By Dr. Joseph Mercola
     with Rachael Droege

In regard to weight, the majority of Americans are concerned with overweight and obesity, and rightfully so as two-thirds of U.S. adults fall into this category. However, being thin is not the same thing as being healthy, and it’s important to realize this whether you are trying to lose extra pounds or keep your weight at an unrealistic level.

It is possible to be thin and unhealthy, just as it is possible to be slightly overweight and healthy.

So how thin is too thin? BMI (body mass index) is often used to gauge whether a person is within their ideal weight range (a BMI of less than 19 for women and less than 20 for men is considered underweight), but I consider waist circumference a better measure because it reflects body density. Your waist circumference should be measured by placing a tape measure around the smallest area below your rib cage and above your belly button.

For men:

• Ideal waist measurement: between 31 and 36 inches
• Overweight: between 36 and 40 inches
• Obese: over 40 inches

For women:

• Ideal waist measurement: between 28 and 33 inches
• Overweight: between 33 and 37 inches
• Obese: over 37 inches

If your waist measurement falls significantly below the ideal waist measurement, then you may be underweight. Of course, variations in an individual’s body size and shape may alter the accuracy of this measurement, and the above recommendations should only be used as a guideline to ideal weight, not a definitive definition.

As with overweight and obesity, being underweight poses the risk of a variety of health problems including:

• Malnourishment
• Anemia
• Osteoporosis
• Fertility problems
• Heart irregularities
• Amenorrhoea (loss of periods in women)
• Depression
• Hormone production problems
• Greater risk of early death
• Problems with pregnancy including a greater risk of having a low birth-weight baby and premature delivery
• Lowered resistance to infection
• Chronic fatigue
  

Being underweight may pose an even greater risk as you age, as osteoporosis occurs more frequently in 'thin' people later in life, and body fat helps to maintain estrogen levels in women. Further, a study found that after age 55 people who are five to 10 pounds overweight tend to live longer and have fewer chronic diseases than those who are thin, and after age 70 those who are 5 percent to 10 percent overweight tend to live longer.

There are many reasons why a person may be underweight, such as an improper diet, illness or trying to stay excessively thin for cosmetic reasons. This latter reason is especially common among females in middle school, high school and college, and many who are far from overweight believe they are obese and often adopt bizarre diets, starve themselves, take laxatives, or binge and purge.

These types of eating disorders, including anorexia and bulimia, are epidemics among this population, dangerous ones at that, as mortality rates are as high as 20 percent. Further, research has shown that half of college women have experienced eating disorder symptoms, although most do not have full-blown anorexia or bulimia.

If a person is excessively underweight for these reasons, it is important that they seek to resolve the underlying emotional challenges that are causing this behavior. EFT seems to be a profoundly effective tool for resolving this issue, however, it is not something that you would want to treat as a novice. It would be best to seek a trained therapist for assistance.

For those who are underweight and are trying to gain weight, determining your metabolic type is an essential step. Your nutritional type lets you know how readily you convert excess carbohydrate to fat or how able you are to digest protein efficiently. People who are carbohydrate nutritional types will be able to tolerate grains far better than protein types, who are naturally suited to a diet with little or no grains.

Whether you are a carb nutritional type, a mixed type or a protein type, nutritional typing will allow you to choose foods that your body can utilize and digest properly. You may need a high-protein diet, or you may need a high-carb diet (mostly vegetable carbs) to reach your ideal weight. There is no one approach that will work for everyone, but once you eat the food that your nutritional type was meant to eat, you will naturally gain weight, lose weight or maintain your current weight, depending on your need, and you won’t feel hungry or deprived.

My new book, "Dr. Mercola’s Total Health Program," includes a basic test to learn and understand your own nutritional type along with the means to gear your diet precisely toward the foods that are right for you (and that also satisfy you!). I strongly encourage you to read this book if you are struggling with weight issues, as it will gear you toward a new way of looking at food and nutrition. Your diet should be focused on providing your body with the most nourishing foods, not those that you think will make you gain or lose weight. Once you begin to follow this principle, you’ll see that your weight will normalize naturally.

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