## Calculating ideal body weight (IBW)

Ideal body weight is calculated to help determine an appropriate weight for height or to determine a long term weight loss goal.

When estimating an Ideal Body Weight or Goal Weight for overweight and obese clients we recommend that you use the ‘Adjusted Ideal Body Weight’ calculation.

This equation allows for 25% of excess metabolically active body weight (lean muscle mass), giving you a more appropriate estimate of an Ideal Body Weight for that individual.

Just aiming for the healthy weight range for height or a BMI of 25 may not be appropriate or realistic for all patients.

It is also important to remember that even a 5-10% weight loss can result in significant reductions in co-morbidities. So even though you may be working to a long term weight loss goal, small incremental weight losses can result in large health benefits.

The equation for calculating Adjusted Ideal Body Weight is;

### Adj IBW = [(Actual Body Weight –IBW) x 0.25] + IBW

Where IBW = Weight at BMI 25

The table below allows you to work out what the IBW at a BMI of 25 is for your patient’s height

Height in cm Ideal weight range Weight at a BMI of 25
140 39-49 49
142 40-50 50
144 41-52 52
146 43-53 53
148 44-55 55
150 45-56 56
152 46-58 58
154 47-59 59
156 49-61 61
158 50-62 62
160 51-64 64
162 52-66 66
164 54-67 67
166 55-69 69
168 56-71 71
170 58-72 72
172 59-74 74
174 61-76 76
176 62-77 77
178 63-79 79
180 65-81 81
182 66-83 83
184 68-85 85
186 69-86 86
188 71-88 88
190 72-90 90
192 74-92 92
194 75-94 94
196 77-96 96
198 78-98 98
200 80-100 100