I have read in several threads about people questioning if someone has ruined their metabolism from starvation diets. My question is this, how do you know if you have ruined your metabolism/ if you have is there anyway to correct it, or what is the best way to work around that?

1. I highly doubt you can ruin your metabolism.

2. You can certainly slow it down by under eating chronically, however, even this fact is overblown around the web.

3. 15 calories per pound of bodyweight is the average for maintenance, meaning, energy in = energy out and you maintain your weight. If you were to eat that and feel very full or gain weight, chances are, you have slowed down your metabolism from under eating. If this is the case, and you are having trouble losing currently, I would suggest small, systematic increases in caloric intake back toward your natural maintenance. I have done this with clients with little to no fat gain. Other gain some fat during the process, but it is a necessary short term evil for a long term good.

Like Steve already said, you can't easily 'ruin' your metabolism. Metabolism being the speed of the chemical reactions in your body, so I'm assuming you're speaking of the chemicals and hormones that regulate these. While trying to lose weight you need to keep your metabolism naturally high as possible while avoid too sharp and frequent insulin spikes. Following a VERY low calorie diet will cause your body to naturally inhibit the release and production of various endogenous hormones including thyroxine and triiodothyronine, which will cause your weight loss to slow and cease once a point is reached. Which is why carb/calorie cycling is so successful and suggested.