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August 15, 2016

9 Reasons Why Your Weight Fluctuates Throughout the Day

9 Reasons why your weight Fluctuates throughout the Day

You step on the scale, hold your breath, cross your fingers, and hope for the best. Maybe you have a number in your head you are hoping to see on the screen. Maybe you close your eyes and open them barely enough to see that dreaded number appear. Or even better, you see the number, get off the scale, and re-measure because surely the scale was broken that first time.

I used to have a love/hate relationship with scales. I loved them when they told me what I wanted to see but I hated them when they said otherwise. I felt like smashing them on the ground into pieces (yes, I admit I did that once). Even if I felt great, one glance at a scale that said otherwise would erupt anger within me! Well not anymore...

That relationship with the scale was unhealthy. The scale is not the end all, be all. It is simply one way to measure progress. Often times, other ways are more accurate. You may be wondering how the scale could fluctuate. Well, let me share a quick story first.

9 reasons your weight fluctuates throughout the day

My client Samantha was working her butt off. She was killing it in the gym, adhering to her daily macronutrients closely, and hydrating well. Over the course of a month she was making steady progress and losing about two pounds per week. She was extremely happy with her progress and motivated to continue losing weight. However, at her fourth check-in with us, her mood went from excited to depressed. Even though her progress pictures looked better, she was hitting new personal records with her lifts in the gym, and her inch measurements went down...her weight went up two pounds. She sounded like she had lost all motivation and was ready to quit.

Poor Samantha, she let the scale take her down. As her coach, it was time to educate her on why scale weight fluctuates throughout the day and pick her back up. The key lesson: Increased scale weight may be due to temporary fluctuations and not related to body fat at all. That was the case for Samantha and sure enough, her scale weight leveled out a few days later and she was right back on track.

Keep reading as I cover the 9 most common reasons weight fluctuations occur throughout the day and from day to day.​ Plus, I share how to track your progress using other measures besides just scale weight!

9 reasons your weight fluctuates throughout the day


Your bodyweight is composed of three components:

- EBM= essential body mass

- LBM= lean body mass

- BF= body fat

You can change the last two only by changing your percentage of muscle, fat, and water. So once again, it all comes down to your daily nutrition and training. Find a solid and sustainable program, stick to it, and you will see results. Your lean body mass (muscle) will increase as your body fat decreases. Those are the percentages you’re concerned with- not water weight. Don’t forget that everyone will have around 3-5lb temporary weight fluctuations daily: that is normal. They are not temporary if you consume more energy than you burn off though.

9 Reasons Your Weight Fluctuates

    1. Food weight
    2. Carb intake
    3. Sodium intake
    4. Alcohol intake
    5. Creatine intake
    6. PMS
    7. Stress
    8. Workouts
    9. Test Parameters

    Water Weight

    Now that you know the nine possibilities, let’s talk about them in more detail.

    Food intake increases your weight- obviously. If you put a one pound burger into your belly, you are going to gain a pound of weight (unless you are magic). This is one reason you should weight yourself first thing in the morning after you use the restroom and before you eat or drink anything. It makes your measurements more accurate since you were fasting 7-8 hours while you were sleeping. It levels the playing field.

    The main cause of weight fluctuation throughout the day is water weight. Just because the number on the scale went up does not necessarily mean you gained body fat. To keep this science lesson simple, carbs are stored as glycogen in our muscles. For each gram of glycogen, 3-4g of water are stored in our body. So when we have a tough workout and eat more carbs, we retain more water. When we eat less carbs, the water weight drops. Does this mean you shouldn’t eat carbs? Absolutely not.

    (See Related: Don’t Hate the Carbs, Hate the Calorie Game)

    The same goes for sodium. When you eat more sodium the scale number is going to go up because sodium makes the body hold onto more fluid. If you were to change your diet and consume less sodium, you would lose some water weight.

    Consuming alcohol has the opposite effect. It dehydrates you and therefore decreases your water weight and your overall scale weight. Unless you consumed excessive calories with all those mixers, soda, fruit, etc. I always wondered why I lost weight after a night out drinking in college! It all makes sense now.

