If you want to avoid the frustration of seeing your weight fluctuate, there are a few simple things to look out for. The best place to start is gaining a deeper understanding of how and why your body stores water and glucose as extra pounds. 

Here’s what we’re about to cover:

  • Why Does the Human Body Store Fat?
  • What is Weight Fluctuation?
  • 8 Most Commonly Overlooked Causes of Weight Fluctuation

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Why Does the Human Body Store Fat?

Your body uses fat cells to store energy. If you have an excess of energy, say too many calories, they get converted to fat cells or stored in the fat cells that are already there. Fat is for long-term energy storage. If you have carbs in your system, your body will prefer to burn those first because it’s easier. When you burn fat, what you’re really doing is reducing the size of the fat cells in your body. 

Your body is surprisingly accurate at monitoring how much energy it has and sending signals to the brain to eat when energy levels are low. However, there are some things that can cause this system to malfunction, frequently leading to weight gain. These include genetic conditions, illnesses, medicines, and environmental factors such as stress. 

These environmental factors can also be fairly insignificant, which is why people so rarely notice them until they begin to cause weight fluctuation. 

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Working out can have a direct impact on fluctuations in weight.

What is Weight Fluctuation?

Just to be clear, when weight fluctuates it’s typically just a few extra pounds. Adults’ normal body weight tends to shift 5 to 6 pounds per day. If you see this happening, don’t worry too much. It’s only when you see definite weight gain or steadily lowering body weight that something bigger might be happening. 

Even though weight fluctuates by a comparatively small margin, it can still be a nuisance to weight loss programs and just monitoring your body weight in general. There are some ways you can make an effort to reduce your daily weight fluctuation, but you have to know what’s causing the weight fluctuation in the first place. 

8 Most Commonly Overlooked Causes of Weight Fluctuation

Misusing the Bathroom Scale:

Enemy of many and friend to none, the scales we use to measure our body weights are generally pretty spot-on, especially digital models. While your scale may not be lying to you per se, it’s easy to use them improperly. They should be zeroed out before each use for the best accuracy. You can always use your scale to measure a free weight to see how well it measures weight. 

Another way people misuse their bathroom scales is by weighing themselves at a different time of day each day. Your body is at its lightest in the mornings before breakfast but after a trip to the bathroom. After that, the cycle of eating, drinking, and more bathroom breaks causes your body weight to change. Once you decide what time of day you want to weigh yourself, you should keep weighing yourself at that same time consistently to avoid interference from elements of your daily routine. 

What really makes scales inaccurate is people overusing them. We’ve already mentioned how body weight fluctuates by 5 or 6 pounds per day naturally. Weighing yourself every single day is going to make you hyper-aware of this weight fluctuation. In fact, unless you’re an athlete or have a health reason for it, you can probably get away with one weigh-in per week. Monitoring your weight in between weigh-ins is as easy as monitoring whether your clothes fit.

Excessive Sodium Intake:

It’s easy to eat too much salt with the preponderance of processed foods in our society. Whether it’s canned soup or restaurant meals, there is lots of hidden sodium out there that people aren’t aware of. Eating sodium is bad enough for causing issues with blood pressure and the heart, but it also increases the body’s water retention. Water weight can impact your weight loss goals by creating negativity and discouragement. Extra pounds that stem from fluid retention can unfairly disguise the benefits of exercise and nutrition programs that are successfully burning pounds of fat.

Monitoring your diet and avoiding salty foods are great ways to reduce your sodium intake. Cooking your own meals and using fresh food as much as possible will also help. In fact, you’ll come to prefer fresh food if you can kick processed food for long enough. Potassium also helps counter the effects of sodium in the body. Nonfat yogurt, sweet potatoes, tomatoes, white beans, kidney beans, oranges, bananas, and cantaloupe are all tasty natural sources of potassium. 

Another way to counter the effects of increased fluid retention is to drink enough water. That may seem paradoxical, but it works. Having enough water helps to flush out excess sodium. You should also get enough sleep to prevent a build-up of cortisol in your bloodstream, which leads to increased water weight. Good exercise alongside proper hydration will further help your body flush out excess sodium.

