How Much Does Weight Fluctuate in a Typical Day

how much can your weight fluctuate in a day

Daily Weight Fluctuation- Why Does It Happen?  

If you weigh yourself regularly, or perhaps every morning, you most likely will have noticed daily weight fluctuation.  

Differences in weight day-to-day is very common and is often a result of eating a particularly big meal or drinking a lot of water (weight gain,) or not having a big workout and losing a lot of sweat, or not eating as much as usual (weight gain)

How much can your weight fluctuate in a day is mostly due to what we put into our body, and what comes out of it. 

Is Weight Fluctuation Normal?  

Weight fluctuation in a day is very normal and not something you need to be concerned about. Of course, if you notice a shift in weight that is significant, there could be a more serious reason, but generally, weight loss as a result of a health concern is gradual and will take several weeks.  

Normal weight fluctuation can be the result of:  

  • Water retention caused by increased sodium intake, carbohydrates, and some medications.
  • Eating an increased amount of food. E.g. If you put a pound of food in your body, you're going to weight an extra pound until that food is processed.
  • Losing water through sweating and urinating

How Much Can Your Weight Change.

How much can your weight fluctuate in a day greatly differs from person to person, a weight change of around 5lb (plus or minus) is often considered normal, but this number can rise to approximately 20 pounds in larger individuals.

Usually, the heavier you are to start with, the more the fluctuations in weight can be. If you follow a lifestyle that follows little routine in terms of eating, drinking, and activity, you will likely see greater fluctuations in weight as well. 

daily weight fluctuation

Weight Fluctuation Over A Week.  

Weekly fluctuations in weight are not temporary as daily ones are. Over the course of a week, a real change in physical weight is possible, as opposed to just a fluctuation in what's going in and coming back out.  

If you eat are regularly consuming more calories then what you are burning off in a day, you can expect to see some degree of weight gain over a relatively short period.  

The same goes for consuming fewer calories than what you burn off in a day, except having a calorie deficit will result in weight loss.

A weight loss of around 2lbs a week is considered healthy and safe, any more than this amount can see you feeling the negative effects of rapid weight loss, which includes muscle loss, nutrient deficiencies, and a slower metabolism.  

Weight fluctuation in a week can be the result of lifestyle habits, such as drinking more alcohol one week, resulting in weight loss from dehydration. As a whole, however, weekly weight changes are usually more cemented and based on body composition as opposed to daily ones.  

If you are tracking bodyweight weekly and are seeing small fluctuations, it can be a good idea to change your weighing schedule to a daily one, in order to see if you experience similar variations over a shorter period.

Other Factors Impacting Weight Change.  

So we've covered daily weight fluctuations, and gone over why one can see weekly weight fluctuations, but what other factors can impact bodyweight?  

Bodyweight is made up of many different things, many of which are variable, meaning that they can change.  

The most frequent changes are body fat, muscle mass, and water weight.  


how much can your weight fluctuate

Muscles are amazing at adapting, and they never like to be any bigger then they have to be. So, if you lift a lot of weights and put your muscles under strain, muscle mass will increase, which in turn will increase body weight.

If you don't put your muscles under much stress and live a rather sedimentary lifestyle, muscle mass will decline, resulting in a drop in body weight.   


Although fat is often seen as bad, body fat is incredibly important for the health and functionality of the body.

As well as being good for keeping the body warm, body fat is also the body's back up reserve of energy. When in a calorie deficit, the body dips into these fat stores to keep on functioning, resulting in weight loss.

But when there is a surplus of calories, the body stores what it can as fat to use at a later date.  


Up to 60% of an adult's body weight is made up of water, so it is not hard to see how fluctuations in hydration can significantly affect the overall weight of the body.

The more hydrated you are, the more your body will weigh; however, if you find yourself passing excessive amounts of urine, or not replenishing your fluids adequately, bodyweight will decline significantly.