The Skinny on Obesity: Part III
Low carb and high fat diets, high carb low fat diets, exercise programs named with mental illness monikers, shoes designed to tone and firm the bottom, pillows designed to keep us cool while we sleep… What’s next for a nation of consumers who got into trouble consuming too much in the first place?
In the second of this four part obesity series, my friend and coworker Ellen Thornburg identified and discussed increases in portion sizes, decreases in physical activity, and faulty sleeping patterns as causes for obesity. And while obesity, like other chronic diseases, is complex in its nature, it is hard for any expert to argue that eating less, moving more, and sleeping better would not remedy the problem for most Americans.
As the first paragraph suggests, finding our way out of this massive problem can seem complicated, though it need not be this way. Now, I know the mind loves novelty, but all the fads in the world can’t replace a healthy lifestyle that includes a nutrient rich diet, physically active lifestyle, and adequate time to rest.
To discuss how exercise and diet can influence weight, we must discuss the concept of energy balance. This concept is governed by the Law of Conservation of Energy/Mass (given that Einstein is right), and thus weight loss, weight gain, and weight maintenance are governed by how many calories we consume and how many calories we burn. Simply put, you can lose weight on a cheesecake diet, as long as you burn more calories than you consume. To elaborate, think of your adipose tissue (fat cells) as a bank account. If we want a big bank account we spend less and save more. The opposite occurs when we go broke; we spend more money than we put in. This same intuition applies to our bodies. If we want to lose weight we must expend more calories than we take in.
On to some application. To find out how many calories you body needs daily go to this calculator and enter the required information. This tool will give you two numbers, the Basal Metabolic Rate (BMR), which is about how many calories your body would consume during the day if you were at rest, and a daily energy expenditure estimate, which will be the higher of the two numbers and takes into account the caloric cost of your physical activity plus your BMR. To lose weight, eat enough calories to match the BMR number, and let the energy for physical activity come from your adipose tissue.
For example, a sedentary 6 foot 175 lbs male would need roughly 1842 calories to meet the BMR, and 2579 to meet the energy needs for physical activity. Instead of eating 2579 calories per day, eat enough calories to match the BMR of 1842. Doing this will create a caloric deficit that will lead to losing weight at about 1.5 pounds per week. Numbers will vary for different body sizes and ages, but the most important thing to remember about losing weight is to burn more calories than we take in. This method is safe, effective, and ensures that your body is getting enough calories to function properly, unlike many low calorie diets. For the best result, pack in those BMR calories with whole foods, such as fruits, vegetables, whole grains, and lean meats. In doing this you will find that you can eat higher volumes of food, which can lead to satisfaction and fullness.
Adding formal exercise into the equation will lead to a greater caloric deficit at the end of the day. The American College of Sports Medicine recommends 150 minutes per week of moderate aerobic activity. This time must be thought of as extra physical activity done with the intention of improving your health, thus gardening, house cleaning, and running back and forth to the copier does not count. If all we need is 150 minutes per week of extra physical activity, dividing 150 by 7 days per week equals roughly 20 minutes of brisk walking per day. Additionally, these 20 minutes can be broken into five or 10-minute segments, so working in your daily exercise does not have to be the time drain you think.
You can expect to burn anywhere from 100 to 200 calories per day by doing the extra time. Though the numbers seem small compared to eating less, they add up over time and contribute to your calorie deficit. What’s more, exercise leads to a longer healthier life, lower blood pressure, better cholesterol, and feeling of well-being. In short, it’s free medicine.
According to the National Sleep Foundation, exercise, diet, and sleep are interrelated. Thus, not catching you Zz’s can feed into the downward spiral of obesity. For instance, a tired person is less likely to eat well and exercise, although these are the key ingredients to a better night’s sleep. In turn, being overweight or obese can increase the risk of sleep apnea, or the temporary cessation of breathing while sleeping, which, in and of itself makes weight loss more difficult. Visit this site to read more about how exercise, sleep, and diet are interrelated, and to learn more tips that will help you get a better night’s sleep.
In short, remember that weight loss is not rocket science, yet popular media complicates the issue to make money. Eating less, moving more, and getting adequate rest works for weight loss and will prevent and cure obesity. Stay tuned for the fourth and final installment of this series by Ellen Thornburg.
Mike Clark is an Exercise Physiologist and Personal Trainer at Duke Center For Living’s Health and Fitness Center. He received his BA in Exercise and Sports Science from UNC.