The Day of the Week:

It may seem like magical thinking, but studies have shown that people typically gain some weight on the weekend and start losing weight during the week. Many people consume more calories or enjoy a few alcoholic drinks when the workweek is over, which can cause them to gain weight. Those who are dieting with weight loss in mind might reserve Sunday as their ‘cheat’ day and indulge. For many people, the weekdays are just too full of things to do to spend much time snacking.

If you’re seeing the majority of your weight fluctuation on the weekend or on Monday when the effects of the weekend are starting to show results, you should take a look at your weekend activities. It’s best to keep in mind that it takes a lot to cause noticeable weight gain in a single day – you’d have to eat thousands of calories in addition to whatever your body needs to power its various processes. Unless you’re drinking excessively, you probably won’t put on a pound in a single weekend. 

That being the case, you can definitely erase a week’s worth of weight loss by over-indulging on the weekend. That’s why many people are forsaking the cheat day in their diet plans. It’s best to follow the If It Fits Your Macros rule if you’re going to have a cheat day at all and eat extra of something you find tasty in a dish that fits your diet, rather than gorging on fried foods or alcohol. 

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Drinking Alcohol:

Alcohol consumption has many side effects, and besides the relaxing effect one or two glasses can have, the side effects are almost all negative. There are tons of useless calories in most cocktails and beer is full of carbs. That doesn’t mean you can’t have an occasional drink, but there’s no way to reconcile regular binge drinking and a healthy lifestyle. If weight loss is your goal, drinking booze can be a double whammy. Not only are the drinks themselves likely to be high in calories, but people are also less reserved with their food choices when they’re under the influence. Bars typically serve fried foods that are high in fat, cholesterol, and sodium, a perfect storm for your body if eaten regularly. 

One thing that alcohol also does is cause you to urinate more often. Because there’s so much extra water in your body when you have many drinks, your body may panic to deal with it. The calories in alcohol cannot be stored by your body the way other calories can be, so your body will prioritize alcohol calories before food calories. That may sound great at first, but it is likely to cause your body to turn the calories you get from food into fat and cause weight gain. 

Just like it’s pretty difficult to take in enough calories in a single day to gain a pound of fat, it’s unlikely that most people drink enough to have it be the sole cause of weight fluctuation. But drinking alcohol can exacerbate the effects of other factors like water weight and sodium intake and cause frustrating weight fluctuation. 

Hormonal Changes:

There are many things that can impact your hormone levels. Stress and sleep are two of the biggest reasons people find their hormones out of whack. Many people are familiar with stress eating and a sneaky cocktail after work when they’re feeling stressed. These can cause weight gain, but stress also increases the amount of cortisol in the bloodstream, slowing metabolism and digestion. Relaxation is important if you find yourself frequently stressed to the point of exasperation. Classic tricks to reduce stress like baths, meditation, and massage all help, but you can also use other tactics that will help you meet your fitness goals like yoga and exercise. 

Another important hormone that can cause weight fluctuation is called leptin. This hormone is produced by fat cells and acts as a signal to the brain that there is enough energy stored in the body. When levels of leptin fall, the body feels hungry so we eat to give it more energy. The biggest problems with leptin are when your body builds a resistance to it. This is most common in obese people whose bodies produce so much leptin that they become desensitized to it, causing them in turn to eat more which only makes the problem worse. 

Insulin can also have an effect. Most people are likely already aware that diabetes has something to do with insulin, but even without diabetes, insulin levels can be off and cause weight fluctuation. This could happen because of sugar consumption, but it can also be an effect of too much cortisol, the stress hormone we spoke about earlier. 

Foods that are heavy in carbs such as bread, potatoes, and pasta can lead to weight gain.

Eating Carbs:

We’re not about to vindicate the no-carb crowd here, but eating a ton of carbs can also cause some weight fluctuation. If you do try a low- or no-carb diet, you’re more likely to lose lots of weight at the beginning because your body doesn’t hang onto water when you eat tons of carbs. However, you’re also more likely to gain that weight back when you reintroduce carbs into your diet. It’s much more likely you’ll be successful if you measure carbs as one of your macros, rather than cutting them out entirely. 

