How many calories do you need each day to both live a healthy life and meet your weight goals?

The number of calories you can eat determines your portion sizes and portion sizes determine your weight. That’s why you need to figure out how many calories you should eat each day.

Let’s say you are sitting down to breakfast. How much can you have? Then it’s lunch time. How much can you have? You feel like an afternoon snack. How much can you have? It’s dinner time. How much can you have? Hey, dessert looks really good. How much can you have? You would like another glass of wine. Can you?

To answer all these “how much” questions, you first need to know how many calories you can eat each day. Eat more calories than you should and you’ll gain weight.

The formula—I know, I don’t like formulas either—we’ll use to calculate how many calories you should eat each day is given by:

calorie budget = calories for living - calorie deficit from eating less

The calorie deficit from eating less is the number you decided on in the How Much Do You Want to Lose in a Spin? strategy. In that strategy you determined your daily calorie deficit target. The calorie deficit had two parts: the calorie deficit from eating less and the calorie deficit from exercising more. When calculating your calorie budget, we only want to use the calorie deficit from eating less.

Calculate Your Calories for Living

What I call calories for living is usually called your maintenance calorie level: how many calories you need to breathe, heal, think, digest food, and everything else your body does to keep you alive. You need to know this number before you can calculate your daily calorie budget. It doesn’t include calories supporting any exercise you may perform.

I know this sounds a bit complicated. But you probably have no idea how many calories you should eat each day. I know I certainly never did. The problem is, if you don’t know how many calories you should eat then you don’t know how much food you should eat.

The average maintenance level for women in the United States is 2000 calories per day. For men it is 2500 calories per day. These are only averages. Very active people will need a higher number of calories. Some triathletes need as many as 6000 calories a day to maintain their weight.

Rather than write a long sequence of boring instructions on how to calculate your maintenance calorie level it, please use the calculator tool at http://YourDesignerDiet.com to perform the calculations instead. It’s a very complicated calculation that’s confusing and complex when explained. Using the website is much more practical.

In this book, we’ll use 2000 calories for women and 2500 calories for men in all the examples. If you don’t plan to run the calculation, you can use these numbers too.

Finally: Calculate Your Daily Calorie Budget

Now we have all the information we need to calculate your daily calorie budget. Let’s take a look at the formula again:

calorie budget = calories for living - calorie deficit from eating less

We decided for example purposes to use 2,000 calories as the calories for living and 250 as the calorie deficit from eating less. Plug in your own numbers, of course.

So our daily calorie budget is:

calorie budget = calories for living - calorie deficit from eating less

1750                  = 2000                       -  250

If you eat 1750 calories a day and burn an additional 250 through increased activity, you will have a calorie deficit of 500. So, you should lose one pound a week or over 50 pounds a year.

That’s really a lot of weight loss for what is a pretty doable calorie deficit for many people. Don’t worry if your calorie deficit causes slower weight loss, it just means it will take a little more time, and more time is fine.

The daily calorie budget you have just calculated tells you how much food you can have in a day. We’ll use this information later when determining the portion sizes of foods you can eat.

The American College of Sports Medicine (ACSM) recommends that calorie levels should never drop below 1200 calories per day for women or 1800 calories per day for men. Even these numbers may be too low. If you find yourself targeting a calorie budget in this range, you should rethink your goals.

The Calorie Budget is Not Too High, Others are Too Low

After you calculated your calorie budget, are you thinking that the number of calories you are supposed to eat is too high? Are you thinking you’ll never lose weight if you eat so many calories?

Lots of weight loss programs want you to eat a pitifully small 1200 calories a day. And you may think “I gotta go low to lose weight. I’ll just go for it and get the weight loss over sooner.”

That’s a losing strategy. A 1200 calorie diet is semi-starvation for a lot of people. Keep the men in the Minnesota starvation experiment in mind. They were on a semi-starvation diet. Do you want to end up like them? Please read that threat again. Very few people can stay on a diet with their body constantly driving them to eat because they aren’t eating enough.

