Bone Marrow, The Tymus - The Players In The Immune System : Part 1

UltraLongevity: The Seven-Step Program for a Younger, Healthier You
by Mark Liponis, M.D.

Do you want to live the longest, healthiest life possible? Do you want to stop aging? Better yet, do you want to reverse aging?

According to the latest scientific research, you can control the aging process, simply by paying attention to one thing: your immune system.

That's right. All you have to do is manage your immune system, because every disease of aging, and in fact aging itself, has been shown to be associated with an overactive immune system.

In UltraLongevity, Dr. Mark Liponis, medical director of the world-famous Canyon Ranch Health Resorts, presents this revolutionary new paradigm for the first time. He explains the science behind this extraordinary idea, and shows how the immune system can lead to aging and all aging-related diseases, including heart disease, cancer, and diabetes.

Dr. Liponis also offers an innovative and practical seven-step program that not only gives you guidelines for a healthier life; it reveals some startling facts about aging. Did you know that big meals send the immune system into overdrive? That women who sleep six hours or less per night are 20 percent more likely to suffer heart problems? That rhythmic exercise is more helpful to the immune system than other kinds of exercise?

Along with an eight-day meal plan and more than fifty delicious recipes from Canyon Ranch's celebrated kitchen, UltraLongevity will help you stay sharp, keep fit, and feel younger than you ever imagined. Dr. Liponis promises more than a long life; he promises a long, healthy life.

Chapter 1

Inside you are more than thirty different organs, which include more than two hundred different cell types and about 100 trillion cells. Each organ is patrolled by your immune system, which is constantly performing surveillance for possible threats. Following are some of the major players.

Bone Marrow

Bone marrow, the reddish-looking material inside nearly every bone in the human body, is where all of the blood cells are produced.

Inside the marrow, on an inner framework, lie the bone marrow stem cells. These cells are constantly dividing, producing huge numbers of cells that turn into red and white blood cells.

The bone marrow stem cells continue to divide, even as they keep making red and white blood cells. And just as a couple of million are being produced every second, the same number are being gobbled up and destroyed in the spleen, which is, in effect, the cells' decommissioning center. The spleen is where blood cells are taken out of circulation once they've completed their useful life cycle (see below).

This process-birth in the bone marrow, death in the spleen- should be evenly balanced. If it isn't, you will be prone to a blood disorder. For example, if your system is destroying more red blood cells than it's making, you'll become anemic, which will make you feel tired and appear pale. If you're making more than you are destroying, you'll become polycythemic, or suffer from blood that is overcrowded with red blood cells.

Once the cells form in the bone marrow, they remain there and mature, at which time they exit and enter the bloodstream. There they circulate, the red cells carrying oxygen and carbon dioxide, and the white cells patrolling for invaders.

The Tymus

The thymus, located in front of your windpipe in the upper chest region, is the most mysterious organ in your homeland.

In infants, the thymus is, relatively speaking, huge. It grows until about puberty and then starts to shrink. By old age, the thymus has almost completely disappeared.

The thymus serves the role of a kind of boot camp for the white blood cells called T cells-it's where these cells go to mature. The thymus is especially active early in life because, during youth, T cells are constantly being exposed to new things, from new proteins in your diet to new germs. These T cells need to have a place to congregate, share information, and learn about threats and attacks.

For example, let's say one of the cells in your immune system comes in contact with a foreign invader. It now has to communicate that information to other cells so they can become aware of the invader too. The thymus is where this information is shared and training occurs.

Why does the thymus later atrophy? Science doesn't know for certain, but as you grow older, your immune system has less to learn. So the current thinking is that there may be less need for a large thymus as we age. But although the thymus is not as big or as active as it was when we were young, the smaller thymus is still able to help train T cells well into our eighties, nineties, and beyond.

The Spleen

Another important training center and meeting ground for the immune system is the spleen. This large organ, about the size of your fist, is located on the left side of your belly, tucked under your ribs.

The spleen is a common meeting place for all the immune system's cells. Blood routes to the spleen, where the cells circulate and mingle, allowing them to tell each other what they've learned, what they've seen, what they've killed, and what antibodies they've made.

The heart pumps the blood around the body about once every minute, which means each blood cell might find itself in the spleen about 1,400 times a day. That's a great many trips.

The spleen is also important because it's where the body decides if a red or a white blood cell has gotten too old. Once the decision is made, the cell is decommissioned and disassembled and its building blocks are recycled.

You can live without a spleen; if it ruptures, the liver can take over its functions. Still, if your spleen is removed or no longer works, your immunity becomes impaired; people without a spleen are more susceptible to infections.

Lymphatic System

Nearly everyone knows about the bloodstream: it's a road map of blood vessels that allow our blood to circulate through our body. But few people realize that another important, and completely different, circulatory system exists in the body-the lymphatic system, which circulates our lymph.

Lymph is a clear fluid that travels through your body, cleaning your tissues and keeping them nourished. Just as blood circulates back to the heart through our veins, lymph must also be recycled and return to the heart, which it does through the lymphatic system.

The lymphatic system is something of a secondary transportation system for your homeland troops. Like the circulatory system, it is composed of a series of vessels and tubes. The major difference between the circulatory and the lymphatic systems is that the latter lacks a pump to move the fluid it carries. For the blood, that pump is the heart. For lymph, the flow back to the heart is achieved through a more passive process involving muscle contractions and gravity.

© 2007 by Mark Liponis, MD

About the Author

Mark Liponis, MD, is the medical director of the Canyon Ranch Spa in all its locations. He is the coauthor of New York Times bestseller UltraPrevention, which won the 2003 Books for a Better Life Award in the health category.