Losing fast - is this normal?

If you go from a much higher intake, especially with a lot of sodium, you will notice that. Be careful, because 1200 might be unsustainably low. You don't want to crash and yoyo.

The first couple of weeks usually mean weight drops rapidly - as you lose water weight and glycogen stores. It will slow so don't be disheartened.

I am currently on day three of eating 1200 calories/day. before I started I was 164, Day two was 160, and today I weighed 157.4...

Is it normal to lose so fast?

I'm not logging the full weight change until it's a couple of days old, but... is this normal? I was expecting to lose 1lb a week like this, which is also what MFP predicted will happen...

Help!

you're just shedding some excess water. it'll come back. your body is constantly fluctuating in overall weight due to water retention. i presume your goal is to lose fat, not just losing weight. 1200 is likely too low a calorie goal for you, unless it's a NET 1200 per day. don't weigh yourself every day, it'll frustrate you. those extra lbs coming off now will show back up on your scale next week and if you don't understand what's happening, it could cause you to panic.