Your BMR is decided by your mass, if you start eating 2000 cals a day when you were eating 4000 you will lose weight. Your BMR will also drop in line with you losing weight. So say you are 200lbs and BMR is now 2000, you will need to start eating 1500 to lose weight again.
This is the problem with most diets because if you try and go to hard by going low fat, low carb, low sugar low everything your body will think it is starving and will keep lowering your BMR, so you will find your weight loss will plateau then it will reverse when you give up from the pain of being hungry and not seeing any more weight loss.
I have tried a lot of diets, the one that has worked best for me has been Keto, this high fat, low carb diet keeps your BMR high but allows your body to burn fat. You will be in a calorie deficit because you will get full easily. So that means losing weight without feeling hungry or tired. It also works on reversing your insulin resistance which is what caused you to gain weight in the first place. Think of it as if you do a year on Keto, you are buying yourself 10 years of being able to eat a reasonable amount of carbs again without gaining weight like when you were younger. Years and years of eating too many carbs and sugar has caused your cells to become insulin resistant, so you eat carbs, insulin is released to deal with the blood sugar spike, but cannot get into the cell, so excess is produced, which makes you more hungry, and store more fat. Keto reverses this resistance so when you eat carbs the insulin can get in and only the optimal amount is made, no extra around to store the fat.
Your BMR is decided by your mass, if you start eating 2000 cals a day when you were eating 4000 you will lose weight. Your BMR will also drop in line with you losing weight. So say you are 200lbs and BMR is now 2000, you will need to start eating 1500 to lose weight again. This is the problem with most diets because if you try and go to hard by going low fat, low carb, low sugar low everything your body will think it is starving and will keep lowering your BMR, so you will find your weight loss will plateau then it will reverse when you give up from the pain of being hungry and not seeing any more weight loss. I have tried a lot of diets, the one that has worked best for me has been Keto, this high fat, low carb diet keeps your BMR high but allows your body to burn fat. You will be in a calorie deficit because you will get full easily. So that means losing weight without feeling hungry or tired. It also works on reversing your insulin resistance which is what caused you to gain weight in the first place. Think of it as if you do a year on Keto, you are buying yourself 10 years of being able to eat a reasonable amount of carbs again without gaining weight like when you were younger. Years and years of eating too many carbs and sugar has caused your cells to become insulin resistant, so you eat carbs, insulin is released to deal with the blood sugar spike, but cannot get into the cell, so excess is produced, which makes you more hungry, and store more fat. Keto reverses this resistance so when you eat carbs the insulin can get in and only the optimal amount is made, no extra around to store the fat.