Here’s a good reason to invest in (and actually use) a scale: According to the National Weight Control Registry, 75 percent of people who successfully lose weight (and keep it off) weigh themselves at least once per week. A 2012 study published in the Journal of Nutrition and Dietetics agrees, concluding that people who lose weight are less likely to regain it if they weigh themselves regularly. That’s because stepping on the scale provides people with a sense of accountability, and allows for a change in direction if the current weight-loss plan isn’t cutting it.
But as I learned during my time as an athlete (the only time I ever bothered to set foot on a scale), my weight can sometimes increase or decrease by as many as 10 pounds over the course of a day—and that’s not because I don’t know how to use a scale. “Weight is determined by several factors: Fluid intake, food intake, exercise (or sweat released), salt intake and so on,” explains Dana Hunnes, senior dietitian at the Ronald Reagan UCLA Medical Center. “As a result, our weight fluctuates, because we’re drinking, eating and sweating—we’re primarily gaining or losing water weight.”
Little of this results in actual weight gain, i.e., the accumulation of fat—this is extra weight from fluids and foods consumed over the course of the last day or so. “Real weight gain has a lag effect,” Hunnes emphasizes. “If you’re overeating for weeks, that will reflect on the scale as an uptrend in weight over time.” So, if the scale says you gained five pounds directly after a single night of drinking and eating yourself stupid, don’t chuck it out the window—it’s mostly just water (or beer) weight that your body will shed over the next 24 hours or so.
This being the case, though, when is the best time of day to weigh yourself?
“First thing after waking up and using the restroom,” says Hunnes, adding that it’s also important to avoid eating or drinking before stepping on the scale. “You haven’t had a chance to lose weight via sweat, or to put on water weight,” she says. As a result, you’ll see a lower number that’s a more accurate reflection of your actual weight, without the extra pounds added by breakfast. The idea here is that you should be tracking your average (but actual) weight over a long period of time—not focusing on the minor day-to-day differences.
It also helps to ensure that your scale is on a hard, flat surface—carpets are a big no-no—and that you’re standing with your weight evenly distributed across both feet.
Still, unless you’re really trying to lose a lot of weight, should you even be stepping on the scale regularly in the first place? Not necessarily, say the experts. “For the average healthy person who is trying to lose weight or put on muscle, it can be disheartening to step on a scale and not see that number budge, even if you see changes in your body shape or the way your clothes fit,” Hunnes says. “Because of that, I think using a scale depends on the person, the context and the end goal.”
“With my clients, we use more telling measurements, like body composition [muscle mass and body fat percentage] with tools like an InBody,” says Jonathan Jordan, an award-winning trainer at Equinox Fitness. “I also use the mirror test [that is, stepping in front of a mirror with minimal clothing to assess body fat], photographs, and most importantly, fit of clothes and how my client feels to track changes.”
If you still want to keep track of your weight, though, Hunnes recommends stepping on the scale once per week, on the same day and at the same time. “Any more often than that is nerve-wracking, and you may flinch at every little up and down,” she says. “Any less than that, and you may miss an upward trend.”
Or in the case of your waistband, outward.