How Many Calories Should a Human Eat a Day to Stay Alive?

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The number of calories a you need to stay alive depends on your age, height, weight and activity level. It is easy to calculate using the basal metabolic rate formula and the Harris Benedict equation.

Staying Alive

Everything you do uses calories, even breathing and digesting your food. The way to figure out how many calories you need to stay alive depends on your activity level. If you are very active you will need far more calories than if you are sedentary. The calories your body burns just to keep you alive is called your basal metabolic rate. This resting metabolic rate is based on how many calories you would burn if you just lay on the floor all day.

BMR

To figure BMR for women, the formula is: 655 + (4.35 x weight in pounds) + (4.7 x height in inches) -4.7 x age in years). An 18-year-old woman who is 5 feet tall and weighs 110 lbs. would have a BMR of 1,330.9. The formula for men is: 66 + (6.23 x weight in pounds) + 12.7 x height in inches) - (6.8 x age in years). A 65 year-old man who is 6 feet, 2 inches, weighing 200 lbs. would have a BMR of 1,809.8.

Harris-Benedict Equation

The Harris Benedict Equation assumes you will have more activity than just lying around all day. To figure calories needed if you are sedentary, multiply BMR by 1.2; if you are lightly active, multiply by 1.375; moderately active, multiply by 1.55; very active, 1.725; if you are extremely active, multiply by 1.9.

Calories To Eat

The number of calories a you need to stay alive depends on your age, height, weight and activity level. It is easy to calculate using the basal metabolic rate formula and the Harris Benedict equation.

Staying Alive

Everything you do uses calories, even breathing and digesting your food. The way to figure out how many calories you need to stay alive depends on your activity level. If you are very active you will need far more calories than if you are sedentary. The calories your body burns just to keep you alive is called your basal metabolic rate. This resting metabolic rate is based on how many calories you would burn if you just lay on the floor all day.

BMR

To figure BMR for women, the formula is: 655 + (4.35 x weight in pounds) + (4.7 x height in inches) -4.7 x age in years). An 18-year-old woman who is 5 feet tall and weighs 110 lbs. would have a BMR of 1,330.9. The formula for men is: 66 + (6.23 x weight in pounds) + 12.7 x height in inches) - (6.8 x age in years). A 65 year-old man who is 6 feet, 2 inches, weighing 200 lbs. would have a BMR of 1,809.8.

Harris-Benedict Equation

The Harris Benedict Equation assumes you will have more activity than just lying around all day. To figure calories needed if you are sedentary, multiply BMR by 1.2; if you are lightly active, multiply by 1.375; moderately active, multiply by 1.55; very active, 1.725; if you are extremely active, multiply by 1.9.

calculate your daily calorie maintenance level

How Many Calories Are Needed To Maintain My Current Weight?

In the previous step, I showed you a couple of ways to calculate your daily calorie maintenance level

Now, if your goal was to lose weight or gain weight, this would be the step when you adjust that calorie intake to suit one of those goals.

However, since you're only interested in how many calories are needed to maintain your current weight, you get to skip right past that step.

Why? Because your calorie maintenance level already is how many calories are needed for you to maintain your current weight. You already did 99% of the work in that last step when you calculated what yours is.

(If you skipped the previous step, now is the time to go back and do it.)

All that's left to do now is make sure the amount of calories you calculated truly is 100% accurate for you and truly is how many calories you need to eat per day to maintain your current weight. Let me explain…

The Problem With Calorie Calculators & Estimates

Even though I just showed you some of the most popular methods of estimating your daily calorie maintenance level, there is one tiny problem.

The word “estimating.”

You see, any online calculator or similar method of calculating calories will only be giving you an estimate.

These methods might be quite accurate for most people, but in the end, they are always just guesses, not guarantees. There are just too many individual factors at play that “calorie calculators” are unable to take into account.

Which means… those estimates are sometimes wrong. Luckily however, we have a way to double check it.

The human body actually has its own built in method of figuring out EXACTLY what your daily calorie maintenance level is and guarantees 100% accuracy every single time.

