It's a brave thing, when you're out in the world practicing, to ask questions.
So many times, we think we have to have all the answers.
There is no blame, no shame in not knowing something--after all, that is a condition quite easily addressed by accurate information.
No matter where you are in your study and in your career, I hope that you never stop asking questions. If you are unclear on something, chances are there are many other people who are also unclear, but who are afraid to speak out and ask.
"Now I'm really confused. Lymphedema is toxic fluid?"
No worries--you're raising a very good question. I hope that by the end of our discussion, you don't feel confused any more.
Lymphedema is a condition.
It results when too much fluid builds up in the tissues, because--for whatever reason--the lymphatic system cannot keep up with the demand put on it by the cells releasing their waste products for the lymphatic system to carry away.
If someone has lymphedema, then you know that the lymphatic system cannot keep up, but that is not enough information for you to know *why* the system cannot keep up. There are many different diseases, syndromes, mechanical causes, and other things that can cause lymphedema.
For example, I had cancer of the uterus. The surgeons saved my life by taking out my uterus, my cervix, my Fallopian tubes, and my ovaries.
Along with those major organs, they also took out lymph nodes. Now, as a result, I have lymphedema in my legs, because the surgery that saved my life also removed abdominal and inguinal lymph nodes.
Think about what the jobs of the lymph nodes and lymphatics ducts in the abdominal and inguinal areas are. They drain lymphatic fluid from the legs, right?
So when they are removed, they can't do their job. Think about what would happen to the garbage cans on your block if the garbage collectors were no longer there. The houses (cells/tissues) would continue to put out their garbage (fluid), but it would just stay stacked up there and accumulate (lymphedema), because no one ever took it away.
So that's what lymphedema is--a condition that results from some cause (there can be many) in which the lymphatic system can no longer carry the waste fluids away from cells/tissues fast enough, and the fluid accumulates.
Cancer did not directly cause my lymphedema. Cancer caused me to need surgery, and the surgery took out some of my lymph nodes that drain my legs, and so I have lymphedema as an indirect result of my cancer.
Other people living with lymphedema will have other stories, so just to know that someone has lymphedema does not tell you why they have it.
So what's in these metaphorical "garbage cans", the lymph fluid that carries wastes away from cells and tissues?
The largest component, obviously, is fluid--when it's inside the cells, it's called intracellular fluid. When the cell is done with it, and it's ready to be transported away, it passes out of the cell and into the space between cells.
It looks the same, and it contains the same things, but at that point, it's called interstitial fluid, because it lives in the interstices, or the spaces between cells.
It is made up of water, proteins, glucose, clotting factors, triglycerides, white blood cells, metabolic waste products, and other things, depending on what kind of cell it came from, and what happened to that cell--was it healthy, injured and recovering, dying, or what?
Are any of those things toxins? No, they are not. If you really have toxins in your tissues, you should be getting medical care to treat it, not just walking around with "toxins" in your body.
But what happens when the kidneys fail, and metabolic wastes build up in the blood to levels that doctors call "toxic"? Does that mean that metabolic wastes are toxins?
No, the waste products built around nitrogen molecules are not toxins in themselves; when they are at normal levels, the body handles them just fine.
As Paracelsus said, "Alle Ding' sind Gift, und nichts ohn' Gift; allein die Dosis macht, daß ein Ding kein Gift ist.--All things are poison, and nothing is without poison; only the dose permits something not to be poisonous./The dose makes the poison."
Even water will kill you if you drink enough of it. So does it then make sense to say that water "is a toxin"?
No, because water is not inherently poisonous. Nor are metabolic wastes. They are not inherently poisonous at normal levels of function.
Only things that are inherently poisonous at normal levels of function, like botulin toxin, or bee or snake venom, or ricin from castor beans are toxins.
So a bee sting is painful or ricin will kill you at normal levels of function--they are toxins.
Metabolic wastes or water or lymph fluid are not toxic at normal levels of function--only if another underlying problem causes them to become too much for their environment--and so they are not toxins.
It's a real biochemical difference, although there is no bright and shining line in how they can be applied--look at how botulin toxin is used in medical treatments, for example.
But a good rule to go by is if it is naturally produced by cells, it's in the right place (not from outside you, like bees or botulin, but in you, from your own cells), and it's not toxic at normal levels of function, then it's not a "toxin".
Source: http://upload.wikimedia.org/wikipedia/commons/5/53/Skull_and_crossbones.svg accessed 8 July 2012