What is "set point theory"? are toxins involved? describe how body size and homeostasis are related?

Set point theory suggests that our body has a particular range of weight that it is comfortable in, usually about 10% of a body’s weight. That means, if you weight 175, you have about an 18 pound range; if you weigh 325, you have about a 33 pound range. Most people lose and gain within this set point on a pretty regular basis. They may put on a little weight in the winter and lose it in the spring. Or get busy and drop a little weight. Or gain a little when stressed. Or lose a little during an illness. Or whatever. Movement within this range is normal. However, movement outside of that range is not. In fact the body seeks homeostasis – that is the body seeks to stay within that range. To move outside of that range something must go on, something must happen to the body.

What's the question?

Your answer is water because there is combined mass of water found on, under, and over the surface of a planet. your answer is water.