1 Brain
Perhaps that long-put-off project just popped into your head. Or maybe it’s actually due – now. Either way, your brain’s fight-or-flight centre, the amygdala, hollers to the hypothalamus that there’s a threat. The hypothalamus then sends your body into battle (or bolt) mode, commanding your nervous and endocrine systems to ramp up their activity. Chronic procrastinator? Your amygdala may never rest at all, keeping you ever ready to respond to the next perceived danger.
2 Pituitary Gland
Better known as the gland that makes you grow, the pituitary sends out messenger hormones, known as ACTH and TTH, to marshal the rest of your stress response. At the same time, a hormone called vasopressin tells your body to hoard water and increase blood volume.
3 Thyroid Gland
The arrival of TTH tells your thyroid gland to pump out (you guessed it) thyroid hormones. They in turn stoke your metabolism, causing your heart rate and blood pressure to shoot up.
4 Adrenal Glands
Meanwhile, ACTH has appeared in your adrenal glands, opening the hormonal floodgates so that adrenaline, noradrenaline and cortisol pour into your body. These stress hormones prime your muscles, tax your lung function and pause all nonessential operations in order to conserve and focus resources. Eventually, daily exposure to cortisol makes you less sensitive to its effects.
5 Immune System
Since your body doesn’t know if it’s facing a lion or lymphoma, infection-fighting white blood cells begin circulating, along with a commensurate amount of cortisol to keep their numbers in check. But your delaying ways may leave you resistant to cortisol, allowing rampaging white blood cells to cause damaging inflammation.
6 Visceral Fat
Your adrenal glands require extra energy to keep pumping out stress hormones, so your body creates a reserve by packing fat around nearby organs. These stores of visceral fat will soon start to release even more inflammatory molecules. Next up: a heart attack by way of insulin resistance and elevated LDL cholesterol.