How To Figure Out Exactly How Many Calories Are Needed To Maintain

To figure out exactly how many calories are needed to maintain your current weight, all it takes is a very simple 4 step experiment:

1. Consistently eat the same number of calories each day for a few weeks, and keep your activity level fairly consistent as well.
2. Weigh yourself about once per week (first thing in the morning on an empty stomach).
3. Monitor what happens.
4. Adjust accordingly if needed.

So, take the calorie maintenance level estimate you calculated in the previous step and use that as your calorie starting point. Now, just start eating that amount each day for the next few weeks.

For the sake of an example , let's pretend an example person estimated that their daily maintenance level is 2500 calories. Starting tomorrow, this example person would eat about 2500 calories each day. It doesn't have to be absolutely exact, but try to get within 100 or so calories of your estimated amount.

Then, just eat this number of calories each day for the next 2-3 weeks.

Be sure to weigh yourself first thing in the morning on empty stomach at the end of each week and write your weight down somewhere.

Then, just watch and see what happens, and adjust if needed. Meaning…

• Is your weight staying about the same ? If so, congrats… you've successfully found exactly how many calories are needed to maintain your current weight. Keep eating this amount from now on.
• Is your weight increasing ? If so, you are above your maintenance level (a caloric surplus). Slightlydecrease your daily calorie intake by about 250 calories, wait a few weeks, and see what happens then. For example , our same example person would now start eating 2250 calories per day.
• Is your weight decreasing ? If so, you are below your maintenance level (a caloric deficit). Slightlyincrease your daily calorie intake by about 250 calories, wait a few weeks, and see what happens then. For example , our same example person would now start eating 2750 calories per day.

So basically, eat about the same number of calories per day and monitor what your weight does. If it stays the same, perfect! If it doesn't, then just adjust your daily calorie intake up or down in small 250 calorie increments until it does.

When you reach the point where you are maintaining your weight from week to week, you're done. That’show many calories you need to eat per day to maintain your current weight.

Taaadaaa! Make sure you write it down.

What's Next?

Now that you've found exactly how many calories are needed per day to reach your specific goal (maintaining your current weight), it's time to figure out exactly where those calories will come from.

First up, let's look at protein and find out what your ideal daily protein intake is.

Lose Fat

If you're here, it means you want to lose weight (more specifically, lose fat ), and you're ready to figure out how many calories you should eat per day to make that happen as effectively as possible. Awesome.

Before we get to that, here's a quick recap of what you've done so far:

• You learned that in order to lose weight or lose fat, a caloric deficit is the #1 requirement.
• You learned that a “caloric deficit” means eating fewer calories than your body needs, which means you need to be below your calorie maintenance level. (This forces your body to burn your own stored body fat for energy instead, which is a requirement for fat loss.)
• You estimated what your daily calorie maintenance level is. (If you skipped that step, now is the time to go back and do it.)

Now, with your estimated calorie maintenance level in mind, the next obvious step in figuring out how many calories you should eat per day to lose weight is figuring out what size the caloric deficit should be.

Meaning, how many calories below your maintenance level should you be each day to lose weight?

Let's answer that…

Creating Your Ideal Caloric Deficit

Even though your #1 goal is to lose fat, there are actually 3 goals to keep in mind when creating a caloric deficit:

1. Maximizing fat loss.
2. Minimizing muscle loss.
3. Doing it all in a way that is as doable and sustainable for you as possible.

Knowing this, there are typically 3 different categories of “sizes” that the deficit can be: small ,moderate , or large . Each has its own PROS and CONS, but here's what matters most.

If your deficit is too small, it means you will lose weight/lose fat at the slowest possible rate. If your deficit is too large, it will be extremely hard to sustain (because you'll be the most hungry and annoyed), workout performance will suffer, and the potential for muscle loss will be at its highest.

I actually explain all of this in more detail right here: Caloric Deficit

But for all of these reasons and more, I (and most experts) most often feel that a moderate caloric deficit is the perfect choice for the majority of the population. It's just what works best in most cases.

