Читать книгу Intermittent Fasting For Dummies - Janet Bond Brill - Страница 34

Doctors use a mass screening tool to give them another quick way to instantly see if their patient’s weight puts their patient at risk for health problems. The body mass index (BMI) is a good estimate of body fat, based on height and weight, that applies only to adult men and women.

The National Institutes of Health (NIH) defines BMI categories as such:

 Healthy weight: 18.5 to 24.9

 Overweight: 25 to 29.9

 Obese: 30 or greater

You want to aim for a healthy BMI of less than 25. Figure 2-1 shows a BMI chart where you can look up your BMI.

The National Institutes of Health (NIH) has a great BMI calculator at www.nhlbi.nih.gov/health/educational/lose_wt/BMI/bmicalc.htm that does the work for you.

Source: www.nhlbi.nih.gov/health/educational/lose_wt/BMI/bmi_tbl.pdf

FIGURE 2-1: Body Mass Index chart.

If you like numbers and want to do the calculations yourself, then use this equation:

Here’s how this equation works:

Use Debbie from the previous section. If you input her height and weight into the online BMI calculator, you come up with a BMI of 26.6, a number greater than 25, so Debbie is overweight. How much weight would Debbie have to lose to get to a BMI of 25? For her height she’d need to weigh a little less than 150 to get to a BMI of 25, so in this case she would set a long-term weight loss goal of 11 pounds. I suggest you use this method for an accurate calculation when you’re setting your initial weight-loss goals.

A healthy and safe rate of weight loss that virtually guarantees you’re losing almost all body fat and not precious muscle mass is a maximum of 1 to 2 pounds per week. Furthermore, experts have shown that people who lose weight gradually and steadily are more successful at keeping weight from returning.

However, the BMI calculation does have its limitations, which include the following:

 It may overestimate body fat in athletes and others who have a muscular build.

 It can underestimate body fat in older persons and others who have lost muscle.