Nutrition For Dummies. Carol Ann Rinzler
Читать онлайн книгу.restricting your diet — or being born again with a different body, preferably with light bones and no curves. Others are more reasonable.
Weight charts and tables
In 1959, the Metropolitan Life Insurance Company published the first set of standard weight charts. The weights were drawn from insurance statistics showing what the healthiest, longest-living people weighed — with clothes on and (for the women) wearing shoes with one-inch heels. The problem? At the time, the class of people with insurance was so small and so narrow that it was hard to say with certainty that their weight could predict healthy poundage for the rest of the population.
Thirty-one years later, the government published the weight chart shown in Table 4-3. This moderate, eminently usable set appeared in the 1990 edition of Dietary Guidelines for Americans (more about the Dietary Guidelines in Chapter 16). The weights in this table are listed in ranges for both men and women of specific heights. Height is measured without shoes, and weight is measured without clothes. Because most people gain some weight as they grow older, the people who compiled these recommendations did a really sensible thing: They divided the ranges into two broad categories, one for people age 19 to 34, the other for those age 35 and older.
TABLE 4-3 How Much Should You Weigh?
Height | Weight (Pounds) for 19- to 34-Year-Olds | Weight (Pounds) for 35-Year-Olds and Older |
---|---|---|
5’ | 97–128 | 108–138 |
5’1” | 101–132 | 111–143 |
5’2” | 104–137 | 115–148 |
5’3” | 107–141 | 119–152 |
5’4” | 111–146 | 122–157 |
5’5” | 114–150 | 126–162 |
5’6” | 118–155 | 130–167 |
5’7” | 121–160 | 134–172 |
5’8” | 125–164 | 138–178 |
5’9” | 129–169 | 142–183 |
5’10” | 132–174 | 146–188 |
5’11” | 136–179 | 151–194 |
6’ | 140–184 | 155–199 |
6’1” | 144–189 | 159–205 |
6’2” | 148–195 | 164–210 |
6’3” | 152–200 | 168–216 |
6’4” | 156–205 | 173–222 |
6’5” | 160–211 | 177–228 |
6’6” | 164–216 | 182–234 |
From Nutrition and Your Health: Dietary Guidelines for Americans, 3rd ed. (Washington D.C.: U.S. Department of Agriculture, U.S. Department of Health and Human Services, 1990)
Muscle is heavier than fat, so individuals with a small frame and proportionately more fat tissue than muscle tissue are likely to weigh in at the low end. People with a large frame and proportionately more muscle than fat are likely to weigh in at the high end. As a general but by no means invariable rule, that means that women — who have smaller frames and less muscle — weigh less than men of the same height and age.
Later editions of the Dietary Guidelines omitted the higher weight allowances for older people so that the “healthy” weights for everyone, young or old, became the ones listed in 1990 in the column for 19- to 34-year-olds. I’m going to go out on a limb here to say that I prefer the 1990 recommendations because they are
Achievable without constant dieting
Realistic about how your body changes as you get older
Less likely to make you totally crazy about your weight
AGE IS NOT JUST A WEIGHT NUMBER
Losing weight to stay healthily slim is generally regarded as a positive thing, but in 2019, a study published in the British Medical Journal showed that there could be problems associated with losing weight later in life. Based on data gathered from 36,000 subjects in the U.S. National Health & Examination Survey, it turns out taking off pounds in middle age and late adulthood may actually raise your risk of dying prematurely, especially if you have an underlying medical condition such as diabetes, cancer, or heart disease. The important message from the researchers: “Try not to gain weight while you’re young and when you’re older focus on maintaining a healthy lifestyle.”
These are a pretty good description of how nutritional guidelines need to work, don’t you think?
The BMI: Another way to rate your weight
The body mass index (BMI) is a number that measures the relationship between your weight and your height. Currently in the United States, a BMI below 18.5 is considered underweight, 18.5 to 24.9 is normal, 25.0 to 29.9 is overweight, 30.0 to 39.9 is obese, and 40.00 or greater is severely obese. Previously, other countries were slightly more lenient in their estimate of normal and overweight; for example, in Australia, a BMI of less than 20 was considered underweight. Today, the American standards are generally accepted around the world.
The equation used to calculate your BMI is called the Quetelet Index, named after the 19th-century Belgian mathematician and astronomer who invented the concept of “the average man” (see the nearby sidebar “The man who invented the average man”). The equation is W/H2, which originally meant weight (in kilograms) divided by height (in meters, squared). The American equation, however, divides your weight in pounds by your height in inches, squared. So if you are five foot three inches tall and weigh 138 pounds, the U.S. equation looks like this:
BMI = W/H2 x 705= (138 pounds/63 x 63 inches) x 705= (138/3,969)