Now, what exactly is a “moderate” deficit, you ask? Here's what I recommend…

How Many Calories Should I Eat Per Day To Lose Weight?

The Ideal Daily Caloric Deficit : 20% below maintenance level per day.

What this means is, whatever your daily calorie maintenance level is, you should be about 20% below it each day. Here's an example…

• Let's say some person (male or female) had a daily calorie maintenance level of 2500 calories. They'd first figure out that 20% of 2500 is 500 (2500 x 0.20 = 500). This means they should create a caloric deficit of 500 calories each day. In this example, that would mean eating 2000 calories per day.

So, take the estimated calorie maintenance level you got in the previous step and create your 20% deficit.Did you do it? Good. That's how many calories you should eat per day to lose weight. Taaadaaa!

Make sure you write it down.

Because this deficit (20% below maintenance) is neither too big nor too small, it will allow you to maximize fat loss, minimize muscle loss, and do it all in a way that is easy for you to manage and sustain both physically and mentally.

That's pretty much as good as it gets, and that's precisely why this is the most often recommended caloric deficit for the majority of the population looking to lose weight/lose fat.

Of course, one of the main reasons this deficit is so ideal is that it will cause you to lose weight at theideal rate of weight loss .

What ideal rate of weight loss, you ask?

This one…

The Ideal Rate of Weight Loss

You see, if you have properly created the ideal caloric deficit and are therefore eating your ideal amount of calories per day, it will cause you to lose weight at the ideal rate.

Here now is what that rate should be for the majority of the population:

The Ideal Rate Of Weight Loss : between 0.5 – 2 pounds lost per week.

That range is a bit broad, but that's because the ideal rate of weight loss will (and should) vary based on how much fat a person has to lose.

Confused? Here's a chart that narrows that range down a bit…

The Ideal Rate Of Weight Loss Based On How Much Fat You Need To Lose

Amount Of Fat To Lose	Ideal Rate Of Weight Loss
Above Average	2lbs (or more) per week.
Average	1-2lbs per week.
Below Average	0.5-1lb per week.

Now let's break that chart down…

• Someone with an above average amount of fat to lose (say 100lbs, for example) can (and probably should) lose it at a rate of 2lbs (or more) per week, at least for a certain amount of time.
• Someone with a more average amount of fat to lose (say 30lbs, for example) should lose it at a rate of 1-2lbs per week.
• Someone with a below average amount of fat to lose (say 10lbs or less, for example) would be best served to lose it at a rate of 0.5-1 pound per week.

It's also possible for a person to be in 2 or 3 of the categories shown on the chart above at different stages of their weight loss.

Meaning, a person might start off with a lot of fat to lose at which point they might lose it at a rate of 2lbs or more per week for a while. They'll then hit a point where that rate slows down a bit to 1-2lbs per week for a while. And then, when they are almost done losing all the fat they needed to lose, it may only happen at a rate of 0.5-1lb per week at that point.

Either way, creating the ideal caloric deficit (20% below maintenance) will always cause weight to be lost at the rate that's most ideal for you.

Sounds good, right? Now let's make sure it all works correctly.

How To Guarantee You're Eating The Right Amount Of Calories Per Day

OK, let's recap real fast. First, you learned what the ideal caloric deficit is. Then, you used that information to adjust your estimated calorie maintenance level and figure out exactly how many calories you should eat per day to lose weight.

After that, you learned what the ideal rate of weight loss is for you and this new ideal calorie intake of yours.

All that's left to do now is make sure everything is 100% accurate and guaranteed to work .

Remember in the previous step when I mentioned that there would be a way to double check your daily calorie intake to make sure it was 100% perfect for your goal of losing weight? Well, here it is.

All you need to do is start eating your new ideal amount of calories each day and then just weigh yourself about once per week (first thing in the morning on an empty stomach) and watch what happens.

