How Many Calories Do I Need To Lose Weight?
How many calories do I need to lose weight? You probably do need to reduce your calorie intake, but also not by too much as consuming fewer calories than what your body needs in an attempt to lose weight can eventually lead to no weight loss at all. So just how many calories should you consume to lose weight?
You want to eat enough calories to provide your body with everything it needs to function, but not much more than this, it’ll lead to weight gain. Eating well under your calorie intake can eventually slow down your metabolic rate (‘starvation mode’) where you’ll struggle to lose any weight (meaning your body is less effective in burning fat).
How many calories do I need to lose weight?
We all have different energy requirements. Your energy needs vary depending on your activity levels, body composition, desired body composition, state of health, age, weight, height, gender etc.
It’s recommend that females consume the following range of calories a day:
For example, if you’re 32 years old, sit at a desk most days, travel to and from work sitting down, but do light exercise some days, you’re a mostly sedentary person.
You don’t burn much energy, so an ideal calorie intake for the day to avoid weight gain, would be around 1,738 cal per day (or 7,300 kJ).
If you’re 32 years old and a highly active professional athlete your energy requirements will be more than the above example. A more ideal calorie intake would be at the upper limit of around 2, 976 cal per day (or 12,500 kJ).
However! These recommendations from health authorities were published many years ago. Since then, our lifestyles have changed dramatically. We’re a lot more sedentary than when these recommendations were published. Therefore, I would personally consume closer (or maybe even slightly under) to the lower recommended amount on my sedentary days. For me, when I’m sitting/driving for most of the day ideally I would consume around 7,000kJ. If I do exercise that day I might allow myself around 8,000kJ. If I wanted to lose weight, I would probably drop my kJ down to around 7,000-8,000kJ and exercise as well (but not much less than this, I am quite muscly and I want to maintain that).
So how many calories should you have if you want to lose weight?
It’s not something I can generally say. Everyone is different. It depends on so many factors, especially your body composition. If you have a decent amount of muscle, or want to build muscle, you’ll need more calories than someone who doesn’t have much muscle or doesn’t have the desire to build any more.
Very generally, I would say to not eat less than 6,000kJ per day. Your body needs a certain amount of energy per day to function. The amount of energy your body needs just to function is called your BMR (basal metabolic rate). If you have a fitbit, or something similar, it actually gives you your estimated BMR. You should never really eat fewer calories than your estimated BMR in any situation. And if you’re trying to lose weight, you should try to consume roughly the amount of calories as your BMR (try not to consume too many calories over your BMR).
Eating less than this may see you lose weight initially, but you might struggle to continue to lose weight, or maintain it due to either: a decrease in your BMR (your metabolism slowing down to preserve energy because it doesn’t think its getting enough), a decrease in muscle mass (due to insufficient energy to build/maintain muscle mass) therefore a decrease in your BMR, or just the fact that you can’t maintain it because you’re hungry all the time and it’s too different from what you’re used to eating.
In this case, you need to make small changes gradually in reducing your calorie intake. It’s very difficult to go from say, eating 10,000kJ to dropping down to 7,000kJ… your body will scream out at you with hunger. If you usually eat around 10,000kJ, reduce it to 9,000kJ for one week, then the next week reduce it to 8,000kJ etc. Allow your body time to adapt or else it will fight against you and make your weight loss journey a constant battle. Patience and small gradual changes leads to lifestyle changes, which will lead to weight loss maintenance for life.
What’s the difference between Cals and kJs?
Calories (Cal) and kilojoules (kJ) are used to measure energy contents of foods and beverages, they are the same thing, just different measures. One calorie is equivalent to approximately 4.18 kilojoules.
For example, if the tub of yoghurt you are eating contains 200 calories, it is equivalent to 836 kilojoules. A 50g chocolate bar has 267 calories which is equivalent to 1,116 kilojoules.
What are Cals and kJs used for?
Cals/kJs (energy) gives our bodies the fuel to be active (exercise, movement) and to stay alive (keep our body functioning, internal organs working).
*During pregnancy, lactation and under certain circumstances this value can change. This value is based on Australian recommendations found here.