You've seen it happen. You stay strict on an eating plan but your weight seems to be stuck. And then, all of a sudden, WHOOSH you lose a few pounds. Is it caused by your fat cells holding water?

First, let's start with the basics. Your body has fat cells - adipocytes - which store the fat in neat little circles in your body. Each fat cell has its supporting structure and then a "chamber" where the fat lives. You generally don't lose fat cells (with a few exceptions). You're born with a certain number which then fill or unfill as needed. Most dieters are aiming to unfill them.

Let's also remind ourselves that oil and water don't mix. You've probably seen this with oil-and-vinegar salad dressing. The oil layer stays separate from the water layer until you shake them up.

There are some on the web who feel, therefore, that water only stays out of fat cells when those cells are full of fat. They have a theory that when the fat cells empty out, suddenly water flows into those fat cells, keeping them round. And that it's only later on, when that water empties out for some reason, that the body will WHOOSH and lose weight.

However, this is not proven to be true.

Rather, in talking to a number of researchers who specialize in how fat cells work, they indicate that a fat cell is never truly "empty" in the sense of a gas tank having not even a drop of gas left in it. If it was, we would look like those tragic photos of starving children in the Sahel region of West Africa. That is not what most people who have internet access look like. Rather, we have fat cells which are perhaps "gently stocked" even at our "healthy weight" levels. There is still at least a small reservoir of fat in each cell. And, like oil and water, that reservoir would not let water in.

That is if water even had a tendency to randomly flow into cells it finds, which it doesn't. It would be quite unhealthy if water in our body had a natural desire to flow into and balloon out cells it came across.

Certainly, fat cells have a mechanism by which they fill and empty. For example, this study in The American Journal of Clinical Nutrition discusses how triglycerides, cholesterol, and tocopherol leave fat cells at different rates.
The American Journal of Clinical Nutrition Study on Fat Cells

But water simply does not go INTO them.

So what DOES cause that WHOOSH of weight loss, if it doesn't involve water being mystically trapped in fat cells and then released?

Glycogen, Water, and the Whoosh Weight Loss Effect



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