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Will a 1000 calorie deficit ruin my metabolism??

Hello :) I'm Steph, an 18 year old, 164cm, and after a few years of being unhappy with my weight I have decided to lose the last 17kgs.
I am actually going on holidays overseas in early January and I really really am hoping to lose the weight before then.
I'm playing it safe and have decided on a daily deficit of 1000 calories.
I know there are a lot of controversies, where people think it isn't safe if you're not really overweight, or it might induce eating disorders and everything like that and I know the risks and everything.

I'm deciding to eat a base of 800 calories a day, and eat back exercise calories.
30% vegetables, 20% fruits/sweeter vegetables like carrots, 30% protein, e.g. eggs, egg whites, protein powder (isolate), 20% fats/dairy.
I will juice my vegetables most days to get the maximum nutrition, vitamins and minerals without feeling stuffed.

My lifestyle is pretty sedentary, but I do workout for at least 45 minutes a day. 4 days a week I do strength training. I drink heaps of green tea, lemon+water, ginger etc to rev up my metabolism

Okay thanks for reading all that! From your past experiences or what you know, is this a safe regime to go on? Will this destroy my metabolism??
NOTE: I have 19 weeks exactly until my holiday, so I will only do this 1000 calorie deficit for 3 1/2 months.
THEN I'm going back to a normal healthy diet.


Thank you so much for your help! I appreciate it :)

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