This is another column in a series about obesity and how to lose weight, taken from Dr. Greger’s 2020 book “How Not to Diet.” People often say the reason they gained weight is that they haven’t been exercising enough. The junk food industry would like us to believe that the reason Americans are getting heavier is that they don’t exercise enough. But what are the facts?
Without question, regular exercise is key for optimal health. It helps people live longer and improves quality of life as they age. It reduces risk of breast and colon cancer, diabetes, depression, erectile dysfunction, gallstones, high blood pressure, heart attacks, strokes, diabetes, depression and bone loss. It also helps maintain weight loss.
People who exercise vigorously several times a week, such as marathoners and ultramarathoners, burn up enough calories to lose a significant amount of weight. But for the rest of us, what we eat (or don’t eat) is much more important for weight loss than exercise. Following are some examples of the amount of exercise needed to burn extra calories from various foods:
• You’d have to jog a quarter of a mile to work off every bite of a Snickers bar.
• If you eat two boiled chicken legs with the skin removed, you’d have to run three miles at a pace of 5 miles per hour.
• A slice of pizza is about 300 calories, and you’d have to walk briskly (3-4 miles mph) for an hour per slice.
• If you buy your child a Happy Meal, they would need to run for two hours.
• If you eat a doughnut, you’d have to climb the Empire State Building’s 86 flights of stairs.
• If you order supersized French fries, you’d have to run 3 miles.
• If you choose chicken salad over garden salad you’d have to run an extra 3 miles.
• A blueberry muffin has 265 calories, and to work that off you’d have to walk briskly for 48 minutes or run for 25 minutes.
• A medium mocha coffee has 290 calories, which would require 53 minutes of brisk walking or 28 minutes of running.
Dr. Greger makes the point that “most overweight individuals choose exercise as their first approach to weight loss.” This unrealistic hope leads to disappointment and “abandonment of weight-loss efforts altogether.” The misconception that exercise leads to weight loss also gives overweight people a license to eat more — they think they burned up a lot of calories by exercising and that they are therefore entitled to indulge in eating more food. Another thing about exercise is that it increases appetite, causing people to eat more calories.
It’s not that moderate exercise doesn’t result in any weight loss. Studies show that 45 minutes of brisk walking four times a week for three to four months results in loss of 6 pounds of body fat. Whether you need to lose weight or not, by all means exercise regularly. But if losing weight is your goal, it’s most important to be mindful of what you’re eating.
Greg Feinsinger, M.D., is a retired family physician with a special interest in heart disease and diabetes prevention and reversal, ideally though lifestyle changes. He’s available for free, one-hour consultations — call 970-379-5718.