How unnoticeable body changes affect our clothing fit

Photo by Bill Oxford on Unsplash
Jan 26, 2021
5 min read

When it comes to buying clothes, we have an idea about the size that will fit us. We stick with that size unless there are any major changes in our lifestyle. However, our bodies are not static and they change over time sometimes without us even noticing.

Everybody's body is different and it changes in accordance to our lifestyle. There are some common factors that apply to all of us when it comes to these changes. These factors are important to consider when purchasing new clothes, especially bespoke or tailor made garments. Our analysis of sizing charts used by custom-make retailers indicate that a 2 cm difference in your waist measurement means that you will fit in a completely different size category. When it comes to ready-to-wear retailers, the difference between sizes is about 4 to 4.5 cm depending on the type of clothing and material. Therefore, small changes in our body composition will inevitably affect the size of clothing that will fit us best. Let's look at how body measurements change and what to keep in mind when recording your measurements.

Evening vs morning

You would think that taking your measurements in the evening and then again in the morning won't make a difference, right? Wrong! An article by Cosmopolitan reviews an experiment carried out by Instagram blogger Lauren Tickner who took 2 photos of herself, one in the evening and then another one on the next morning. She found her body changed significantly in that short timespan. Why is that the case? I am sure you guessed by now, food. The type of food you had the night before could result in a fluctuation of 2 to 3kg (almost half a stone), affecting the body's shape and size. If you had a heavy dinner like a pizza for example which your body takes longer to digest, it is very likely that you might wake up bloated. On the other hand, a light dinner may result in weight lost, because you have digested the food and your body has dehydrated in the process. That's why sometimes you may seem slimmer in the morning compared to the rest of the day. Similar fluctuations in our bodies are very likely to occur when we change our diet, which will inevitably impact the fit of our clothes too, sometimes in a matter of days.


When we start a new training plan we normally expect to see a change in our weight, which we normally use as an indicator that our body is changing. Sometimes that doesn't happen and we start stressing out about our training plan. Weight doesn't always tell the full story. Depending on the type of training, it is very likely that our body is changing. We do not notice the changes unless we take regular measurements of the chest, waist, hips, etc. American Council of Exercise estimates that depending on age and gender, you can build up to 2 pounds of lean muscle per month. A pound of muscle and a pound of fat weigh the same, but muscle is more dense. It is estimated that a pound of fat takes 4 times more space than a pound of muscle. Therefore, although your weight might stay the same, your measurements can change significantly in the process. With targeted training plans which focus on specific muscle groups, you can achieve significant changes in as little as 30 days. In a 30 days challenge, Youtuber Laurie Shaw increased the size of his biceps by 3 to 3.5cm. If you are buying a fitted shirt, this can make the difference between feeling comfortable or ending up with a shirt that doesn't fit. During a new training plan, it is very likely that your weight distribution is changing. This will inevitably change the size of specific body measurements inevitably cascading to the clothing sizes that feel right.

It is absolutely normal for our body measurements to change over time. There are a lot of factors that influence those changes such as diet, age, sleep, water consumption, etc. We won't always recognise those changes until we buy a new piece of clothing and notice that it is a bit tight or loose. The clothes we buy are a reflection of how our body changes, but we shouldn't let these changes surprise us. With technologies such as Size Me Up, you can measure yourself before purchasing clothing so you don't end up buying something that doesn't fit. With our free online brand comparison app, you you can find your size across 6 popular UK brands and get your body measurements. You can also use our "Find my size" online widget across the partner retailers we work with. Once we produce your measurements, you can create a profile and use them across our network of retail partners. Use it as much as you like free of charge. No more surprises when buying new clothes!

By Yanko Slavov

Co-Founder, Size Me Up