Janet Bond Brill - Intermittent Fasting For Dummies

A calorie isn’t something tangible, like something you pick up when you hold a chocolate chip cookie. A calorie is instead simply a measurement also known as a unit of energy. Think of an inch as a measurement of length and a calorie as a measurement of energy.

Science has two forms of calories:

Calorie with a small c as in calorie: The scientific description of a calorie is the amount of heat needed to raise the temperature of one gram of water by one degree Celsius. This calorie isn’t the same one most people think of when discussing food, so I don’t discuss it any further.

Calorie with a big C as in Calorie: In nutritionist language it’s called a kilocalorie or kcal for short. Nutritionists use these terms to refer to calories in food or to calories burned during exercise. The scientific definition of kilocalories is the amount of heat needed to raise the temperature of 1 kilogram of water by 1 degree Celsius. You use this calorie when reading the food labels in the supermarket. Note: Books about weight loss and weight gain refer to this type of calorie.

The energy balance equation illustrates how weight loss and gain relate to calories. In order to maintain your current weight, you need to consume approximately the same number of calories as you burn:

Calories in = Calories out

Conversely, if you want to lose weight, you need to consume fewer calories or burn more calories. For most people, a calorie deficit of 500 calories per day is just enough to promote weight and fat loss and unlikely to significantly affect your muscle mass or energy levels.

In addition to intermittent fasting, you should also increase your physical activity — to widen the calorie deficit. Intermittent fasting creates a calorie deficit through its focus on diet rather than exercise alone, a method that many find easier than attempting to lose weight through just exercise. As a general rule, weight loss is generally 75 percent diet and 25 percent exercise. However, don’t nix the exercise in your intermittent fasting lifestyle because physical activity is also important for promoting better health.

Keep in mind that more muscular bodies need more calories to sustain themselves than less lean bodies. If you wish to gain weight (muscle) and still reap the rewards of intermittent fasting, then calories in should be greater than calories out. You can accomplish this by having a highly nutritious caloric-dense diet combined with a solid strength training program (refer to Chapter 14for more about incorporating exercise into your lifestyle).

Your body uses the calories in the food you eat for energy to live (for life-sustaining bodily processes). If you eat more calories than you need for those bodily processes, then you gain weight and those excess calories are stored as fat. (Where you store that fat is genetically determined.)

Today’s society is one where tasty and inexpensive high calorie food pervades the environment and makes it incredibly easy to eat excess calories. Combine this with a sedentary lifestyle, and it’s no wonder that overweight and obesity are epidemic in the United States. A healthy lifestyle means figuring out how to visually monitor your caloric intake so that it becomes second nature recognizing just “how much is too much.”

You can start today to incorporate these tricks to help you manage both sides of the calorie equation.

Foods that are considered high calorie, or calorically dense, have a large number of calories relative to their serving size. Junk food, such as soda and potato chips, typically has a lot of calories with few nutrients. These foods are also known as empty calorie foods, which means they have little nutritional value (no vitamins, minerals, antioxidants, or fiber) so you basically get calories without much else.

For example, a 12-ounce can of regular soda provides you with 39 grams of added sugar and 140 liquid calories that you can easily swallow in a few minutes. Many typical American foods have a lot of empty calories. Oils, butter, and other fats; fried foods; and sugary sweets are high-calorie foods. Zero in on your diet where those junk foods may be sneaking in.

A relatively simple change you can make is to eliminate liquid sugar calories from your diet, such as regular sodas, fruit juices, flavored milks, and other beverages with added sugar. Live by nutritionists’ favorite tip: Don’t drink your calories.

You can also eat calorically dense food that is very nutritious. For example, peanut butter is a healthy protein choice that also contains a nice amount of good fats and some fiber. Peanut butter is also a good source of magnesium, which is an essential nutrient for people with diabetes. Beware though, two tablespoons pack a huge calorie punch — loaded with as many calories and fat as a candy bar! Discover which of your favorite healthy foods are calorically dense and begin to savor every delicious bite.

One of my goals is to help you eat well and make food choices that promote good health, prevent disease, and assist you in achieving (and maintaining) a healthy weight. This new lifestyle will inevitably result in you looking better, feeling better, and ultimately living better.

Weight control is all in the calorie math. To lose weight, you must make changes in both your food intake and exercise patterns such that you reduce your calorie intake below your energy expenditure. When calculating your ideal calorie range to achieve your goals, you need to know a little more about what make ups your energy expenditure side of this equation.

Weight loss = Weekly calories burned greater than weekly calories eaten

Your body burns calories in several ways. To figure out exactly how many you burn each day, also known as your total daily energy expenditure (TDEE), you need to know your basal metabolic rate (BMR) and your general activity level. (The thermic effect of the food (TEF) or the calories burned to metabolize the food you eat also contributes to your TDEE, contributing up to 10 percent.)

Your BMR is the number of calories your body uses while at rest to do the stuff that keeps you alive like breathing; circulating blood; and controlling body temperature, cell growth, brain and nerve function, and contraction of muscles. Your BMR accounts for roughly 60 percent of your daily calorie expenditure. BMR varies from person to person. Factors affecting BMR include your body weight, your height, your gender, your percent body fat and muscle mass, your body temperature, your age, your hormone levels, and your genetic predisposition. Unfortunately, you don’t have much control over your BMR.

Figure 3-1 categorizes the calorie burn side of the equation. The remaining 30 percent of TDEE is physical activity, which then gets broken down into exercise activity thermogenesis (EAT) and nonexercise activity thermogenesis (NEAT). EAT accounts for about 5 percent of TDEE, whereas NEAT can contribute as much as 15 percent. You can see how you have a great deal of control over your dual activity levels, the calorie-burning furnaces: your NEAT and EAT.