Stress & Energy Regulation...

Discussion in 'Fibromyalgia Main Forum' started by COOKIEMONSTER, Jul 20, 2003.



    "Why Zebras Don't Get Ulcers"
    By Robert M. Sapolsky

    Stress and Energy Regulation (Metabolism)

    Digestion is the process of breaking down the food we eat into the simplest parts. These parts end up as amino acids, simple sugars, and free fatty acids. It takes a lot of energy to do this efficiently, but it is important in order to store energy and nutrients for future use. After a meal, all the parts are floating around in the blood stream, waiting to be used or stored.

    To understand this a bit better, consider finances. You get your paycheck. You can either cash your paycheck and carry the cash or you can store it in the bank until it is ready to be used. Most people will store their extra money in the bank. And usually not just in a bank account, if there is a lot of it. Most people with a fair amount of money will invest in Mutual Funds, the Stock Market, or Savings Bonds.

    The same goes for food parts. It is stored in fat cells or in other cells as glycogen. Insulin is the hormone responsible for storing energy compounds in cells. It is like the deposit slip for the bank. The body will secrete it when you eat or when it is anticipating a meal. If you eat at the same time every day, your body will start secreting Insulin in anticipation of that meal before you even start eating.

    When you eat proteins, they are converted into amino acids, then stored as proteins and released as amino acids during a stressful event.

    When you eat carbs, sugar and starch, they are converted into glucose, stored as glycogen and released as glucose during a stressful event.

    When you eat fats, they are converted into fatty acids and glycerol, stored as triglycerides and released as fatty acids, glycerol and ketone bodies during a stressful event.

    When you have plenty, your body stores the extra. The process of storing energy takes a lot of time and energy, something you don't have during an emergancy. In the face of a physical emergancy, your body needs every bit of energy available to meet the crisis and save your life. Storage of energy comes to a complete halt and stored energy is released with the release of glucocorticoids. The production and release of insulin is stopped, and the glucocorticoids, glycogen, epinephrine, and norepinephrine reverse the storage process that insulin has been doing. Non-exercising muscles will lose some protein, exercising muscles that are saving your life are spared from losing any protein.

    Amino acids are not good sources of energy, so they are shunted to the liver which generates new glucose from then in the process calle Gluconeogensis. As a result, lots of energy is available to meet the emergancy and save your life.

    Glucocorticoids and other stress hormones will block the uptake of energy by any cells. However, exercising muscles have some sort of mechanisme, unknown to date, that blocks that effect and allows the uptake of energy to let them keep working efficiently.

    So with all this energy regulation going on, why does stress make people sick?

    Well, if the stress is constant or frequent, it uses a lot of extra energy to do all the converting and simple fatigue sets in.

    To use the financial analysis once again -- suppose you put $10,000 into an IRA. You need to leave it there until you are 59 1/2 years old or you will be charged a penalty. Well, you need the money before then, so take it out and use it to meet immediate expenses, and then replace the money you actually used. But you had to pay a penalty for that use. Before too long, you need some more money and take some out once again. You have to pay another penalty, even though you replace it. Soon you have lost all the money to penalties and have none left in your account.

    Another consequence is the loss of protein from non-exercising muscles under the influence of glucocorticoids. Repeated stress will cause a small amount of muscle atrophy. Use of large amounts of administered glucocorticoids can actually cause a wasting away called steriod myopathy.

    Finally, this can trigger the development of one of two types of diabetes. The first type is insulin-dependant, when the pancreas cells that make insulin are destroyed by an autoimmune response. Without insulin, the cells starve, which causes big trouble all over the body.

    The other type of diabetes is insulin-resistant, when the pancreas is making enough insulin but the fat cells have lost their sensitivity to insulin and will not accept any more energy storage. This most commonly occurs when the fat cells have reached storage capacity and cannot accept any any more. This is a disease of inactivity and fat surplus, not a disease of aging.

    The challange for any diabetic is trying to maintain a balance between insulin and blood sugar. If the sugar levels get too high, the cells are unable to use it and it will build up and start to clog the vascular system, which in turn causes problems through the body. If the sugar levels get too low, the cells starve and damage is likely to occur.

    So how does stress play a role in this? First of all, the stress hormones raise blood sugar levels for quick energy and if there is already too much blood sugar, this makes things worse, causing more vascular damage. Then the stress hormones promote insulin resistance, making fat cells less sensitive to insulin effects even when the stress has passes. When additional steriods are administered, they can cause "steriod diabetes".

    During non-stressful times, most diabetics have everything under control. Blood sugars are rather stable, they know how much insulin to add, how much food to eat and how much to exercise to maintain this balance. Add some stress to the mix and everything changes. The normal dose of insulin is no longer effective and the stress raises the blood sugar. So they increase the dose of insulin to get things back in balance, then the stress is over and they are getting too much insulin, making blood sugars drop too low.

    For the insulin-resistant person, stress can trigger the diabetes. You may be older, with a bit of extra weight and just on the edge of blood sugar imbalance. Along comes some stress which makes you more insulin resistance and the blood sugar soar out of control. This sets you up for vascular problems, maybe a heart attack or other problems.

    The stress does not have to be physical stress to cause problems. Psychological stress will cause the same problems with metabolism as physical stress, maybe more, as you don't have the energy burn-off fighting or flighting. This shows the double-edged nature of the stress-response and the consequences when it is prolonged.

    Anne M., RN