The recommended calorie intake for women varies based on age and activity level. Image Credit: Sahil Miyani/iStock/GettyImages

Everything you eat and drink, with the exception of water, has calories. On the other hand, everything you do, from breathing to running to cooking dinner, burns calories. One important part of living a healthy lifestyle is balancing the calories you consume with the number of calories that you burn. When that ratio gets out of whack, you might gain too much weight or lose too much weight, both of which can lead to health problems down the road.

Estimated Calorie Intake for Women

The Dietary Guidelines for Americans, 2015-2020, lays out recommendations for caloric intake based on gender, age and activity level. Men generally need to eat more calories than women, and those who are active need more food than those who are not. Additionally, caloric needs generally decrease as you age.

Women age 18: 1,800 (sedentary), 2,000 (moderately active), 2,400 (active)

1,800 (sedentary), 2,000 (moderately active), 2,400 (active) Women age 19-25: 2,000 (sedentary), 2,200 (moderately active), 2,400 (active)

2,000 (sedentary), 2,200 (moderately active), 2,400 (active) Women age 26-50: 1,800 (sedentary), 2,000 (moderately active), 2,200 (active)

1,800 (sedentary), 2,000 (moderately active), 2,200 (active) Women age 51-60: 1,600 (sedentary), 1,800 (moderately active), 2,200 (active)

1,600 (sedentary), 1,800 (moderately active), 2,200 (active) Women 61 and older: 1,600 (sedentary), 1,800 (moderately active), 2,000 (active)

Understanding Activity Levels

Everyone's ideas of what constitutes a sedentary lifestyle versus an active lifestyle differs. For the purposes of these calories estimates, the CDC defines each as:

Sedentary: The only physical activity you get is through the daily activities of independent living.

The only physical activity you get is through the daily activities of independent living. Moderate active: Physical activity is equal to walking 1.5 to 3 or more miles a day at 3 to 4 MPH, plus the activities of independent living.

Physical activity is equal to walking 1.5 to 3 or more miles a day at 3 to 4 MPH, plus the activities of independent living. Active: Physical activity is equal to walking more than 3 miles per day at 3 to 4 MPH.

Daily Calorie Intake for Females

If you're the type that loves crunching the numbers, use a formula to calculate your total daily energy expenditure (TDEE), which takes your current weight and height into account. Your TDEE refers to the number of calories your body burns on a daily basis, and it's influenced by the energy your body needs to digest food, the fuel you use during physical activity, and the calories you burn on a daily basis through basic bodily functions, a number known as your resting metabolic rate (RMR).

When you know your TDEE, you know how many calories you need to eat on a daily basis to main your current weight.

Calculating Your TDEE

First, calculate your RMR by following this formula: (9.99 x bodyweight in kilograms) + (6.25 x height in centimeters) - (4.92 x age) - 161. Next, multiply your RMR by the appropriate activity score: 1 if you're sedentary, 1.12 if you do 30 to 60 minutes of low- to moderate-intensity physical activity a day, 1.27 if you do 60 minutes or more of moderate-intensity physical activity a day, or 1.45 if you do 60 minutes of moderate-intensity physical activity and up to 60 minutes of high-intensity physical activity a day.

The resulting number is your TDEE and equal to the number of calories you should strive to eat each day. A quick example: A woman who is 35 years old, weighs 150 pounds, stands at 5 feet, 7 inches tall and is lightly active would need to eat 1,578 calories.

Calories During Pregnancy

There are certain points in a woman's life where she should eat more to support her biological functions, so the normal calorie intake for a female can change. For example, it's no surprise that a pregnant woman needs to eat more calories while growing a miniature human inside of her. However, the exact number will vary because the appropriate weight gain — anywhere from 11 to 40 pounds — depends on a woman's body mass index prior to pregnancy.

Have a conversation with your doctor about the proper number of calories for you to aim for each day, though the Academy of Nutrition and Dietetics recommends a general estimate of 2,200 to 2,900 calories daily that's made up of a variety of nutrient-rich foods.

Read more: How to Lose Body Fat During Pregnancy

Caloric Intake While Breastfeeding

A woman who is breastfeeding generally needs to consume between 450 and 500 additional calories a day. This means that a woman could be eating up to 2,900 calories a day if she's between age 19 and 25 and lives an active lifestyle.

Breastfeeding women are often also trying to lose weight after giving birth. However, limiting caloric intake during this time could affect milk supply. Additionally, breastfeeding mothers have nutritional needs, including at least two to three servings of protein a day, three servings of vegetables, two servings of fruit and whole grains such as whole-wheat breads and oatmeal. Breastfeeding women might also need to increase their water intake to satisfy thirst and produce milk.

Calories for Weight Loss

Calorie-counting is a tried-and-true, although often tedious, tactic for losing weight. Although a variety of factors play into how easily a person sheds pounds, the basic equation is simple: Burn more calories than you consume.

One pound of fat equals about 3,500 calories, so a person needs to cut that number of calories from their diet to shed 1 pound of body fat. This can be done through a combination of burning calories with exercise or eating fewer calories.

Balancing Exercise and Diet

The number of calories to eat for weight loss depends on how quickly you want to lose weight. To lose 1 pound each week, you will need to burn or cut 500 calories a day.

Check back on the TDEE. For the sample 35-year-old woman with a daily goal of eating 1,578 calories a day, cutting out 500 calories per day strictly from her diet would mean aiming for fewer than 1,100 calories daily.