While “eat less, exercise more” is as simple a plan as you’re going to find, it does help to understand some of its underlying principles–and I don’t even have to write a book. (If cutting food and increasing exercise doesn’t work you should go for a checkup: A number of medical conditions, most notably low thyroid function, can interfere with weight loss.)
The food you eat is used for two things. First, your body needs fuel for your daily activities, including the stuff you don’t even think of: respiration, circulation, brain function and the rest. The amount of energy you expend on these activities is called your basal metabolic rate (BMR); total energy expended equals BMR plus movement (exercise) energy plus the energy consumed by digestion itself.
The fuel value of food is calibrated in calories. If you take in more calories than you expend, your fat stores and weight both increase. The excess food energy simply has no place else to go.
A pound of fat contains about 3,500 calories, so if on a daily basis you burn 500 more calories than you take in you should lose a pound a week: 500 x 7 = 3,500.
One way to estimate your body fat is to measure your body mass index (BMI). Based on a ratio of weight to height, BMI is calculated using a special chart (to find the chart, go online to http://www.nhlbisupport.com/bmi/). Normal-weight BMIs fall between 18.5 and 24.9 and overweight between 25.0 and 29.9; obesity starts at 30.
To maintain your current status, keep your calorie intake in line with your activity level:
o If you are sedentary (less than 30 minutes of daily exercise): 1,600-1,800 calories for women, 2,000-2,400 for men
o If you are moderately active (30-60 minutes of moderate daily exercise): 1,800-2,400 for women, 2,400-2,600 calories for men
o If you are active (60 minutes or more of moderate exercise daily): 2,000-2,400 calories for women, 2,600-3,000 for men
It stands to reason that to lose weight, you should take in fewer calories than what’s listed. Don’t want to fiddle with the math? Just figure that if you cut your regular food intake your BMI, body fat percentage and weight will all fall, even without measuring every calorie you put in your mouth. You can also go online and use the BMR Calculator at this web site:
http://www.room42.com/nutrition/basal.shtml
Cutting portions is one way to cut calorie intake. It’s not always easy to judge portion sizes–who can estimate something like a half-cup by eye? To get around that dilemma, use the following visual guide:
o 3 ounces cooked meat: the size of your palm
o 1/2 cup vegetables or beans: rounded handful
o 1/2 cup cooked pasta or rice: one small ice-cream scoop
o 1 medium piece fresh fruit: the size of a baseball
o 1/4 cup dried fruit: the size of a golf ball
o 1/3 cup nuts: level handful
o 1 ounce cheese: 4 dice
Cutting portions does not mean skipping meals, especially breakfast–not eating all day will only set you up for an all-night binge and a decreased metabolism–just the opposite of what you want to do. Low-sugar granola with low-fat yogurt is both filling and nutritious, as is whole-wheat bread topped with peanut butter. If you have a little more time, try some oatmeal with soymilk, raisins and cinnamon.
The second approach to cutting calories involves eating more filling, nutritious foods and less (not none) of such weight makers as chips, cookies, candy and cake. The good stuff isn’t as calorie dense; that is, it doesn’t have as many calories in a given volume of food. One rule of thumb is to go for foods with more water in them, such as soups, most fruits (bananas are a high-calorie exception), cooked whole grains and, especially, non-starchy vegetables. Except for the soup, these foods tend to be rich in fiber, which also helps your stomach say “enough.”
Fewer calories coming in is only half of the weight-loss equation; more calories going out is the other. That means getting enough physical activity to keep the energy stored in the foods you eat from becoming energy stored as fat in your body. Exercise comes in two forms: aerobic and resistance. Aerobic activities, such as walking, jogging, bicycling and running, force the heart and lungs to work harder than normal. This burns fat and improves your fitness level–that is, the amount of exercise you can perform before getting winded. Resistance activities, such as lifting weights or using various exercise machines, increase muscle strength and mass. Since muscle cells burn more calories than fat cells, upping your basic metabolic rate, that’s a good thing. (Remember that since muscle is also heavier than fat, your weight may not go down. Don’t fret–what counts is losing INCHES!)
You need to exercise aerobically every day–walking is a great start, especially if you been inactive for a while. Don’t overdo resistance work, though: Since the muscle grows in the rest period after a workout, three times a week is plenty. Trying to play Superman or Wonder Woman in the weight room leaves you liable to injury. Actually, the best way to work with weights is to take at least a lesson or two with a personal trainer, who can help you find the activities that best suit your needs.
Lastly, take all those diet books with a grain of salt. Weight loss isn’t about trying one hard-to-follow plan after another. It’s about eating less, exercising more–and finding a healthy way of life you can be happy with for a lifetime.
David Wygal, CN, is a Certified Nutritionist with over 20 years of experience in the health and nutrition industry.
