8 Reasons Why Weight Fluctuations Are Totally Normal

If you’re going to weigh yourself and pay attention to the numbers, it’s important to understand all the little fluctuations. Spoiler alert - it’s typically nothing to worry about.

Erin Fisher Author Image
Erin Fisher

July 22, 2024 - Updated July 22, 2024

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Optimum health, wellness and vitality looks different on everyone, using BMI as a health indicator has been challenged in recent years for very good reason, and obsessing over your weight isn’t good for anyone, but we also know that the scales can still be a helpful and encouraging tool for many people.

For those who are on a weight loss or weight management journey, using the scales can be a simple way to figure out if your lifestyle habits are making a difference. The hard part is - especially if you’re working towards a specific goal - not getting too caught up in the constant fluctuations in the numbers. Your weight is going to go up and down because everyone’s weight fluctuates. And generally, it’s absolutely nothing to stress about.

Here are eight reasons why your weight might jump around a little bit and how to set yourself up for a healthy relationship with the scales if you plan on using them.

Eating and drinking

The first obvious one is that every single thing you eat or drink weighs something, so it’s only natural that after each meal or beverage, you should expect your weight to increase slightly. Guzzling 500ml of water is still 500 grams, even though staying hydrated offers plenty of health benefits and won't effect your daily calorie intake. That in itself is the perfect example of why small fluctuations shouldn’t stress you out.

Fluid retention

While we’re on the topic of eating and drinking, your body can also hold onto more water depending on what you’ve eaten. Salty foods, simple sugars, alcohol and high-carbohydrate meals can all cause increased fluid retention, affecting the number on the scales depending on when you decide to weigh yourself.

Exercise

The fluid lost through sweat and breathing during exercise can bring your weight down slightly, or if you drink a lot of water mid-workout, it might push your weight up. If you’re following a strength training program, increased muscle mass is something worth celebrating, but that too can show up as weight gain on the scales. Depending on your goals and journey, it might make more sense for you to use photos or a journal of how you feel and perform to gauge your progress.

We will always encourage you to exercise for the myriad of health benefits that go beyond weight, and weighing yourself post-workout isn’t a good habit to get into. The numbers will move around a lot, and the last thing we want is for you to judge the success of your workout by what the scales say.

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Hormones

Throughout your menstrual cycle, fluctuating hormone levels can impact your appetite, food choices and weight. Research has shown it’s common to experience increased cravings and calorie intake during the luteal phase, and you may also notice bloating or fluid retention at different points. At other points of your cycle, your appetite and bloating may decrease, along with your weight.

These ebbs and flows are normal and aren’t something to fight against - your body is incredibly intelligent and trying to ignore your own hunger signals is only going to leave you feeling worse. If your weight over a year was shown on a graph, you might notice lots of monthly dips and peaks up close, but see it’s pretty steady when you take a step back.

Bowel movements

Just like the scales go up when food goes in, the scales go down when it comes out, and this has nothing to do with your fitness progress or body composition.

Sleep quality

Nope, we aren’t talking about midnight snacks here, but your sleeping habits can affect your appetite! According to the Sleep Foundation, a good night’s sleep promotes the healthy production of hormones like leptin and grehlin, which regulate your appetite and fat storage. If you’ve ever noticed your stomach is growling more and your cravings are through the roof after a terrible night’s sleep - it’s not a weird coincidence, there’s science behind it! A lack of sleep can impact those hormone levels and cause you to feel hungrier than normal.

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Weekend fun

Unless you’re very strict with your diet, most people have a little more fun with their eating habits over the weekend when socialising, dining out or simply treating yourself - yes please. Experiencing joy and having meaningful social connections are both such an important part of a healthy lifestyle and should never be something you deny yourself. If anything, it might mean simply changing when you weigh yourself.

Research shows that weekend lifestyle changes can contribute to weight changes, but unless you’re really overdoing it each week, it’s nothing to panic about. Other research investigating weight rhythms highlighted that weight variations between weekdays and weekends are normal, with weight being highest on Sunday and Monday and decreasing again throughout the week. Don’t let the short-term fluctuations bother you and instead focus on your long-term habits.

Medication and illness

Some medications such as antihistamines and anti-inflammatories can cause weight loss, while other medications like antidepressants and insulin can lead to weight gain. Different medications, illnesses and health conditions can stimulate or suppress your appetite, so if you’ve noticed a significant change in your weight while being on medication or are concerned about the possibility of another health condition, it’s always best to chat to your healthcare professional for advice.

When should you weigh yourself?

If you find the scales a helpful tool that you have a healthy relationship with - power to you! The main thing to remember is that it’s normal for your weight to have small fluctuations throughout each day, week and month. Take a general overview of the numbers, and always weigh yourself at the same time with the same scales. The Cleveland Clinic recommends weighing yourself naked or in the same clothes first thing in the morning after you’ve used the bathroom.

On the other hand, if you have a history of disordered eating, obsessing over numbers, negative body image or simply don’t feel like regularly weighing yourself is a good or necessary thing for you, feel free to ditch the scales. Whether or not you have physical goals, there are plenty of other ways to measure your health and wellbeing.

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Keep seeing the bigger picture

The scales measure your weight. That’s it. They don’t measure your overall health, vitality, fitness, mental wellbeing, strength and happiness. So see the numbers for what they are and take this as your permission slip to use the scales if they work for you and your goals, or use a completely different yardstick to measure your success. Healthy looks and feels different to everyone.

Erin Fisher Author Image
Erin Fisher

Erin is a writer and editor at Sweat with years of experience in women's publishing, media and tech. She's passionate about the power of movement, and you can often find her on a yoga mat, a hike, a dance floor, in the ocean or the gym.

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* Disclaimer: This blog post is not intended to replace the advice of a medical professional. The above information should not be used to diagnose, treat, or prevent any disease or medical condition. Please consult your doctor before making any changes to your diet, sleep methods, daily activity, or fitness routine. Sweat assumes no responsibility for any personal injury or damage sustained by any recommendations, opinions, or advice given in this article.

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