Quick math lesson! A pound of stored body fat is equal to about 3,500 calories. One way or another, to lose one pound, you’ll need to create a 3,500 calorie deficit. The million dollar question of course, is how to do this. Not to mention, how to create 3,500 calorie deficits for all the other pounds you also want to lose. Take me for example. When I began my weight loss journey I weighed 325 pounds and my initial goal was to get below 200. 125 pounds multiplied by 3,500 calories means I needed to create a 437,500 calorie deficit to reach my goal. When you add to that the fact that I decided to make 185 pounds by final goal then I had to be in the neighborhood of a half a million calorie deficit.

Half a million calories. That is more than enough to make anyone give up before they start. I found that I needed a way to make the numbers a little more digestible (pun possibly intended.) It didn’t take too much time with a calculator to realize that 100 calories a day times 365 days was 36,500 calories per year. And 36,500 divided by 3,500 was a little over 10 pounds. So with some creative rounding I created what I called the 100 calories rule.

### Keep it simple

The basic concept is as follows. For every 100 extra calories you burn every day, or for every 100 calories you cut out of your diet every day, you will “lose” 10 pounds per year. Why is lose in quotation marks? Let’s say you are currently gaining weight at a rate that would normally see the number on the scale increase by 15 pounds this year. If you use the 100 calories rule every day for a year then you will still gain 5 pounds. So in effect, if you cut 100 calories from your daily food intake you will weigh 10 pounds less than you would have, if you had continued to eat and exercise normally.

Seems confusing right? It’s really not, but it’s easier to understand if your weight is stable. Let’s say you’ve weighed 250 pounds for a few years and you’ve decided now is the time to lose some of the extra weight. If you do nothing else besides burn 100 extra calories every day for the next 365 days, you will weigh 240 pounds at the end.

### Burn a Few Extra Calories

There are two ways to create a 100 calorie deficit. One is to consume fewer calories through the food and drink you take in, and the other is to burn more calories through physical activity. Let’s start by looking at what could burn more calories and I’ll again use myself as an example. If I’m walking on level ground at a fast pace (heart rate averaging 120 beats per minute) I burn around 10 calories per minute. Meaning that in only 10 minutes per day, I have my 100 calorie deficit. That was easy! And this is me AFTER losing over 140 pounds! At the beginning of the journey I’d have been burning even more (lower cardio fitness level, higher body mass, yadda yadda yadda.) So it’s entirely possible for someone just starting out to burn even more calories in the same amount of time.

What else burns 100 calories? This isn’t a test. The important thing is to find an activity that you can do every day that will increase your heart rate, and burn more calories. As we just showed, it doesn’t take much. I’m willing to bet if you ask most people “is walking for 10 minutes worth weighing 10 pounds less” they would say absolutely!

The important factor is your heart rate. The higher your heart rate, the less time it will take to burn calories. If you enjoy running (does anyone enjoy running?) then you will be able to burn those calories faster. If you are like me (and all other sane people) then running isn’t an option. I choose walking because it’s easy, free, and allows me time to catch up on podcasts. Linked here is a handy calculator which can help you determine how many calories you are burning.

### Eat a Few Less Calories

What about the other route to 100 calories? Consuming fewer calories. This one can be a little trickier to track, especially if you don’t have a consistent eating pattern. I walk for 10 minutes when I otherwise would have been sitting around, I’ve burned an extra 100 calories. Simple! But how do I track NOT eating calories? The easiest way for me when I first started was to look at things I did every day.

Coffee anyone? I was drinking on average 3 cups of coffee per day with cream (I had always used zero calorie sweetener so this wasn’t an issue.) There are about 40 calories in one ounce of coffee creamer. Multiply that by 3 and we have 120 calories per day or 12.5 pounds per year. I was consuming over 12 pounds of body fat per year just in coffee creamer! That was an easy thing to fix. (That is a lie, I missed having cream in my coffee for a while but eventually got used to it and never looked back.)

So take a look at your routine and see if there are easy ways to cut out 100 calories. Liquids are always an easy target. Most soda is around 150 calories per 12 ounce serving. In “100 calorie rule” speak, that means if you drink one can of soda per day, you are consuming almost 16 pounds of body fat per year. Regular water is starting to sound pretty good right now isn’t it?

Food can be more difficult but simply by making small changes (light dressing instead of regular, cooking spray instead of butter) you can very easily carve 100 calories off of your daily diet and hopefully not even notice the change.

### Rinse and Repeat

So you’re asking yourself. “Wait a minute, can I use the 100 calorie rule a bunch of times per day?!” Of course!! (Ok, you really didn’t need me to tell you that.) “So if I walk for 20 minutes AND I cut out the coffee creamer, will I lose over 30 pounds this year?!?!” Yes. You will. I do my best to walk for 30 minutes on my lunch break every day. Sometimes it’s outside on a sidewalk, on a bike path, or in a parking lot. Sometimes it’s even doing laps around a conference room. 30 minutes a day times 5 days a week times 50 weeks a year (I do take a vacation now and then) and I burn over 21 pounds per year just while on lunch.

The 100 calorie rule is a way I found to keep myself motivated and to make the seemingly monumental task of losing a lot of weight a little bit easier to take on.

And remember, if I can do it…..