Based on what your weight is doing from week to week, here's what you should do:

• Are you losing weight at the ideal rate? If so, congrats! This means your daily calorie intake is indeed perfect. Keep eating this amount of calories each day and enjoy the awesome fat loss results that are guaranteed to follow.
• Are you gaining weight or just maintaining your current weight? If so, your deficit isn't big enough (or it just doesn't exist at all) and therefore needs to be increased. So, just reduce your current daily calorie intake by about 250 calories (so if you were just eating 2500 calories per day, you'd now eat 2250 calories per day) and then monitor what your weight does over the next couple of weeks. Based on what happens, come right back here and follow the appropriate instructions.
• Are you losing weight faster than the ideal rate? If so, and it's been happening for a few weeks consistently, your deficit is likely a little too big and it should probably be decreased. Just add about 250 calories to your current daily calorie intake (so if you were just eating 2500 calories per day, you'd now eat 2750 calories per day) and then monitor what your weight does over the next couple of weeks. Based on what happens, come right back here and follow the appropriate instructions.

Basically, weigh yourself about once per week (always first thing in the morning on an empty stomach) and keep track of it somewhere. If you are losing weight at your ideal rate, you're perfect. If you aren't, then just adjust your calorie intake up or down in small 250 calorie increments until you are. Simple as that.

What if I reach a “plateau” and I stop losing fat?

Oh, and if you ever reach a point where you were losing weight at the ideal rate for a while but then it stops for a couple of weeks in a row, guess what you should do? Yup, just reduce your current daily calorie intake by about 250 calories and see what happens then.

It honestly is that simple.

And with that, the most important part of your diet is all figured out and ready to go. Good job!

What's Next?

Now that you know how many calories you should eat per day to lose weight/lose fat, it's time to figure out where those calories will come from.

First up is protein, which is the second most important part of every fat loss diet. Let's find out why, and how much of it you should eat…

Calories For Men

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Calculcate your BMI, or body mass index, to determine if you need to lose weight. If you weigh 190 lbs. and are shorter than 5 feet 10 inches, you're considered overweight.

Basal Metabolic Rate

Basal metabolic rate, or BMR, is a formula that calculates the number of calories you burn if you stay in bed all day. Use this formula to calculate your BMR if you're a female: ( 4.35 x weight in pounds ) + ( 4.7 x height in inches ) - ( 4.7 x age in years ). If you're a male, use this formula: ( 4.35 x weight in pounds ) + ( 4.7 x height in inches ) - ( 4.7 x age in years ).

Harris Benedict Equation

The Harris Benedict Equation is a formula that calculates your BMR with your activity level. This number will tell you how many calories you can eat to maintain your current weight. Multiply your BMR by 1.2 if you're inactive. If you're moderately active, multiply your BMR by 1.55. If you're active, multiply your BMR by 1.725.

Calorie Information

You need to create a 500- to 1,000-calorie deficit in your diet, or by exercising more, to lose 1 to 2 lbs. a week. The National Institutes of Health suggests that you keep your weekly weight loss total to no more than 2 lbs.

Eat Calories To Lose Weight

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The National Institutes of Health reports that the best way to lose weight is by taking in fewer calories than you use. That does not mean you shouldn't watch what you eat. In fact, by not limiting your calorie intake to a number formulated to suit your age, height, activity level and gender, you could sabotage your chances of getting to an appropriate weight.

Basal Metabolic Rate

The Basal Metabolic Rate, or BMR, which is sometimes interchangeable with your resting metabolic rate, is a calculation of the number of calories you burn when using the least amount of energy, such as when you're asleep. By determining how many calories your body uses when doing nothing, you can establish how many calories you need to take in each day to maintain -- not lose -- your current weight.

Calculating Your BMR

To calculate your BMR use this formula, which is specifically tailored for women:
655 + ( 4.35 x weight in pounds ) + ( 4.7 x height in inches ) - ( 4.7 x age in years ) = BMR

Daily Calorie Needs

Your BMR is just the start of finding out how many calories you can eat daily and lose weight. Because it's likely that you do not do nothing all day, the Harris Benedict Equation will determine how many calories you need based on your BMR and your activity level. So, again, the number you get from this formula will indicate how many calories you need to take in just to maintain your current weight.

