The egg is not 'lost' the egg is released during ovulation, if not fertilized then it is reabsorbed into the body. Ovulation typically occurs two weeks before menstruation, but everyone is different.
Calories are not lost during chronic diarrhea. Critical nutrients and water are lost during chronic diarrhea which can lead to dehydration.
For the menstrual cycle to happen, it requires calories for the body to functin and for the muscles to work properly. There are also many nutrients that are lost in the tissues and blood that are expelled during a period, as those nutrients would have been needed if a baby was to be supported. In anorexics, there is usually a large defecit of calories. In order to save vital nutrients and energy for survival, the body stops the menstrual cycle. It is viewed as "unnecessary" (unlike lung or heart functions, for example, which are needed to survive), and so it is stopped until normal weight and food inatke resume once again.
Well, you've "lost" 200 calories. Or your body has used 200 calories worth of sugar, fat, or protein.
Prolonged diarrhea can cause weight loss. If enough weight is lost, it can affect reproductive hormones enough to make the menstrual cycle irregular.
The average amount of blood lost during menstruation is around 30-40 milliliters, which is roughly 2-3 tablespoons. This can vary from person to person and cycle to cycle. If you are concerned about the amount of blood you are losing during your period, it's best to speak with a healthcare provider.
There are no calories in water
524 calories
Being skinny, or losing a lot of weight, shouldn't affect your menstrual cycle unless it's a very drastic change. When you become very skinny, your body decides that it's 'not fit' to have a baby, so it halts the production of eggs, and hence the uterine lining, which is what you shed (blood) during menstruation. No eggs, not uterine lining, no period. So unless you lost A LOT of weight and were OVERLY active, odds are you wouldn't have any problems.
One pound = 3500 calories. Decreasing calories by 500 per day for a week = 3500 calories lost or 1 pound.
The blood lost during menstruation comes from the uterine lining that had built-up over the coarse of the woman's menstrual cycle, it doesn't come from a womans main blood supply. As long as a woman is healthy there is no loss from menstruation, and nothing needs to be done to 'recover' anything.
It is NOT true that during the water cycle, water disappears. Water constantly moves through the cycle, transitioning between its various forms (liquid, vapor, ice) without being lost.