The bathroom scale is by far the most popular and effective tool to measure body weight, but how regularly we weigh ourselves when dieting tends to be based on habit or convenience. Both daily and weekly weigh-ins can support weight loss goals, but studies have repeatedly found one more successful than the other. Does it even matter?

promptly make adjustments and easily trace causes

To weigh or not to weigh

Documentaries and TV shows like The Biggest Loser have led us to believe in the weekly weigh-in, but many studies link it to little or no weight loss in the short and long-terms, the same outcome for those not weighing at all. Some experts even suggest avoiding the scales completely, especially adolescents and adults at risk of developing eating disorders. For the majority though, weighing-in somewhat regularly is more effective than not weighing-in at all and at least two dozen studies have found only minor differences between daily and weekly weigh-ins.

Self-monitoring is key

Although weighing-in daily is the clear winner across a number of other studies, the secret to weight loss success is self-monitoring, which includes getting on the scales. The more often you practice self-monitoring, the more you lose as it enforces and instils healthy behaviors over the day, like a reminder that you’re on a diet. You weigh yourself in the morning and that action sets the tone for the rest of the day. You’re more likely to stick to your diet and exercise regime to avoid repeated daily failure, but it’s also habit-forming.

Daily weigh-ins promote self-evaluation and self-correction, but even weighing most days of the week can result in better choices and weight loss. As you observe fluctuations and patterns, you can promptly make adjustments and easily trace causes, and you're less likely to gain back the weight. One study also found a positive link between regular weigh-ins and achieving step goals.

If daily weigh-ins are incompatible with your lifestyle or schedule, at least set daily exercise goals and spend a few minutes each day logging meals and activity. This daily practice could improve behavior awareness throughout the day and help you avoid unexpected gains when you eventually weigh-in.