What you need to know about sudden weight fluctuations

It goes something like this ….

Aubrey watches a 60 second Facebook video about how effective low-carb diets are. Maybe Aubrey’s friend starts a low -carb diet and drops a dress size in a week. Aubrey is then fully convinced that carbs are an invention of Satan himself so decides to treat them as such.

Aubrey cuts out carbs altogether and abracadabra, she drops 8 pounds in 2 days! It’s a miracle!

But there’s a problem. Aubrey is able to stick to her low-carb diet for 6 days, but on the 7th, she goes out to dinner and adds and tucks in to the mash potato. The next morning Aubrey is devastated! She weighs herself expecting to see more weight off, but instead she’s found that she’s put on 3 pounds!

What’s going on?!

This isn’t an exception! So many dieters are confused and embarrassed when they see on the scales that they’ve somehow gained 2-3 pounds overnight. Some people even as much as 6 pounds!

How can this be? Can your weight really fluctuate so much in such a short space of time?

If we’re talking about weight, the answer is yes. And it’s very likely to happen on a regular basis.

If we’re referring to pounds of fat and lean tissue, the answer, is a definitive no!

So what is actually happening here?

Water and Salt

If you’ve ever had a Chinese meal or a Pizza (and I know you have! I always know what you’ve been eating. Just kidding) you might have noticed the next day that you feel a bit bloated, a bit heavier.  Well, that’s because you are.

This is mostly due to 2 main causes

1) your digestive system hasn’t had time to process the large meal you’ve consumed.

2) the excess sodium you’ve consumed has caused your body to retain extra water so it can keep your electrolytes balanced.

Your body will rectify both of these issues in the next 24-48 hours and it will go down the toilet, in some form or other. However, the scales will only tell you that your weight has gone up 3 or 4 pounds but they won’t tell you that it’s water and not fat that’s increased.

Glycogen and Fluid

Glycogen is stored in carbohydrates in your muscles and liver. For every 1 gram of glycogen it’s accompanied by 3-4 grams of water. If you dramatically reduce your carbohydrates, your muscles will store less glycogen and therefore less water.

How much can glycogen affect weight? 

Let’s say you weigh 155 pounds (11 stone / 70kg). You could lose as much as 3 pounds (1.36kg) of weight in just a few days if your glycogen stores have been depleted, merely from a lack of carbohydrates. If you combine this with intense exercise and you weigh more than 11 stone, this number will only increase. It’s really not hard to see how weight fluctuations can and do happen along the way. This of course is not fat tissue reduction, but glycogen and water that has been depleted from your muscles and liver.

Fluctuations Throughout the Day

WHEN you weigh yourself will impact your scale weight as well. Some people jump on the scales at random times without tracking the time of the weigh in. It’s best if you can keep it consistent.

What typically happens throughout the day? Bowel movements! This is something we often fail to recognise but it will affect your scale weight, along with the amount of food and drink you’ve been eating along with the sodium content within those foods and drinks.

What’s the answer?

Perspective is important when it comes to monitoring scale weight. It’s crucial to have as much data as possible when tracking progress. This is why I insist upon using a range of measurements to monitor progress instead of using scale weight alone.

Think about:

  • Tape measurements – waist, chest (for guys), thigh girth, arm circumference
  • Progress pictures
  • BMI (Body Mass Index)
  • Body Fat Percentage
  • Fitness tests
  • How your clothes fit

All of these help build a broader picture over time of your progress, instead of celebrating 3 pounds off on Monday, then bemoaning 5 pounds on by Sunday. They’re also a healthier way of measuring true progress.

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