Here is a science story from The Guardian:
The University of Ulster study of 4,563 adults found a strong positive correlation between housekeeping and body fat levels. People who spent the most time cleaning house also weighed the most. The researchers and reporter speculated that house cleaning is not the useful exercise that it appears to be.
But there are more direct ways to measure the effects of exercise. When you measure a person’s oxygen consumption, you have almost a direct read on how much fat burning is going on. Exercise physiologists can estimate within a factor of 2 just by watching video that shows the muscle movements of an activity. Such direct evidence of the exercise value of house cleaning can’t be abandoned for this kind of indirect evidence. And there is no need to. There is a simpler explanation.
We know that there is a toxic effect from breathing air that contains cleaning chemicals and dust. This effect is compelling enough that there are workplace safety regulations on the subject. There are no such rules when you clean your own home, yet chemicals and dust are found there too. Toxic effects lead to body fat buildup. Body fat is used to store some chemicals and minerals temporarily, for weeks or years, until the liver can decompose and encapsulate them. With more chemical stress, more body fat is needed. If housework is leading to body fat buildup, this suggests that the cumulative toxic effects of house cleaning are greater than previously thought.
I am not about to stop cleaning my house, but I will see what I can do to limit my exposure. People who do commercial cleaning all day long don’t seem to have the same risk, even though commercial cleaning chemicals are in some cases more toxic than the household versions of the same thing. The main difference, I think, is that professional cleaners don’t stay in a room they have just cleaned. They always have somewhere else to go. I know people who have the same habit at home: clean, then get out of the house for an hour. There must be something to that.