Hi if you want to lose weight then you need to know what to eat eg macronutrient balance of protein, fat, and carbs. And how much you eat eg calories.
Here are the 3 macronutrients
PROTEINS - have 4 calories per gram
FATS- have 9 calories per gram
CARBOHYDRATES - have 4 calories per gram
Here is how you work you calorie intake
One gram of protein per pound of your ideal body weight. Multiply this number by 4 for the number of protein calories you should eat each day.
3 to .5 grams of fat per pound of your ideal body weight. Multiply this number by 9 for the number of fat calories you should eat each day.
To determine your carbohydrates you need to play about with it a bit till you fined out what suits you everybody is diffrent. You will also need to work out your BMR.
BMR Basal Metabolic Rate, You need to use an online calculator BMR Calculator
You type in you age, height, weight and then it gives you your BMR.
You then Multiply this number by your activity level to determine your calories.
Harris Benedict Formula
To determine your total daily calorie needs, multiply your BMR by the appropriate activity factor, as follows:
If you are sedentary (little or no exercise) : Calorie-Calculation = BMR x 1.2
If you are lightly active (light exercise/sports 1-3 days/week) : Calorie-Calculation = BMR x 1.375
If you are moderately active (moderate exercise/sports 3-5 days/week) : Calorie-Calculation = BMR x 1.55
If you are very active (hard exercise/sports 6-7 days a week) : Calorie-Calculation = BMR x 1.725
If you are extra active (very hard exercise/sports & physical job or 2x training) : Calorie-Calculation = BMR x 1.9
This number is the total number of calories you need in order to maintain your current weight.
Reducing calories by 15-20% below your daily calorie maintenance needs is a useful start for losing weight.