I felt like I was dying?

1200 is not enough food for most people. The feeling like absolute crap for a few days then feeling better may also be related to you cutting something out to reduce calories, like a large amount of caffeine or sugar. You have withdrawal like symptoms for a few day then get over it.

When I made up my mind to lose weight last year, I started with the recommended lose-two-pounds-a-week-eat-1200-calories thing, and I think I lasted two weeks. As soon as I bumped it up to lose 1.5 pounds a week, I felt more energetic. After I lost about 15 pounds, I changed my goal to lose 1 pound a week. When Ih ad 15 pounds left, I set my goal to lose .5 pounds per week. I've lost 43 pounds so fat and am trying to learn maintenance, which is all trial and error.

Always eat enough to fuel your body. The weight will come off, but the less you weigh the longer it takes to get it off. Patience is a virtue.

Any sudden drop or fluctuation in calories will cause hormonal disruptions, sleep disruptions, mood swings, and a protective response from the body - most people binge back their calories within two weeks of starting a diet, and end up heavier than before. Any sudden change in food intake - even if it's still above weight maintenance - will produce side effects as your body adjusts.

1200 calories is too low for most people unless you're inactive, have a lot of weight to lose and want to do it quickly. I lost most of my excess weight at 1200 calories, although I was tired a lot of the time. As the weight dropped and I exercised more, 1200 became miserable. These days I am careful to hit maintenance because even small deficits will produce some side effects, poor exercise performance, and very possibly binge eating. I can't tell you how many days I cut 500 calories to get ahead of the game, then binged 1200 over maintenance the following day, and didn't feel full at all. It was an absolute waste of time.

I'm reading about the Ansel Keyes starvation experiment and learning a lot about the the psychological effects of dieting - and how prolonged restriction can hurt the body's ability to maintain a normal weight. The men in the experiment were put on starvation diets to take them significantly below a healthy BMI. The subjects became socially withdrawn, obsessive, neurotic about small details of exercise and food, miserable, with no sex drive. When the subjects returned to normal eating, many binged and did not feel full no matter how much they consumed. They lost some muscle mass and ended up heavier than their starting weight. Most eventually lost the excess over a period of months after the experiment, without trying to diet.

You can lose weight fast at first, but maintenance is the real annoyance.

Your body will get used to the calories if you give it a week or more - but try 1500 and see if that's less annoying. There's no way around the side effects, that's just a product of weight loss.

1200 calories is not enough to sustain most people. Eat more like around 1400