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I’d like to lose the 20lbs that stand between me and a size 12, or  even the 50lbs that stand between me and a size “Wow!”.  I know that to do so I need to make calories in less than calories out. But how many calories should I shoot for in general?

I’ve used a number of calculators, with so vastly different results.

Here’s two examples:

The American Cancer Society says I need 2318.

The Mayo Clinic says I need 1550.

What gives? Where can I get a reliable number?

Thanks,
Naomi

Ok.  Wow.  You guys have really decided to stop throwing softballs at us when it comes to these questions, haven’t you?  Next time why not ask us how to perform open heart surgery or something?  Sheesh.

Seriously, though – The reason this is a difficult question is because the first (and most honest) response is “it depends.”  It depends on a lot of things.  It depends on how old you are, how tall you are, how much you weigh currently, how active you are, what your sex is, and what type of calories you’re putting in to your body (a 1200 calorie a day diet consisting of nothing but Snickers bars isn’t very likely to warrant positive results).  With all of those factors in place it is no wonder that you’re having a hard time finding a solid answer to your question.

If you’re looking for a straight-up calorie goal I’ve found a very useful suite of online tools at BMI-Calculator.net.  This site helps you determine your Basal Metabolic Rate (BMR – the number of calories you would burn in a day if you did nothing but lay in bed) and then use that number along with an assessment of your daily activity to determine the number of calories you would need to consume to maintain your current weight.  You can then use that number to determine how many calories you should trim from that number in order to achieve a healthy level of weight loss.

I’ll use myself as an example to show you how this works.  I am a 36 years old male, I am 6’2″ tall, and I currently weigh 245.8 pounds.  According to the BMR Calculator I burn at least 2348 calories per day.  I would consider myself moderately active (moderate exercise/sports 3-5 days a week) so I multiply that number by 1.55 to arrive at a daily calorie goal of 3639 to maintain my current weight.   I can then use that number to determine a healthy range of calories I need to consume in order to lose weight.  I can either just drop 500 to 1000 calories from my maintenance target (giving myself a goal between 2639 and 3139), or I can reduce that numer by 15% for a target of 3093.

It is important to note that, according to the American College of Sports Medicine, you should never drop below 1200 calories a day if you’re a woman or 1800 calories a day if you’re a man.  If you need to lose weight and your target numbers drop below those numbers you should eat your maintenance calories and burn off the excess by increasing your exercise.

The BMR formula is, essentially, what Weight Watchers® is doing with their current POINTS system, as you need to factor in your age, weight, sex, and activity level in order to determine your daily POINTS target.  The main difference is that Weight Watchers also factors in the fat and fiber of the food you eat, so it’s not a straight calorie for calorie exchange.  In my opinion the Weight Watchers method is considerably simpler, and that’s one of the reasons why I love it and have been on program for over 8 years.   If you are the type who wants an actual calorie target the site I linked to above should work for you.

Please remember that whatever method you use to determine your daily food intake if you’re losing more than 1 to 2 pounds a week after the first few weeks you are not eating enough. Healthy weight loss should be gradual, and if you’re losing more than a few pounds a week you are likely burning off more muscle than fat.  As my Weight Watchers leader says, you didn’t put all the weight on overnight so you can’t expect to take it off overnight either.

Hope this helps!

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