Comment: There are better explanations...

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There are better explanations...

People do not get fat by eating it. They get fat by not being able to burn it. And, that is 100% controlled by hormones, namely leptin and insulin.

...the mobilization of fat from adipose tissue is inhibited by numerous stimuli. The most significant inhibition is that exerted upon adenylate cyclase by insulin. When an individual is in the well fed state, insulin released from the pancreas prevents the inappropriate mobilization of stored fat. Instead, any excess fat and carbohydrate are incorporated into the triacylglycerol pool within adipose tissue.

BTW, dietary fat does not stimulate the secretion of insulin. In the absense of dietary glucose, you burn fat when you eat fat.