THE BLOG

The Perfect Weight-Loss Romance: Diet Meets Exercise

12/18/2012 08:09 am ET | Updated Feb 17, 2013

So you're fed up with the "banana diet," the "spinach soup diet," or the "no this, no that" diets that you've tried in the past -- but what now? In this moment of frustration, a brilliant plan pops into your head, and you say to yourself, "What if I just eat what I want and exercise five times a week?" Seems like a valid plan. If you are burning all of those calories, you should be able to eat a moderate diet and lose weight, right? Not necessarily, and I'll explain why.

Recent studies by Dr. Timothy Church and others help explain why people stick with low-calorie diets more readily than they continue with a regimen of exercise to drop pounds. The principle finding of these studies is that human metabolism appears to be less revved by activity than was once believed. The expectation, for most people, is that adding exercise to their regimen will dramatically speed up their weight loss. While exercise certainly contributes to weight loss, the increase that may occur in one's metabolism due to higher levels of physical activity often has only a small effect on total weight lost over a given period of time. This fact, and recent findings regarding how exercise may contribute less in the weight-loss equation than conventional wisdom dictates, casts new light on the importance of adequate nutrition in achieving your weight-loss goals.

Let's use some national statistics for American women as an example. It is widely accepted that, as a general rule of thumb, it takes a calorie deficit of 500 per day to lose a pound of weight in a week. That's a total of 3,500 calories that must be cut from your diet over a seven-day period, or that must be burned through physical exercise. Given that the average American woman is about 5 foot 4 inches tall, and weighs about 165 pounds, she would have to run about four miles per day in order to add an additional pound of weight loss each week.

While the example above will not hold true for every American female due to differences in body composition and metabolism, it does show the extent to which a person would have to exercise in order to lose significant amounts of weight. For this reason, it is imperative that any weight-loss attempt be centered on proper nutrition, with exercise and physical fitness playing a complementary role. To put things into further perspective, here is a helpful weight-loss calculator that illustrates weight loss as a function of age, gender, current weight and height, and expected caloric restriction (deficit).

Every day, I see new patients in my practice who want help with losing weight. If they are currently not exercising, I ask them not start. Yes, you read that right -- I actually tell them to hold off on the exercise at first if it is not already a part of their daily routine. Not surprisingly, most people are shocked to receive this kind of advice from a medical doctor. They've heard all their lives that exercise is the key to weight loss, and here I am, an expert in the field, advising against it in the first weeks of their program. It begins, however, to make a bit more sense when I explain the rationale behind this uncommon recommendation.

Especially initially, nutrition and diet are so much more important than exercise. If you are trying to adjust to a new lifestyle, you only have so much time. If you go to the gym and work hard for 45 minutes, drive home, and arrive tired and hungry, you are likely to neutralize the calories you burned by grabbing what is quick and easy. You may have burned 250 calories at the gym, but you can just as easily drink hundreds of calories by grabbing a sports drink, or while grazing as you decide what to eat. It is equally likely that the new investment of time in not only eating healthy, but also exercising, may result in burnout of one, the other, or both. For this reason, I ask my patients to take a few weeks, or even months, adjusting to a new way of eating. They need to ensure that they eat enough, are eating high-quality foods, and that their consumption is spread out over the day to have the best metabolic effect.

While exercise does not add that much to weight loss initially, it is proven to help people maintain weight loss in the long term. In addition, the health benefits of exercise are huge, as are the improvements in overall well-being. So many of my patients share that they exercised faithfully early on in their program, lost no weight, and consequently gave up. It is so important to understand how diet and exercise work in the process of weight loss in order to remain empowered, and not frustrated, as you implement a healthy new lifestyle.

There are important factors and a fine balance that must be obtained in order to make diet and exercise work together efficiently. Since diet and exercise plans are often created separately, it makes for a less successful end result. My suggestion is that when you are ready to add exercise into your routine, you design your meals in coordination with your exercise regimen. This way, your body can utilize the correct nutrients to make your exercise efforts as effective as possible.

In cleaning up your diet, a good place to start is by cutting out unhealthy snacks. When you eat one ounce of potato chips, the result is a caloric intake of roughly 150 calories, 14 grams of carbohydrates and 10 grams of fat. Taken together, this means that the average American woman would have to either run a little over a mile, or walk almost two, in order to burn enough calories to neutralize this intake.

A diet containing lean proteins, healthy fats, and carbohydrates in the form of non-starchy vegetables is the best thing you can do to ensure that your weight-loss efforts are maximized. Adding exercise is a major plus, and will only help to keep your weight-loss progress going. Just remember that it should not be your primary focus, early on.

Before putting all of your energy (literally) into your workouts, be sure that you are prepping yourself by eating the foods that provide you with the nutrients your body needs. A successful pairing of exercise and nutrition is not beyond your reach! If you are serious about losing weight, educate yourself on the nutritional value of the foods you eat. Next, chose an eating regimen that is right for you. There are countless resources available for those serious about weight loss.

For more of my advice, click here.

For more by Caroline J. Cederquist, M.D., click here.

For more on weight loss, click here.