Less is not more. You aren’t in a race to see who can lose weight the fastest by starving themselves. You are not just trying to lose weight. People lose weight all the time and gain it right back again. The goal is to stay at your target weight for the rest of your life. You’ll never manage to stay on a starvation diet. It’s too hard and even if it wasn’t, starvation doesn’t work as a weight loss strategy.

Your body can’t tell the difference between a diet and starvation. As soon as you start eating too few calories, your body will go into starvation mode and you’ll stop losing weight. That’s why low calorie diets are a sucker’s game. They don’t work for the same reason your ancestors were able to survive all those generations. Your body is looking out for you.

If you do “go for it” by starting a low calorie diet, you’ll drop a lot of weight fast, you’ll be losing more muscle than fat. And that’s not what you want. Muscle burns calories. Lose 5 pounds of muscle and your daily calorie burn plummets by about 250. Over a year that’s 25 pounds of weight gain. And once you go back to a more normal diet, your weight will bounce right back even higher than it was, because you have less muscle and burn fewer calories.

You have to work with your body. You seduce your body into losing weight. You can’t pound your body into shape with an ultra-low calorie diet.

Adjust Your Calories Down Slowly

If you try the How Many Calories are You Really Eating? strategy, you should get a good idea about how much less (or possibly more) you need to eat to meet your calorie budget.

If your calorie budget is substantially higher or lower than your current calorie intake, then you may need to adjust your calories gradually over a period of a few weeks to allow your metabolism a chance to adjust.

Are You Thinking of Food All the Time?

If you’ve cut back your calories to match your calorie budget and you are starting to think of food all the time, it could be a sign of the starvation response. First, recalculate your calorie budget. Perhaps there was a mistake in the calculations.

Second, try increasing your calorie budget a hundred calories or so and see if the constant hunger thoughts go away. Try this a few times. I won’t say increase your calorie budget until you stop feeling hungry, because for some people it’s possible they may never feel full.

You have to understand that eating too few calories is not the way to lose weight. I know this idea may go against every impulse you have. Your brain may scream that you mustn’t eat. You brain may yell that you are eating too much and your calorie budget is too high. Ignore those thoughts. The only way you can stay on a diet for the rest of your life is to eat enough to keep your body from thinking it is starving.

Do You Have to Count Calories Forever?

No, you don’t need to count exact calorie totals forever because that’s too difficult. You just need to become calorie aware. You can do a good job at maintaining your calorie budget by just knowing about how many calories you have eaten and about how many calories you have left to eat. That’s all the information you need to make better eating decisions.

You Need to Recalculate Your Calorie Deficit

Some estimates show that for every 20 pounds of fat you lose, your daily calorie burn drops by 100 calories. So, as you lose weight or gain muscle, you’ll need to recalculate your calorie requirements.

Many people hit a weight loss plateau because they don’t realize that fat requires calories and once you lose some fat you need fewer calories to live. If you don’t reduce your calorie budget, then you stop losing weight. You hit a plateau. But there are deeper reasons while you’ll need to recalculate your calorie budget.

All the numbers you have calculated are simply estimates. They can all be wrong. All the estimates for the number of calories you are eating will be wrong too. That’s why you need to be patient and figure out what you need to do over time. Using the feedback techniques we’ll cover in the next strategy, you can figure out what adjustments you need to make. Using feedback to adjust the number of calories is important for your success over time. But you have to start somewhere.

If you are sure you are eating to your calorie budget and you are sure you are getting your goal amount of exercise then something must be wrong. Recheck everything. Check your portions. Check the activities you are doing. But in the end, if you aren’t losing the weight you expect, then you have to adjust something. You can either lower your calorie budget, increase your exercise levels, or some combination of both.

What matters is making adjustments to what’s really happening in your life, not what some estimated numbers say should happen.