    Lastly, the popular supplement creatine pulls water along with it into your muscles where it is stored. Therefore it causes an increase in water weight when taking it. If you were to stop taking it, you would likely lose a few pounds of water weight.

    Quick recap: Carbs, Creatine, & Sodium are in love with water whereas alcohol pushes water out (how rude). I always have to make things lovey-dovey.

    bikini competition coach

    Thank You Mother Nature

    Many women retain more water during their period temporarily. That is because our bodies start preparing us for our period about five days before it starts. The average weight gain is five pounds but it really varies from 1-10lb. When our body realizes we are not pregnant, it retains extra water due to our hormones. Plus, we feel even bigger due to bloating (lucky us).

    Don’t worry, this water weight won’t effect long term progress. On the other hand, if we were to binge and eat extra due to period cravings (hello Oreo’s), that could definitely hinder progress and cause weight gain.

    Don’t Worry About A Thing

    Stress is something I battle with a lot. Between my full time job as a PT and my part-time job as a health & fitness entrepreneur, I am a busy bee. Just about everyday I tell myself, “I wish I had more time” because I have so many ideas and visions for my future. Stress is not good because it increases cortisol levels which causes water retention.

    Instead of stressing, I remind myself to tackle the stress monster before he takes me down: be defensive. I tackle him by taking three deep breaths, saying a quick prayer, and then re-organizing my thoughts. That may include writing a to-do list or something similar, because I am the Queen of lists. Meditation is another great idea for preventing stress.

    (See Related: Meditation)

    Just A Few More

    Working out causes an increase in water retention due to your body sending extra fluid to those muscles you just tore up in the gym, literally.

    In addition, the testing parameters effect your results. So keep them the same. Measure your weight at the same time. Right after you wake up and go pee, strip! Weigh yourself naked and before you drink any water or eat anything.

    I Tracked My Weight for 30 Days

    Here’s how my weight fluctuated alb day to day, while I was maintaining the same macros and my personal goal was to maintain weight.

    weight fluctuations are normal

    Four Ways to Track Progress

    Now that you understand how scale weight can fluctuate, you should use it as just one of four ways to measure progress. Put more emphasis on other tracking methods like body circumferential measurements, progress pictures, and how you feel. The number on the scale going UP is not always a bad thing: you may be gaining muscle but losing body fat. Checkout my transformation below: a 16lb increase but I look way healthier and stronger now.

    beautiful to the core before and after

    Four Methods:

    #1 Weight- Weigh yourself without clothes or shoes on for accuracy. Use the same scale each time. Place the scale on a hard surface. Record in pounds.

    #2 Body Circumference Measurements- Take measurements for these 6 areas: chest, arm, waist, hips, thigh, and calf. All should be taken without flexing or sucking in. For the sake of consistency, measure your extremities on the same side each time (or you may measure both sides). Round to the nearest quarter inch.

    #3 Progress Pictures- Take pictures from 3 angles: front, side, and back. You should take the pictures in the same location with the same lighting each time. Also be wearing the same outfit. You could wear shorts and sports bra or a swimsuit. Have someone take the pictures for you. If this is not an option, you could purchase a cell phone mount that suction cups to a mirror or a mini tripod and use the self timer.

    #4 How you feel- How does your body feel? How are your clothes fitting?

    In order to take the above measurements, you may need the following supplies:

    Tape measure - like this one here

    Bodyweight Scale - like these here or here

    Cell phone mount - like this one here

    Watch the video below for details on “How to Take Progress Measurements”:


    • The weight loss component you should focus your time on is lean body mass which is largely affected by your nutrition and training.
    • Weight fluctuations throughout the day are normal and should not alarm you.
    • The food, supplements, and drinks you consume throughout the day affect your water weight and can therefore alter your bodyweight temporarily. Weight gain will only last if your total calorie intake is more than your caloric expenditure.
    • Your period and stress affect your hormones which cause water retention.
    • Measure your progress four ways so you do not rely solely on scale weight. Be consistent with how you measure them.

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