Multiply your BMR by X, with X representing your activity level. X equals:
1.2 if you get little or no exercise daily.
1.375 if you get light exercise, about one to three days a week.
1.55 if you are moderately active, exercising about three to five days a week.
1.725 if you exercise six or seven day a week.
1.9 if you have a very physical job and exercise hard.

Losing Weight

The American Academy of Family Physicians, AAFP, explains that to lose weight, you need to reduce your calorie intake by 500 calories a day to lose 1 pound a week. Once you've established your daily calorie needs using the Harris Benedict Equation, simply reduce your calorie intake by 500. You can also split your calorie deficit between taking in fewer calories and burning calories through exercise. The AAFP goes on to say that reducing or burning up to 1,000 calories a day should be your limit. Losing more than 2 pounds a week could mean that you're burning lean muscle mass or water weight instead of excess fat.

Warnings

The NIH reports that it's unhealthy to deprive yourself of food. You should not consume fewer than 1,200 calories unless you are on a special medically supervised diet. A very low calorie diet, which is the intake of between 500 to 800 calories a day, is only for people whose weight has put them at immediate risk for serious medical complications.

Your Apple Cider Vinegar Weight Loss Stories

A Healthier Leaner Me I CAN DO THIS with ACV!

by Rose
(Ontario, Canada)

I'm a tall woman that stepped on the scale 11 days ago and saw 254 lbs. so I've vowed to make a lifestyle change.

I don't have any special events coming up, I am not doing this because it's a new year or for anyone but myself...I've had enough of sitting down and feeling uncomfortable because my jeans were digging into my belly.

I've had enough of looking at this double chin every time I looked in the mirror.

I've had enough of these love handles and rolls of fat on my back.

Now on to the ACV...

I have used ACV quite often over the years for my hair and for my skin (toners and facial masks). I have used it for drinks as well but I was never consistent.

Although it's only been 10 days I am LOVING the changes so far.

First this is what I do...

In the morning I fill up a 32 oz. plastic cup that has a cover (the kind you get at sporting events) with room temp distilled water. I've been putting 2 tablespoons of Braggs ACV in it along with a half teaspoon of Manuka honey. I drink half the water.

Wait about 15 mins. then have breakfast (usually just a healthy cereal with rice milk and a piece a fruit or oatmeal with raisins.) I finish the rest of the water within the hour.

About an hour and a half later I workout at home for about 20 - 30 mins. doing a mixture of DVD videos and getting on my mini stair stepper. When I'm done working out I'll drink a glass of water eat a Nutragrain type bar.

Around noon I prepare another ACV/water cocktail and drink half of it. 15 mins. later I'll have lunch (something like a turkey salad with veggies and fruit). An hour later I'll do Pilates for about 15 - 20 mins.

For a mid-afternoon snack I'll have something like regular water, a homemade fruit smoothie, tea or chocolate milk (the powered kind but I use water) with unsalted cashews or crackers.

Fifteen minutes before dinner I'll finish the remaining 16 oz. of the ACV cocktail from earlier.

Doing this for 10 days has got me down to 244 lbs!!! That's 10 lbs. in 10 days folks!!! In the first 5 days I lost 7 lbs.! People have already noticed my weight loss too which inspires me further.

Although I have been going to the restroom like crazy and waking up in the middle of the night to go (both ways---sorry!) my mind is clearer, I have much more energy, all cravings are gone (I HAD a sweet tooth), my face and stomach are getting slimmer and my clothes are fitting much, much better! This is just a start though and I'm not stopping.

So along with drinking ACV (4 tablespoons per day) and drinking approximately 80 oz. of water everyday, what's been helping me is changing my mindset about food (eating to live not living to eat), getting active along with watching the calories. I am not starving myself or doing strenuous exercise.

I truly hope my words and/or routine helps someone out there.

Good luck!