2000 mg of sodium. Did you know that we should only eat between 1000 and 3000 mg of sodium a day? Sodium overload is a pitfall for many of us! Not only can sodium be found in salty nuts and crackers but also in other, less obvious snack foods. Essentially, a food doesn’t have to taste salty to be loaded with sodium! A half of a cup of instant pudding, for example, contains four times as much sodium as an OUNCE of salted nuts! Highly processed foods are more likely to have high sodium content than unprocessed foods. So, when in doubt snack on fruits, vegetables, and whole grains and always remember to read the labels on canned foods, boxed mixes, and frozen dinners!


Glycogen levels are another factor that can influence the scale. What are glycogens? Well, simply put, glycogens are stored carbohydrates. Some glycogen is stored in the liver and some is stored in our muscles. Glycogen is like an energy reserve within our bodies. However, this reserve weighs more than a pound and is accompanied with 3-4 pounds of water. When limiting your carbohydrate intake to less than 100g daily, your glycogen stores will start to deplete; affecting your weight. Although it is normal to experience glycogen and water weight shifts (up to 2 pounds per day with no change in your calorie intake or activity level), this can also explain why a “cheat meal” can make you feel like you’ve gained 3 lbs if you’ve been on a low-carb diet. The fluctuation has little to nothing to do with actual fat gains and is mostly water weight. However, the up and down of glycogen stores can make for some dramatic weigh-ins if you’re weighing yourself on a daily basis.

How much does that food weigh?

Another factor people often forget to consider when weighing themselves is the actual weight of the food they eat. For this reason, it is best to weigh yourself first thing in the morning before you’ve had anything to eat or drink. Eating a big meal before you weigh yourself is like stuffing a bunch of rocks into your pockets before stepping on the scale. Just remember, the five pounds that you gain right after a huge dinner is NOT fat. It’s the weight of everything you’ve had to eat and drink! This added weight will be gone several hours later when you’ve finished digesting it. In order to store one pound of fat you need to eat 3,500 calories more than your body is able to burn. In other words, to actually store the above dinner as 5 pounds of fat, it would have had to contain 17,500 calories! So, if the scale goes up 3 to 4 pounds overnight, rest easy: it’s likely to be water, glycogen and the weight of your last meal.

Have you pooped?

Yes, we just said it. This is important to note, too. Hopefully, you aren’t feeling constipated and you have regular, healthy bowel movements. Did you know that a bowel movement can weigh up to 1lb. Doesn’t seem like much, maybe, but if you’re constipated for several days, this can add up. Try to weigh yourself at the same time, before a meal and after your morning poop.

What Does the Scale Measure?

The 3,500 calorie rule also works in reverse. In order to lose 1 pound of fat you need to burn 3,500 calories more than you take in and that’s why it’s only possible to lose 1-2 pounds of fat per week. Of course, this is a simplistic approach and doesn’t account for your personal health history and current health status. However, if you consider following a very low calorie diet that causes your weight to drop 10 pounds in 7 days, it’s almost physically impossible for all of that to be fat! What you are really losing is water, glycogen and muscle!

This brings us to the scale’s sneakiest attribute: it doesn’t just weigh fat. It weighs muscle, bone, water, and internal organs. When you lose ‘weight’ it doesn’t necessarily mean you’ve lost fat. In fact, the general bathroom scale has no way of telling you what you’ve lost (or gained). Losing muscle, for example, is nothing to celebrate. Muscle is a metabolically active tissue. The more muscle you have, the more calories your body burns, even when you’re resting! This is one reason why a fit, active person is able to eat considerably more calories than the dieter who is losing muscle tissue by limiting calories on a crash diet.

Remember: the scale can’t tell you how much of your total body weight is lean tissue and how much is fat.

There are other ways of measuring your body composition that can give you a more thorough analysis of your percentages of fat, lean muscle and water.  They do vary in convenience, accuracy and cost, but many can give you a great starting point for future gains or losses.

What are some ways to measure body fat? Skin-fold callipers pinch and measure fat folds at various locations on the body. These measurements can often be performed at a local fitness centre or with a personal trainer. Hydrostatic (or underwater) weighing involves a person, in minimal clothing, exhaling all of the air from your lungs before being lowered into a tank of water to measure their body density. Although this can give a relatively accurate reading of body fat, it’s also important to note that body density may vary depending on the weight of bones and muscle. Also, accessing this kind of testing is a bit more challenging as the equipment is quite expensive and hard to find in health clinics. Another example is a scale that uses bioelectrical impedance. This measures the degree to which your body fat impedes a mild electrical current. Just think, fat is less conductive than water. If you have a high fat percentage, the electrical current will move more slowly throughout your body. On the flip side, if you are dehydrated, you may not get an accurate reading of body fat percentage.  

But, don’t worry! The best way to measure your body composition is to use your own eyes! Ask yourself: How do I look? How do I feel? How do my clothes fit? The answers to these questions are the true measurements of success! If you are exercising and eating right, don’t be discouraged by a small gain on the scale.

Weight fluctuations are normal. Expect them and take them in stride!

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