How Many Calories Should You Eat

BMI (Body Mass Index)

If your reading this, you’re probably over weight but how over weight are you? A basic and good guide is body mass index.

Underweight: <18.5

Healthy weight 18.5-24.9

Overweight: 25-29.9

Obese: 30-34.9

Obese Class 2: 35-39.9

Obese Class 3: >40


To work this out there is an equation…

-Divide your weight in kilograms (kg) by your height in metres (m)

-Then divide the answer by your height again to get your BMI

For example:

-If you weigh 70kg and you're 1.75m tall, divide 70 by 1.75 – the answer is 40.

-Then divide 40 by 1.75 and your BMI is 22.9.

Your BMI: ….....….....kg ÷ ….....….....m = ….....…..... ÷ ….....….....m = ….....….....BMI

This will show you how far you need to go until you’re a healthy weight. The higher you are above 25 the more health conditions you are putting yourself at risk of.

Losing weight is a numbers game that isn’t fun. To lose 1Ib of bodyfat you need to burn 3500kcals. This equates to a deficit of 500kcal per day but how do you know how many calories that is a day for you?

BMR (Basal Metabolic Rate)

To find this out first you need to work out your basal metabolic rate (BMR) and sorry this requires more maths. BMR is how many calories your body burns to stay the same weight if you did absolutely nothing all day. This simple equation is shown below.

Men

10-17 years: BMR = 17.7 x weight(kg) + 657. Deviation = 105

18-29 years: BMR = 15.1 x weight(kg) + 692. Deviation = 156

30-59 years: BMR = 11.5 x weight(kg) + 873. Deviation = 167

Women

10-17 years: BMR = 13.4 x weight(kg) + 692. Deviation = 112

18-29 years: BMR = 14.8 x weight(kg) + 487. Deviation = 120

30-59 years: BMR = 8.3 x weight(kg) + 846. Deviation = 112


Your BMR: ….....…..... x ….....….....kg = ……………. + ….....…..... = ….....….....Kcal per day.

DER (Daily Energy Requirement)

Now the bit that’s important to find out how many calories you burn in a day. This is called daily energy requirement (DER). To find this out we simply multiply your BMR by an amount that correlates with your activity level.

BMR x 1.4 for inactive men and women

BMR x 1.6 for moderately active (2-3 hours a week) women or 1.7 for men

BMR x 1.8 for very active (4-7 hours week) women or 1.9 for men

Your DER: …....…...... x …....…...... = …...….......Kcal per day.

Now you know how many calories a day you burn and you also know that to lose 1Ib (454g) of fat a week, you need to be in a deficit of 500 kcal per day.

Example:

If my BMR is 1620 kcal @65kg and I’m very active so my DER is 1620 x 1.9 = 3078 kcal

I need to eat around 2500 kcal to lose a pound of fat a week.

Your DER …....…...... – 500 = …....…......

Now you know how many calories you need to eat, we can move onto food choices.

NEXT WEEK - Food Choices