Why the Scale Isn’t Your Best Measure Of Change
Let’s talk about that darn slab of glass or metal on your bathroom floor. I get it. The scale is easy, simple and embedded in our routine and our culture as the go-to measure of health and progress. But here’s what it doesn’t tell you: it doesn’t know the difference between fat, muscle, water, or the healing inflammation from a tough workout. It doesn’t know if you slept poorly, had Chinese food last night, or where you are in your cycle (ladies). The number it gives you? It’s vague and it fluctuates and it’s just one very tiny clue in a much larger, far more fascinating story.
Let’s look under the hood. Your body weight can fluctuate several pounds in a day based on hydration status, sodium intake, and hormone levels. For instance, estrogen and progesterone shifts in the second half of the menstrual cycle often lead to water retention—something many women recognize as bloating or puffiness. A salty dinner or even high-carb meal can cause you to retain more water temporarily, tipping the scale upward through no fault of your own. And if you've just started a new exercise routine? Your muscles retain water during the repair and recovery process, which is part of getting stronger.
There’s also the matter of digestion. If your gut is slow to move things along - which can be affected by stress, travel, hormones, or low fiber intake (about 90% of us don’t get enough fiber) the scale may reflect that too. Bowel contents have weight, plain and simple. And don’t forget: gaining lean muscle while losing fat - a process called body recomposition - often results in little to no change on the scale, even though your health is improving dramatically.
Even sleep and stress can tip the scales. One night of poor sleep can raise cortisol levels, a hormone that promotes fluid retention and can increase hunger and insulin resistance. If you're inflamed from stress, injury, or illness, your body may hold on to more water as part of the healing process. That’s just physiology. Our bodies are fluid, dynamic systems. And the scale? It only captures one row of data on one day in the book of your life.
So if the number goes up…pause. Ask questions. Am I feeling stronger? Sleeping better? Are my clothes fitting differently? Am I more consistent with my habits, and is food feeling more peaceful? These are better indicators of progress. The scale doesn’t measure your strength, your joy, your effort, or your growth. If it motivates you, great. If it messes with your mind, feel free to step away.
Carmichael MA, Thomson RL, Moran LJ, Wycherley TP. The Impact of Menstrual Cycle Phase on Athletes' Performance: A Narrative Review. Int J Environ Res Public Health. 2021 Feb 9;18(4):1667. doi: 10.3390/ijerph18041667.
