What happens when you consume 3,000 calories a day depends on the relationship between its caloric intake and consumption. When the intake of calories is much greater than the consumption of calories, the human body will experience weight gain, and even lead to obesity and so on.
General 60 kg of adult women under light physical labor one day consumption of calories for about 1800 calories, 60 kg of men under light physical labor one day consumption of calories for about 2100 calories.
Consuming 3,000 calories a day is considered excessive calorie intake for most people. Excessive calories are easily converted into fat, resulting in weight gain, which can lead to obesity in the long term.
But for some special people, such as heavy laborers, sports athletes and teenagers in the rapid growth stage, a day of 3000 calories is just a balance of calorie income and expenditure, so it will not bring additional burden to the body.
To summarize, how many calories the human body intakes a day depends on many factors such as age, exercise status, growth and development, gender and so on. So different people need to make a calorie intake plan according to their specific situation.