It is depends on your age, height, weight, and sex. An office working lady needs less calories compare to a worker working under the sun.
Ways to calculate how much calories you need a day.
Male: [66 + 1.38 x Weight (kg) + 5 x Height (cm) – 6.8 x Age] x activities
Female: [655 + 9.6 x Weight (kg) + 1.9 x Height (cm) – 4.7 x Age] x activities
Activities are different for different people. Normally it will range from 1.1 – 1.3. The greater the activities, the higher the figure. 1.1 is for a normal office working lady, and 1.3 is for higher activities people.
After you get the figure of calories your body need, you should study the food calories book. If it is inconvenient to bring along the book while you are on meal, always remember, eat 60-70% full for your every meal. Besides, avoid those spicy foods, fried foods and all meat meal. Follow the food chart for your everyday meal, you will slowly get a healthy body weight.
Pregnancy
It is very important to know that pregnancy is not the time to restrict calories and carbohydrates. It can have serious risk to your growing baby if you plan to loss weight at this moment. Besides, gaining too much weight is also not good both baby and mum. Try to have your balance diet to minimize all those unnecessary risk.
You should know that pregnant lady need extra 300 calories a day. This is important for the 2nd and 3rd trimester of pregnancy. Besides, low carbohydrates and high protein diets are not allowed during pregnancy. This is to prevent low blood sugar during pregnancy. Low carbohydrates meal can also make it harder for the adsorption of vitamins and mineral needs for the mother and her developing baby.