How Many Calories Should I Eat Based On My Bmi? Most of us want to lose weight, no matter if it’s a few pounds or more, and dieting is the most popular way to achieve this goal. Most dieting plans claim they’ll help you achieve your goal weight in a given period, but they are not always easy to follow.
To make things easier for you, I’ve gathered useful information on how many calories should you eat based on BMI – Body Mass Index. The estimated calorie requirements vary depending on your age, gender and activity level. The following tables provide the estimated calorie requirements for adults.
Measuring BMI for adults, children, and teens
Body mass index, or BMI, is a measure of body size. It combines a person’s weight with their height. The results of a BMI measurement can give an idea about whether a person has the correct weight for their height.
BMI is a screening tool that can indicate whether a person is underweight or if they have a healthy weight, excess weight, or obesity. If a person’s BMI is outside of the healthy range, their health risks may increase significantly.
Carrying too much weight can lead to a variety of health conditions, such as type 2 diabetes, high blood pressure, and cardiovascular problems.
A weigh that is too low can increase the risk of malnutrition, osteoporosis, and anemia. The doctor will make suitable recommendations.
BMI does not measure body fat directly, and it does not account for age, sex, ethnicity, or muscle mass in adults.
However, it uses standard weight status categories that can help doctors to track weight status across populations and identify potential issues in individuals.
BMI in adults
Calculating BMI involves measuring a person’s height and body weight.
Metric
- To calculate BMI in metric units, use the following method: BMI = kg/m2
- So, to calculate an adult’s BMI: Divide their weight in kilograms (kg) by the square of their height in meters (m2)
Since most people measure height in centimeters (cm), divide height in cm by 100 to get height in meters.
Imperial
- When using imperial units, the formula is: BMI = lbs x 703/in2
- In other words: Multiply a person’s weight in pounds (lbs) by 703. Then divide by their height in inches, squared (in2)
To avoid using the math, a person can use a calculator or a chart to find their BMI.
BMI charts
People can also work out their BMI using a chart. Click here to see a chart provided by the National Heart, Lung, and Blood Institute (NHLBI).
Locate your height in inches on the side of the chart, then look across to find your body weight in pounds. Scan to the top to see if the result corresponds to a normal weight, overweight, or obesity.
Understanding the results
The following table shows standard weight status categories associated with BMI ranges for adults.
| BMI | Weight status |
|---|---|
| Below 18.5 | Underweight |
| 18.5–24.9 | Healthy |
| 25.0–29.9 | Overweight |
| 30.0 and above | Obese |
BMI of less than 18.5
A BMI of less than 18.5 indicates that you are underweight, so you may need to put on some weight. You are recommended to ask your doctor or a dietitian for advice.
BMI of 18.5–24.9
A BMI of 18.5-24.9 indicates that you are at a healthy weight for your height. By maintaining a healthy weight, you lower your risk of developing serious health problems.
BMI of 25–29.9
A BMI of 25-29.9 indicates that you are slightly overweight. You may be advised to lose some weight for health reasons. You are recommended to talk to your doctor or a dietitian for advice.
BMI of over 30
A BMI of over 30 indicates that you are heavily overweight. Your health may be at risk if you do not lose weight. You are recommended to talk to your doctor or a dietitian for advice.
BMI in children and teens
In adults, BMI values are not linked to age and are the same for both sexes.
However, measuring BMI in children and teens is slightly different. Girls and boys develop at different rates and have different amounts of body fat at different ages. For this reason, BMI measurements during childhood and adolescence take age and sex into consideration.
Doctors and other health professionals do not categorize children by healthy weight ranges because:
- they change with each month of age
- male and female body types change at different rates
- they change as the child grows taller
Doctors calculate BMI for children and teens in the same way as they do for adults, by measuring height and weight. Then they locate the BMI number and person’s age on a sex-specific BMI-for-age chart. This will indicate whether the child is within a healthy range.
Calculator and charts for child and teen BMI
The Centers for Disease Control and Prevention (CDC) have produced a calculator that provides BMI and the corresponding BMI-for-age percentile on a CDC growth chart for children and teens.
Next, use the charts to see if a child’s weight is suitable for their age.
Click here for the charts:
- Girls aged 2 to 20 years
- Boys aged 2 to 20 years
What do the results mean?
