Your Hormones Start Inside Your Cells' Energy Engines

Inside nearly every one of your cells sit tiny compartments called mitochondria. Stephanie Crasweller, who leads Vitality OET, a company focused on fat loss and women's hormones in perimenopause and postmenopause, likes to call them little engines.

They earn the name. They combine fuel from fat or carbohydrates with oxygen, and convert it to ATP, the chemical energy the body runs on. They produce over 90% of the energy the body runs on. Crassweller says they are the only place where fat is actually used as fuel. They also help make hormones, help run the brain, and help decide how fast you age.

That hormone job is more direct than most people expect. Every steroid hormone, meaning estrogen, progesterone, testosterone, and cortisol, starts out as cholesterol, which is why Crasweller says the body needs enough cholesterol in the diet. As Crasweller puts it, "the very first step of turning that cholesterol into a hormone happens inside of your mitochondria." Nothing later in the chain can happen until that step is done.

So a damaged engine is not just an energy problem. When mitochondria slow down or get damaged, the body makes less energy, burns less fat, and runs into what Crasweller calls "one of the major roadblocks in being able to produce hormones in the first place." The link runs in both directions: struggling mitochondria make hormone production harder, and hormones in turn affect mitochondria. Energy falls, brain fog thickens, hormones worsen, and weight becomes harder to lose, which is one reason protecting the engines also protects hormone supply.