In general, every person will normally consume 1500-2000 calories per day. In any case, a person's total calorie intake should not be less than 1,200 calories per day.

To lose weight, you must just keep the calories you consume every day to be greater than the calories you take in.

Expanded:

The human body uses energy every minute of every day, and this energy is provided by the thermogenic nutrients in food. Calorie-producing nutrients in food are proteins, fats, sugars and carbohydrates. They are oxidized to produce heat for the body to sustain life, growth and development, and exercise. When calories are supplied in excess, the excess calories are turned into fat and stored, and over time, the body puts on weight.

The nutrients that provide calories in the diet are sugars (carbohydrates), fats, proteins, alcohols, and organic acids. The calories they contain, measured per gram, are: 4 calories from sugars (carbohydrates), 9 calories from fats, 4 calories from proteins, 7 calories from alcohol, and 2.4 calories from organic acids.

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