Calculating Carb Intake For Weight Loss On Keto

The keto diet is a low-carb, high-fat, and moderate-protein diet. It involves limiting your carbohydrate intake so that your body uses fat as its primary energy source. The keto calculator helps you determine your optimal macronutrient intake for weight loss, weight gain, or weight maintenance. It takes into account factors such as your gender, age, height, weight, body fat percentage, and activity level. By entering these details, the keto calculator can estimate your basal metabolic rate (BMR) and total daily energy expenditure (TDEE). It also allows you to set a calorie deficit or surplus to achieve your weight goals. The keto calculator then provides you with personalised macro targets, including the number of grams of net carbs, protein, and fat you should consume daily.

How to calculate your basal metabolic rate (BMR)

To lose weight on a keto diet, it is recommended to consume between 20 to 50 grams of carbohydrates per day. However, the number of carbs you should eat depends on your age, weight, physical activity, and medical history.

Now, to answer your question about calculating your basal metabolic rate (BMR). Your BMR is the number of calories your body uses to stay alive and perform basic, life-sustaining functions. This includes the energy required for:

• Heart rate and blood flow
• Metabolism (digestion and nutrient absorption)
• Cell function, growth, and repair

Your BMR does not include the additional calories needed for daily activities such as walking, moving, and exercising.

There are three main ways to calculate your BMR: direct calorimetry, indirect calorimetry, and mathematical equations. Direct calorimetry is the most accurate method but is usually only available in research settings. Indirect calorimetry uses an in-office device to measure the exchange of oxygen and carbon dioxide in your body.

If you don't have access to these methods, you can use mathematical equations like the Mifflin-St. Jeor equation to calculate your BMR. Here are the equations:

For men: BMR = 10 × weight (in kilograms) + 6.25 × height (in centimeters) – 5 × age (in years) + 5

For women: BMR = 10 × weight (in kilograms) + 6.25 × height (in centimeters) – 5 × age (in years) – 161

For example, let's calculate the BMR for a 35-year-old male who weighs 90 kilograms and is 183 centimeters tall. Using the equation:

BMR = 10 x 90kg + 6.25 x 183cm - 5 x 35 years + 5

BMR = 1882 calories per day

So, at rest, this person will burn around 1,882 calories in a day.

Remember, your BMR is just the number of calories your body needs at rest. If you want to calculate your total daily calorie expenditure, you need to multiply your BMR by an activity factor, which depends on your lifestyle and exercise habits.

How to calculate your total daily energy expenditure (TDEE)

To calculate your Total Daily Energy Expenditure (TDEE), you must first determine your Basal Metabolic Rate (BMR). This is the minimum number of calories your body needs to function while at rest. Your BMR is calculated based on your physical characteristics, such as age, gender, height, and weight.

There are several formulas for estimating BMR, including the Mifflin-St Jeor Equation, the Harris-Benedict Equation, and the Katch-McArdle Formula. The Mifflin-St Jeor Equation is as follows:

• Men: calories/day = 10 x weight (kg) + 6.25 x height (cm) - 5 x age (y) + 5
• Women: calories/day = 10 x weight (kg) + 6.25 x height (cm) - 5 x age (y) - 161

Once you have calculated your BMR, you then need to multiply it by an activity multiplier, which takes into account how active your lifestyle is. The activity multiplier will depend on the amount of deliberate exercise you do, as well as other activities you do as part of your job or daily routine.

For example, if you have a sedentary lifestyle with limited to no exercise, the activity multiplier is 1.2. If you are lightly active, doing light exercise one to three times per week, the activity multiplier is 1.375. If you are very active and do hard exercise six to seven times per week, the activity multiplier is 1.725.

So, to calculate your TDEE, you take your BMR and multiply it by the relevant activity multiplier. This will give you an estimation of the total number of calories you burn per day when exercise is taken into account.