The following categories explain the meaning of the results:
| Weight status category | Percentile range |
| Underweight | Below the 5th percentile |
| Healthy weight | 5th percentile to less than the 85th percentile |
| Overweight | 85th to less than the 95th percentile |
| Obesity | Equal to or greater than the 95th percentile |
How Many Calories Should I Eat Based on My Bmi
Your body mass index, or BMI, can help you determine your calorie needs for the day. Of course, your individual needs are based on your weight management goals. Although BMI is a good general estimator of body fat, it isn’t accurate in every case. A women with lots of muscle, for example, might weigh above the “ideal” range but still have very little body fat.
Determining BMI
If your BMI is less than 18.5 you’re considered underweight; BMIs of 18.5 to 24.9 are within a normal range, while 25 to 29.9 is classified as overweight. BMIs of 30 or above are categorized as obese. To calculate your BMI, multiply your weight in pounds by 703; divide that number by your height in inches, then divide by your height in inches again. For example, a 130-pound woman who is 5 feet-4 inches tall has a BMI of 22.3, which is within a healthy, normal range.
Weight Maintenance
If you’re BMI is within a normal range and you want to maintain your weight, you can use the calorie-per-pound method to estimate calorie needs. Harvard Medical School advises that sedentary women need about 13 calories per pound of body weight per day, moderately active women require about 16 calories per pound and women who exercise regularly at high intensities need about 18 calories per pound. For example, a 130-pound, moderately active woman needs about 2,080 calories a day to maintain her weight.
Weight Loss
About 64 percent of women in the U.S. have BMIs of 25 or greater, which classifies them as overweight or obese, according to Weight Control Information Network. There are several ways to estimate your calorie needs for weight loss. If you eat 500 to 1,000 fewer calories each day, you’ll lose 1 to 2 pounds per week. The U.S. Department of Health and Human Services notes that most overweight women need 1,000 to 1,600 calories a day to achieve weight loss, depending on their current body weights and physical activity levels. The University of Washington estimates that eating about 10 calories per pound of your ideal body weight can help you reach your weight loss goal.
Weight Gain
If your BMI is less than 18.5, ask your doctor if weight gain is appropriate. The trick to gaining weight healthfully is to increase muscle by exercising regularly — especially resistance training — and boost calories from nutritious foods. The Academy of Nutrition and Dietetics recommends eating an extra 200 calories per day to gain lean body mass. To avoid feeling too full or bloated when eating more food, get your extra calories from high-calorie, nutrient-dense foods, such as nuts, seeds, peanut butter, hummus, avocados or vegetable oils.
Estimated Calorie Requirements
Estimated amounts of calories needed to maintain energy balance for various gender and age groups at three different levels of physical activity. The estimates are rounded to the nearest 200 calories and were determined using the Institute of Medicine equation.
| Gender | Age (years) | Sedentaryb | Moderately Activec | Actived |
|---|---|---|---|---|
| Child | 2-3 | 1,000 | 1,000-1,400 | 1,000-1,400 |
| Female | 4-8 9-13 14-18 19-30 31-50 51+ | 1,200 1,600 1,800 2,000 1,800 1,600 | 1,400-1,600 1,600-2,000 2,000 2,000-2,200 2,000 1,800 | 1,400-1,800 1,800-2,200 2,400 2,400 2,200 2,000-2,200 |
| Male | 4-8 9-13 14-18 19-30 31-50 51+ | 1,400 1,800 2,200 2,400 2,200 2,000 | 1,400-1,600 1,800-2,200 2,400-2,800 2,600-2,800 2,400-2,600 2,200-2,400 | 1,600-2,000 2,000-2,600 2,800-3,200 3,000 2,800-3,000 2,400-2,800 |
a These levels are based on Estimated Energy Requirements (EER) from the Institute of Medicine Dietary Reference Intakes macronutrients report, 2002, calculated by gender, age, and activity level for reference-sized individuals. “Reference size,” as determined by IOM, is based on median height and weight for ages up to age 18 years of age and median height and weight for that height to give a BMI of 21.5 for adult females and 22.5 for adult males.
b Sedentary means a lifestyle that includes only the light physical activity associated with typical day-to-day life.
c Moderately active means a lifestyle that includes physical activity equivalent to walking about 1.5 to 3 miles per day at 3 to 4 miles per hour, in addition to the light physical activity associated with typical day-to-day life
d Active means a lifestyle that includes physical activity equivalent to walking more than 3 miles per day at 3 to 4 miles per hour, in addition to the light physical activity associated with typical day-to-day life.
What is the problem with BMI?
