How many calories should I be eating a day to lose weight?

So many clients come to me asking for advice on how to lose weight. The first thing I usually ask them is What is your diet like? How many calories are you consuming a day? How much exercise do you get? These are all factors you need to consider when embarking on a weight loss journey.

To lose weight you need to be in a calorie deficit, which basically means eating fewer calories than you burn a day. But what is a calorie and how do I figure out how many calories I should be eating per day to achieve my goals?

A calorie is a unit of energy and is defined as the amount of heat energy required to raise the temperature of 1 gram of water to 1 degree Celcius.

You use the calories that you eat and drink for essential functions such as breathing, thinking, digesting as well as day-to-day activities. Any excess calories you eat will be stored as fat, so consistently eating more calories than you burn will eventually lead to weight gain. You may wonder which kinds of foods have the most calories. The answer is it depends on which nutrients they contain.

1 gram of carbohydrates =4 calories, proteins =4, Fats= 9, and alcohol =7. In other words, a gram of protein or carbs will give you fewer than half as many calories as a gram of fat.

Being in a Calorie deficit basically means you consume less energy than you utilize or burn throughout the day. You should aim to be in a 500-calorie deficit a day to lose around 1-1.5 pounds a week. Creating a higher deficit than this can be difficult to sustain and can lead to failure and frustration and can sometimes lead to you putting on more weight than you started with. Therefore it is better to have a smaller deficit to create a sustainable healthy weight loss.

How many calories you need depends on factors like gender, age, weight, and activity level. No matter what goal you have in mind whether it be weight loss, weight maintenance, or weight gain, you first need to know what your maintenance calories are (how many calories you need to eat daily in order to maintain your weight.)

You first need to find out what your Basal Metabolic Rate is. Your BMR is the amount of energy (calories) expended whilst at rest. It represents the minimum amount of calories required to sustain vital bodily functions. This counts for about 60 to 70% of all the calories you need each day. Use this equation below to find out. Or you can use a BMR calculator on the Internet to do the hard work for you ;)


BMR = 88.362 + (13.397 × weight in kg) + (4.799 × height in cm) - (5.677 × age in years)


BMR = 447.593 + (9.247 × weight in kg) + (3.098 × height in cm) - (4.330 × age in years)

You then need to calculate your estimated total daily energy expenditure (TDEE). Which is defined as the amount of energy you use for physical activity. That’s everything from brushing your teeth, to mowing the lawn or going to the gym.

BMR x PAL (Physical Activity Level)= TDEE

Very light x 1.2