Should I weigh myself every day? What the research says
For most people, yes. Daily weighing is linked to greater weight loss13, and for most it doesn't appear to harm mood35. The trick is to weigh yourself under the same conditions every morning and look at the weekly average, not any single day.
What the research shows
In an American trial, 91 adults with overweight were given either a smart scale, a graph of their weight and weekly emails with feedback, or nothing at all, for six months. The daily weighing group lost an average of 6.6% of their body weight, against 0.4% in the control group2.
The researchers then looked more closely at those who had the scales. Half weighed themselves every single day. The other half weighed in on 5.4 days a week on average. Even so, the everyday weighers lost 6.1 kg more1.
The daily weighers also picked up more of the habits that help with weight control1. So the scales don't work on their own. They remind you of what you're aiming for, and you act a little differently for the rest of the day.
Scales work best alongside everything else
A review of 17 studies found that regular weighing went with greater weight loss3. But a separate pooled analysis showed it's unclear whether weighing on its own works. Added to a wider programme of diet and habits, though, it gave an extra 1.7 kg of weight loss4.
The same analysis found no clear difference between weighing daily and weekly4. So the scales aren't magic. They're a tool, and they help most when you're also keeping an eye on your food.
Won't it make me feel worse?
It's a fair worry. The review of 17 studies found no link between regular weighing and depression or anxiety3. A pooled analysis of 29 tests also found no link with mood, body image or disordered eating, though there was a small negative link with self-esteem and psychological wellbeing5.
The picture isn't the same for everyone. Another review found more negative links among women and younger people, while people with overweight who were in treatment more often showed no link or a positive one6. If you've had an eating disorder, or the scales make you anxious, weigh yourself less often and talk to your GP.
How to weigh yourself
- In the morning, after the loo and before you eat or drink.
- In the same clothes, or none, each time.
- On the same scales, on a hard, level floor.
- Note the number down, or take a photo of it, straight away.
How to read the number
Your weight moves from day to day for perfectly ordinary reasons. Many people are heaviest on Sunday and Monday, with weight usually falling again from Tuesday7. That's normal and not a sign that things are going the wrong way7.
- Look at the average over a week, not a single morning.
- Compare week with week, or with the same point in your cycle.
- Ask what the number is useful for today, not what it says about you.
- Gone up? It's probably water. Check again in a couple of days.
Read more about why your weight fluctuates, and how a photo food diary fits alongside the scales.
Questions
Is weighing once a week better?
One pooled analysis found no clear difference between daily and weekly weighing4, while in another trial the people who weighed every day lost more1. Daily weighing gives you more numbers to average, so any one day matters less.
What if the number gets me down?
For most people there's no link between weighing and mood35, but for some it can feel heavy6. Weigh yourself less often, look only at the average, and talk to your GP if it's taking up a lot of headspace.
What time of day should I weigh myself?
In the morning after the loo, before you eat or drink. That keeps conditions the same each day, so the numbers can be compared.
Sources
- Steinberg DM et al. Weighing every day matters: daily weighing improves weight loss and adoption of weight control behaviors. J Acad Nutr Diet, 2015
- Steinberg DM et al. The efficacy of a daily self-weighing weight loss intervention using smart scales and e-mail. Obesity, 2013
- Zheng Y et al. Self-weighing in weight management: a systematic literature review. Obesity, 2015
- Madigan CD et al. Is self-weighing an effective tool for weight loss: a systematic literature review and meta-analysis. Int J Behav Nutr Phys Act, 2015
- Benn Y et al. What is the psychological impact of self-weighing? A meta-analysis. Health Psychol Rev, 2016
- Pacanowski CR et al. Self-weighing: helpful or harmful for psychological well-being? A review of the literature. Curr Obes Rep, 2015
- Orsama AL et al. Weight rhythms: weight increases during weekends and decreases during weekdays. Obes Facts, 2014
These guides are here to inform, not to give personal advice. If you have a medical condition, are pregnant or breastfeeding, talk to your doctor or health visitor.