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Definition of Body mass index

Body mass index: A key index for relating a person's body weight to their height. The body mass index (BMI) is a person's weight in kilograms (kg) divided by their height in meters (m) squared.

The National Institutes of Health (NIH) now defines normal weight, overweight, and obesity according to the BMI rather than the traditional height/weight charts. Since the BMI describes the body weight relative to height, it correlates strongly (in adults) with the total body fat content.

Overweight is defined as a BMI of 27.3 % or more for women and 27.8 % or more for men, according to the NIH. Obesity is defined as a BMI of 30 and above, according to the NIH. (A BMI of 30 is about 30 pounds overweight.) Note, however, that some very muscular people may have a high BMI without undue health risks.

The table below has already done the math and metric conversions. To use the table, find the appropriate height in the left-hand column. Move across the row to the given weight. The number at the top of the column is the BMI for that height and weight.

BMI
(kg/m2)		 19 20 21 22 23 24 25 26 27 28 29 30 35 40
Height
(in.)		 Weight (lb.)
58 91 96 100 105 110 115 119 124 129 134 138 143 167 191
59 94 99 104 109 114 119 124 128 133 138 143 148 173 198
60 97 102 107 112 118 123 128 133 138 143 148 153 179 204
61 100 106 111 116 122 127 132 137 143 148 153 158 185 211
62 104 109 115 120 126 131 136 142 147 153 158 164 191 218
63 107 113 118 124 130 135 141 146 152 158 163 169 197 225
64 110 116 122 128 134 140 145 151 157 163 169 174 204 232
65 114 120 126 132 138 144 150 156 162 168 174 180 210 240
66 118 124 130 136 142 148 155 161 167 173 179 186 216 247
67 121 127 134 140 146 153 159 166 172 178 185 191 223 255
68 125 131 138 144 151 158 164 171 177 184 190 197 230 262
69 128 135 142 149 155 162 169 176 182 189 196 203 236 270
70 132 139 146 153 160 167 174 181 188 195 202 207 243 278
71 136 143 150 157 165 172 179 186 193 200 208 215 250 286
72 140 147 154 162 169 177 184 191 199 206 213 221 258 294
73 144 151 159 166 174 182 189 197 204 212 219 227 265 302
74 148 155 163 171 179 186 194 202 210 218 225 233 272 311
75 152 160 168 176 184 192 200 208 216 224 232 240 279 319
76 156 164 172 180 189 197 205 213 221 230 238 246 287 328


 Body weight in pounds according to height and body mass index.

Below is a table identifying the risk of associated disease according to BMI and waist size.
BMI Category Waist less than or equal to 40 in. (men) or 35 in. (women) Waist greater than 40 in. (men) or 35 in. (women)
18.5 or less Underweight N/A N/A
18.5 - 24.9 Normal N/A N/A
25.0 - 29.9 Overweight Increased Risk High Risk
30.0 - 34.9 Obese High Risk Very High Risk
35.0 - 39.9 Obese Very High Risk Very High Risk
40 or greater Extremely Obese Extremely High Risk Extremely High Risk
Source: MedTerms™ Medical Dictionary
http://www.medterms.com/script/main/art.asp?articlekey=16125
Last Editorial Review: 10/15/2004


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