BMI is a very simple measurement. While it takes height into consideration, it does not account for factors such as:
- waist or hip measurements
- the proportion or distribution of fat
- the proportion of muscle mass
These factors can affect health. For example, high-performance athletes tend to be very fit and have little body fat. They can have a high BMI because they have more muscle mass, but this does not mean they weigh too much for their height.
Another limitation of BMI is that it does not distinguish between people of different ethnicities. Studies have shown that at the same BMI, non-Hispanic white, non-Hispanic Black, and Mexican Americans may have significantly different levels of body fat.
This inaccuracy may lead to a misdiagnosis or an incorrect assessment of risk factors between individuals.
BMI can offer a rough idea of whether or not a person is at a moderate weight, and it is useful for measuring trends in population studies.
However, it should not be the only measure for an individual to assess whether their weight is ideal.
Other measures of a healthy body
BMI is a useful tool, but it cannot identify whether a person’s weight is made up of muscle or fat.
For example, an athlete with a lot of muscle tissue may have a higher BMI than a person who is not very active. But, this does not mean that the athlete is overweight or unhealthy.
In addition, cardiovascular disease and high blood pressure are more likely to occur in people who have additional fat — known as visceral fat — around their middle rather than their hips.
Other measures of body size include waist-hip ratio, waist-to-height ratio, and body composition, which measures body fat and lean body mass. These measurement systems focus more on the amount of fat a person has and its distribution around the body.
Together with BMI, these additional measures can help to assess more accurately the health risks associated with an individual’s weight.
Benefits of Calorie Counting
1. Helps you Identify if you are Eating Enough
Undereating is a habitat that can form right underneath our noses. Many people find out through calorie counting that they are actually undereating.
This can especially happen if you drink a lot of tea or coffee (yes, I am talking to my iced coffee and/or tea lovers). These drinks are naturally appetite suppressors as they make you feel more full therefore eating less food. Not only can the replacement of food with these drinks cause undereating but many other factors. Whether you have a super busy schedule, a picky eater, or have an underlying health condition counting calories can be a useful tool to guide you.
To start, you can learn how many calories you need every day through calorie calculators online. Remember to always consult your doctor or nutritionist before implementing changes into your diet.
Calorie Calculators:
- Mayo Clinic Calorie Calculator
- Body Building Calculator
- Calorie Deficit Calculator
- Weight Gain Calculator
Once you have identified your maintenance calories the calorie counting does the rest! Simply download a calorie counting app to track the food and drinks you consume throughout the week (the apps you can use will be discussed towards the end of this post). You will see throughout an average week of eating if you undereat and where you can incorporate more healthy meals to reach a healthy, maintenance level of calories to be your healthiest and most productive.
This is just one of the many benefits of calorie counting.
2. Helps Tracks a Calorie Defict when Loosing Weight
If you are on a weight loss journey to be a healthy weight or shredding for the season try calorie counting. Calorie counting is a must to make sure you are eating the number of calories needed to lose excess weight.
Without a calorie counting tool or method, it can be pretty difficult to make sure you are actually in a calorie deficit.
The calorie counting tools provide a guide to make sure you are not in a dangerous state of undereating or you are not too high in calories to reach your weight loss goals. Diet is so important you want to make sure the work you are putting in with your workouts or training pays off with a healthy diet.
It’s important to note macros are so important when trying to eat healthy so make sure to check yours on your calorie tracker. This helps you understand if you are eating healthy. The amount of fat, sodium, cholesterol, etc. is a huge component to seeing HEALTHY progress.
3. Helps You If You are Trying to Gain Muscle or Weight
Yes, the same benefits apply if you are on a journey to gain weight. Calorie counting can be an amazing tool for gaining weight the healthy way. Whether you are trying to bulk in your weight training or have fallen into a habit of undereating needing to get out, try calorie counting. Again, tracking macros are also important so you can make sure you are eating enough of each component.
If you have been trying to gain weight with no success, try to incorporate calorie counting.
4. Provides a Guideline to Your Nutrionist
What’s great about keeping track of your calories is you can provide your weekly log of food to your nutritionist or health care provider. This can be helpful to gain insight into how to eat more healthily or what changes you could make to be more productive in all areas of life.
Receiving nutritional advice can help identify possible food allergies and/or sensitivities, ways to boost energy, weight loss tips, and more! Of course, they need a guideline such as a food diary of the number of calories and/or macros you are taking in. That’s where the benefits of calorie counting come in.
Now, that I went over the benefits and ways to utilize calorie counting let’s go into the tips to counting calories effectively