Your Body on Stress … It’s Not Pretty
I mentioned that stress creates some powerful chemical changes in the body. If we look at some of those chemical changes from the point of view of weight gain and inability to lose weight you can see that stress has a huge influence on our metabolism.
- increased output of cortisol
- increased output of insulin – continuous exposure to increased levels of insulin will eventually lead to insulin resistance, improper management of glucose, and … fat storage
- decreased calorie burning capacity – no matter how little you eat or how much you exercise, when in stress response calorie burning is reduced
- less blood flow to the gut – digestion shuts down completely – your body needs blood supply to your legs and arms for fight or flight, not to be digesting a meal
- die-off of healthy gut bacteria
- heart rate and blood pressure go up
- increased LDL (bad) cholesterol, while good HDL cholesterol levels drop
- decreased thyroid hormone – affecting a host of processes in the body including metabolism
- decreased testosterone hormone – leads to muscle loss and fat accumulation – and yes ladies, you too have some testosterone
- excretion of all minerals and water-soluble vitamins – your requirement for nutrients is greatly increased during times of stress
Most importantly, excess cortisol and insulin signal the body to store weight, store fat and not build muscle. Why not build muscle – because muscle burns more calories and takes up more resources and in times of stress those resources are needed elsewhere. Stress chemistry also turns off digestion so you can eat the healthiest food in the world but if it is eaten in any degree of stress you will not be digesting the full nutritional value of that meal. How many times have you eaten when you are feeling stressed about something?
Cortisol is the main stress response hormone and it is responsible for setting off the entire chain of physiological events during a stress response. When cortisol is released into your bloodstream you become less sensitive to a hormone called Leptin which is the hormone that tells your brain when you are full from food. Then you tend to eat more and crave more sugar. This is not some cruel joke by your body, it makes perfect sense. After dealing with running away from the tiger you need to eat all you can and store energy so you are ready for the next tiger.
Unfortunately for us, cortisol also causes us to store fat around our bellies. We are starting to learn a lot more about fat – both dietary fat and fat in the body. We now understand that fat cells are not just storage depots for energy but communicate with our hormone system and send out messages to the body regulating weight, metabolism, stress hormones and inflammation. So it is a vicious cycle where weight gain and stress feed each other.
Stress chemistry signals your body to hold onto weight.
This was an important survival mechanism when we lived in times of feast and famine. It’s less helpful today when we have access to high-fat, high-sugar, low nutrient foods on every street corner, every hour of the day.
In Anti-Stress Eating Strategies I’ll discuss some things you can do to create less stress around food.