Fat Cells

“Let’s Talk”: Fat Cells

As we all attempt to shrink these stubborn cells in a modern day culture that is sabotaging our efforts, I thought I’d explain how fat cells work. 

Over half of adults in the US are overweight and 65.2 percent of the U.S. population is considered to be obese. This number is rapidly rising and it’s just not acceptable anymore!

It’s important to know that your number of fat cells is determined at birth, but their size changes over time, and that is up to you!

There are two types of fat tissue:

White- We can draw energy from them, or use them as thermal and mechanical insulation. 

Brown- mostly in babies, but is responsible for heat generation when you get cold. Adults have very little. 

How do we store fat into (mostly white) fat cells? The journey begins when we consume food and we must expend energy to break down large fat molecules into smaller ones so we can use them as energy (and hopefully not store them). 


When you eat fat in food, the large droplets travel through your stomach and intestines where they are mixed with bile from your gallbladder to be broken down into smaller droplets. The pancreas excretes enzymes which break down these small droplets into glycerol and fatty acids, so they can be absorbed through the lining of the intestines. They are then turned into triglycerides where they can be released into the lymphatic system where they merge with your blood vessels and enter the bloodstream. What a journey! 

But what determines whether these triglycerides are stored in our fat cells or burned as energy? One of the key players is insulin- secreted by the pancreas when we eat, it acts as the messenger for what to do with the food once it’s digested. Insulin will always try to store fat and burn carbs and protein first, as that’s the easy option.

The good news is, if you’re healthy, when you aren’t eating, your body will release very little insulin, meaning you can burn stored fat as energy! This is one of the keys to weight loss. 

Your body will always prefer to use carbohydrates for energy first though, which includes anything you just ate as well as stored glycogen in your liver and muscles. But if you empty out these “gas tanks” you can dig into the reserves- your fat cells as part of lipolysis!

Losing weight, and particularly burning fat, is determined by the rate at which you store what you eat, use your stored energy, and how efficient you can become at using fat for fuel. Shrinking your fat cells is hard, but it can be done!