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Healthy Weight Loss Tips

Setting a Weight-Loss Goal
Using the BMI formula is one way to lead a happy and healthy lifestyle.

At this point, you've calculated your BMI and waist circumference and discovered whether you are at greater risk of health problems because of those values. You've considered common barriers to weight loss and thought about how to get around them. And you've determined your own health status and family history. The next step is to set a goal.

There are several methods for setting a weight-loss goal. Use one of the methods that follow, whichever suits you best:

1. Use the BMI formula. Estimate a weight that you think will put you in the healthy weight range. Then use the BMI formula from the previous page to refigure the BMI with your goal weight rather than your current weight. If the weight goal you chose falls between 19 and 24.9, then it's a healthy one, and you can use it to determine your daily calorie needs.

2. Lose a percentage. The National Institutes of Health; the National Heart, Lung, and Blood Institute; and the North American Association for the Study of Obesity recommend an initial weight-loss goal of 10 percent of your current weight over a six-month period. Even if you have a lot of weight to lose, aiming for a 10 percent loss will keep you focused on an achievable target. After you lose 10 percent successfully, you can set a new goal. To determine how many pounds equal 10 percent of your weight, do these calculations:

  • Your current weight in pounds ___ X .10 = ___ pounds to lose.
  • Current weight ___ minus ___ pounds to lose = ___ my new weight goal.

3. Lose 1/2 to 2 pounds per week. No matter what your goal weight, the healthiest and most long-lasting weight loss typically occurs in weekly increments of 1/2 to 2 pounds. People who are clinically obese (BMI of 30 or more) can aim for a weekly weight loss at the higher end of that range, while those who are only slightly overweight should aim for the mid or lower end.

Which of these methods you choose will likely depend on your current weight as well as your personal preferences. It doesn't matter much how you set your goal, but it's essential that you have one. A goal will help determine your path to weight loss.

How Many Calories Do I Need?

Now that you have a goal in mind, it's time to make a plan for achieving it. Weight loss requires you to create a calorie deficit: You need to take in fewer calories than you expend over a period of time.

Although you can just start eating less, it will be easier to meet your long-term goal if you have some idea of how many calories you're actually consuming right now. You can get a sense of that by figuring out how many calories you need every day to maintain your current weight. Here's a quick calculation that will give you a ballpark estimate of your daily personal energy needs:

1. My current weight: ___ X 10 (for women) or X 11 (for men) = ___

2. I am:

  • Inactive (mainly sitting, driving a car, standing, reading, typing, or other low-intensity activities): Add 300 to the result of #1
  • Moderately active (active throughout the day with very little sitting; may include heavy housework, gardening, brisk walking): Add 500 to the result of #1
  • Active (active, physical sports or in a labor-intensive job such as construction): add 700 to the result of #1.

3. Total of answers in #1 and #2: ___. That's the approximate number of calories you need every day to maintain your current weight.

Another way to estimate your current calorie intake is to consult this chart from the Dietary Guidelines. The table estimates the number of calories needed to maintain energy balance based on gender, age, and activity level.

Getting to Your Goal

To lose a pound a week, which is a realistic goal, you'll need to create a deficit of 500 calories a day. That's because one pound of body fat is equal to 3,500 calories (500 calories X 7 days = 3,500 calories). You don't want to lose weight much faster than that because it takes time for fat cells, where your body stores the extra calories that you don't use up each day, to give up their bounty. (People who are classified as clinically obese (BMI > 30) and who are aiming for a more significant weight loss, however, can try to create a calorie deficit of up to 1,000 calories per day -- two pounds, or 7,000 calories, a week.)

By creating a calorie deficit each day, you force your body to seek energy from the stored energy in the fat cells. When fat cells release their stored energy, they shrink, getting smaller and smaller until they are empty. But it's a process, and it doesn't happen overnight.

You may have heard about diet plans that promise weight loss of 5 pounds a week -- and you may even have experienced such a drop in weight yourself. But when you lose weight that rapidly, the majority of what's lost is typically water and muscle rather than fat.

Severe food restriction causes chemical changes in the body that produce water as a by-product. That water, and the water loss caused by muscle degradation when the body breaks down muscle to provide energy, is what's actually being lost rather than fat. When you return to a less restricted diet, the body quickly replenishes the depleted fluid and fat stores, and you regain weight. You don't regain muscle unless you work at it.

That's why yo-yo dieting is so unhealthy and unproductive: You actually regain weight as fat rather than muscle -- unless you go to the gym and work to counteract this process. At the more reasonable weight loss rate of 1/2 to 2 pounds a week, you'll lose unhealthy body fat, not just water.

Drastically reducing the number of calories you consume also slows your body's metabolism, which is counterproductive to your weight-loss efforts. A dramatic reduction in calories signals famine, and the body will slow its internal engine to keep you from starving to death. It will give up little bits of muscle instead of fat, because fat is a concentrated source of energy that the body might need if the perceived famine conditions persist. Keep in mind that your metabolism is the greatest user of calories. If it slows down, you're burning fewer calories.

How Many Calories?

To figure out your daily calorie needs to produce a one-pound weight loss per week, take the result of the formula you used earlier in step #3 and subtract 500 from it. The result is the number of calories you can consume each day to achieve a one-pound weight loss.

One caveat: Do not consume less than 1,000 calories per day. Research shows that weight loss is not aided by eating less than 1,000 calories. And the average minimum amount of calories needed to support your body's functions is 1,200 per day. You'll risk your health and defeat your weight-loss goals because you'll slow your metabolism if you go much below that number of calories.

In the next section, we will discuss how to create a calorie deficit that will help you lose weight.
