The Sink and Plumber Model of Fat Cell Regulation.

Getting people to break free of the notion that weight gain is a strict calories in versus calories out problem can be a challenge. Becoming fat is a fat cell regulation disorder first and foremost. 
Here's how I explain it using sink in my exam rooms:

A malfunctioning fat cell is similar to a clogged sink. Imagine that your bathroom sink starts filling with water instead of draining promptly when the faucet is on. You call a plumber to look at your sink.  You might be pretty mad at the plumber if he said, "Well, it looks like your sink is full. You need to use less water to balance the water in to the water out. Maybe you should bail water out with a cup." 

Your response to him should be, "Aren't you gonna unclog the drain you moron?!" 
Unfortunately, with regard to weight, most doctors' and dietitians' advice is as useless a our hypothetical plumber. We tell people, your fat cells are full. You should really eat less and exercise more. Your response should be, "Aren't you gonna unclog my fat cells?" 

A clogged fat cell doesn't release it's stored fat when the rest of the cells in the body needs a steady supply of energy between meals. The fat cell drain (scientists call it Hormone sensitive lipase) (also Known as HSL) is clogged. The hormone that HSL responds to is insulin. Insulin causes fat to enter fat cells and it also prevents it from exiting. Insulin clogs the fat cell drain. 

If you have super abnormally high levels of insulin your fat cells will be clogged and you will get fat.  Insulin resistance causes high insulin levels. 

What reduces insulin? What unclogs your fat cell drains? It's the absence of carbohydrates.  Dietary fat doesn't stimulate insulin production and doesn't cause the clog that's why it's weight loss food. 

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