Your body is adjusting to a new energy source (fat vs food). Give it time. Also, ten pounds per month is a bit ambitious- I think most people on here aim for about a pound or more per week. I average losing about 5 pounds every month.
For me, it’s was one awful week, and then so-so another one.Did you count 1200kcal correctly as your daily goal? If you are in too much deficit, you will be hungry, miserable, and tired. Just saying.Be patient. If you can stick to IF, you will lose weight.
mct oil helps since it more easily breaks down into ketones your body can use to kickstart your body into fat burning mode.
if you find yourself lethargic or with frequent headaches, get in some bone broth with sea salt for electrolytes.
Electrolytes help me with energy. I take these as they also have methylated b vitamins which help with fatigue. https://www.amazon.com/Extended-Electrolytes-Himalayan-B-Complex-Vitamins/dp/B08ZYWC5Q8/ref=sr_1_6?crid=1X0N702G7LNI2&keywords=reset+electrolytes&qid=1672843231&sprefix=Reset%2Caps%2C142&sr=8-6
That’s a hard-core calorie deficit for someone your size. You could easily lose a pound or two per week if you ate 1500. The best plan is the one that you can stick to and I don’t think 1200 cal a day is realistic. I weigh 125 pounds and I’m lean, 5’6”/14% body fat/F. There’s no way I would eat 1200 cal a day! I need to eat 1800ish cal to maintain my weight and when I’m trying to lose weight (I’m not currently) I will only cut down to 1600.
I’m also super physically active and work out 4 to 6 times per week burning about 400 cal per work out. So that means I do need to eat more than a person who is sanitary. However, your TDEE (total daily energy expenditure) is probably around 2000 cal a day if you’re at least somewhat active. Did you calculate the 1200 number based on your height/weight/age & activity level, or did it just sound good to you?
There are total daily energy expenditure calculators online and they are a useful tool. They won’t get it perfect, but I cross-referenced an online calculator with the data from my Apple Watch, which tracks my workouts and activity, and got about the same number. Then, I calculated what I actually eat and these aligned pretty closely, as they should since I’m currently maintaining my weight. If you’re already going to the trouble of trying to eat 1200 cal a day, I suggest you make some more precise calculations and I think you’ll find that you can be eating a little more and still lose weight. I’m not saying you won’t be hungry sometimes but at least you won’t be starving.