How to determine your calorie intake goal

To determine your calorie intake goal, you must first calculate your Basal Metabolic Rate (BMR), which is the minimum number of calories your body needs to function while at rest. Your BMR is calculated using the Mifflin-St Jeor Formula, which takes into account your gender, age, height, and weight.

For men, the formula is: calories/day = 10 x weight (kg) + 6.25 x height (cm) – 5 x age (y) + 5

For women, the formula is: calories/day = 10 x weight (kg) + 6.25 x height (cm) – 5 x age (y) – 161

Once you have your BMR, you can calculate your Total Daily Energy Expenditure (TDEE) by multiplying your BMR with an activity factor, which depends on your activity level.

• Sedentary (limited to no exercise with a desk job): BMR x 1.2
• Lightly active (light exercise one to three times per week): BMR x 1.375
• Moderately active (moderate exercise three to five times per week): BMR x 1.55
• Very active (hard exercise six to seven times per week): BMR x 1.725
• Extra active (arduous exercise daily and a physical job): BMR x 1.9

Your TDEE will give you an estimate of the total number of calories you burn per day, which you can then adjust based on your goal. If you want to maintain your weight, you should consume the same number of calories as your TDEE. If you want to lose weight, you should consume less than your TDEE, and if you want to gain weight, you should consume more.

For example, if your TDEE is 2,000 calories and you want to lose weight, you could aim for a calorie deficit of 10%, which would mean consuming 1,800 calories per day.

It's important to note that these calculations are just estimates, and individual results may vary. It's always a good idea to consult with a healthcare professional or dietician to determine the best calorie intake goal for your specific needs and health parameters.

How to calculate your body fat percentage

To calculate your body fat percentage, you can use a body fat calculator, which is the easiest method as it requires no special tools or lengthy appointments with a specialist. You will need a basic tape measure and about five minutes to gather the data you need for an instant body fat measurement.

The measurements that need to be taken are slightly different for men and women. Men only need to measure waist circumference, while women also need to measure their hips, wrist, and forearm.

For men:

• Current weight
• Waist circumference: Measure the largest part of your belly, usually at the level of your belly button. Ensure the tape measure stays level with the floor. Don't hold your breath or suck in to get the measurement.
• Neck circumference: Measure your neck starting below the larynx, with the tape sloping downward to the front. Avoid flaring your neck outwards.

For women:

• Current weight
• Waist circumference: Measure the largest part of your belly, usually at the level of your belly button. Ensure the tape measure stays level with the floor. Don't hold your breath or suck in to get the measurement.
• Wrist circumference: Measure the smallest part of your wrist. You may need a partner to help with this measurement.
• Hip circumference: Measure the largest part of your hips, usually at the posterior extension of the buttocks.
• Forearm circumference: Measure the widest part of your arm below your elbow. It will be easiest to have a partner get this measurement. Keep your arm relaxed and let it hang alongside your body.

Once you have gathered your data, input it into a body fat calculator to get your body fat percentage.

There are also other ways to measure body fat percentage, such as skinfold calipers, bioelectrical impedance, whole-body scanning, and hydrostatic weighing. These methods may be more accurate but are often more invasive, costly, or require specialist equipment or settings.

How to calculate net carbs

To calculate net carbs, you need to subtract the fibre from the total number of carbs. This is because fibre is a complex carb that the body cannot fully digest.

The formula for calculating net carbs is: Total carbs – fibre – certain sugar alcohols = net carbs.

For example, if a medium avocado contains 17.1 grams of total carbs, 13.5 grams of which is fibre, then the net carbs would be 3.6 grams (17.1 grams total carbs – 13.5 grams fibre = 3.6 grams net carbs).

It is important to note that the term "net carbs" is not recognised by the Food and Drug Administration (FDA), which instead recommends using the total carbohydrates listed on food nutrition labels.

Additionally, when calculating net carbs in processed foods, it is generally recommended to subtract half of the carbs from sugar alcohols. However, if the only sugar alcohol present is erythritol, its entire carb value can be subtracted from the total carbs.

Frequently asked questions