Your body has to retain water in order to store carbohydrates as energy. So if you suddenly have an Italian pasta feast, your body might take on some water weight in addition to the weight of the pasta itself. The good news is that since this is water weight, it can also disappear again quickly, which is not the case if you put on some extra pounds of fat. You might have to put some extra work in at the gym to burn through the glucose your body creates out of carbs, but you can still eat that pasta. Just don’t freak out if the number on the scale is higher the next day.

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Menstrual Cycle:

Those who have one are familiar with the bloating and weight gain that happens at that time of the month. Putting on a few extra pounds during your period is extremely common, but it’s normally due to fluid retention and not from stacking on new pounds of fat. Typically this weight will go away after the menstrual cycle is over. There are also hormone changes during a period, especially with the hormones estrogen and progesterone, which your body uses to handle fluid retention. That’s why bloating and increased puffiness in the breasts, extremities, and stomach is so common during the menstrual cycle. 

Just remember that the weight gain during your period is not real weight gain but simply water weight. It’s more important not to completely abandon your diet in favor of whatever foods you have a craving for during the menstrual cycle. That can lead to real weight gain if you overindulge. Of course, even if you do give in to your cravings, it’s nothing you can’t work off in the gym later on. 

Working Out:

That’s right, even though it can be a solution to many of the other causes of weight fluctuation, lifting weights and working out can also make your weight fluctuate. This is because your muscles tear when you strength train or otherwise put a strain on them. The human body builds muscle as it heals these muscle tears with satellite cells. This process is fairly complicated to understand, but it takes water to perform. The muscles retain water to make sure the muscles can be repaired, which is why your muscles look so pumped up right after a workout. If you’re doing regular strength or resistance training, make sure your diet has enough protein and other nutrients needed to support the extra muscle growth. 

If you work out regularly, it’s wisest to have your weigh-in before you exercise. Otherwise, you might see your weight fluctuate a few pounds as your muscles retain extra water and mistake it for a failure. Of course, building new muscle will also increase your body weight, so your overall weight should increase when you train for a long time. Just remember that it’s not new body fat you’re putting on. Muscles are exactly the kind of weight you want to have on your body. 

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Seeing the numbers on the scale decreasing in the middle of a weight-loss routine or going up when you’re trying to build muscle is a thrilling validation. But seeing the scale oscillate several pounds for seemingly no reason is easily one of the most frustrating things that can happen even if you’re just living through your normal routine.

There are many things that can cause weight fluctuation, not the least of which are long-term programs for weight loss and general fitness. These cause weight change over periods of time. Everyday weight fluctuations are caused by a wide variety of smaller actions and conditions that many people overlook when they’re trying to get rid of the few extra pounds that suddenly appeared on their scale. It’s easy to control for the causes of weight fluctuation once you know what they are.

It probably won’t require a huge shift in your diet or workout plan, but there are a few simple things you can do to reduce the likelihood that your weight fluctuates. Some of these tactics are just good advice for fitness in general, like limiting your sodium intake and not completely abandoning your diet on the weekends. However, it’s also important to understand that your body weight will fluctuate as a result of your body’s natural processes and an extra pound here or there is nothing to worry about. Besides, sudden slight weight gains today are frequently gone by tomorrow. 

There are many factors that affect your overall body composition and cause weight fluctuation. Eating a big meal or having an excessive sodium intake, for example, can both lead to increased fluid retention, which will build up water weight. Maintaining an adequate water intake to stay hydrated can help your body flush out things that lead to weight fluctuation. 

Hormone changes can also cause you to see a slightly higher number on the bathroom scale. These can be caused by a menstrual cycle or by environmental factors like stress or sleep. The bottom line is that your normal weight is not a fixed number but rather a range that includes typical weight fluctuations. There are plenty of things you can do to reign in weight fluctuations, but you aren’t ever going to figure out a way to completely keep it from happening. The best you can do is watch your diet and exercise regularly so your body can get rid of additional weight quickly when it does appear. 

If you need help formulating an exercise program, our professional trainers are happy to help. 

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