Geriatric BMI Calculator

Older adults have different BMI targets to preserve muscle mass, mobility, and independence. Calculate BMI and view risk guidance tailored for seniors.

Results

BMI

25.7

Interpretation

Recommended BMI range (22–27) for reduced morbidity risk.

Converted values: Height 165.0 cm • Weight 70.0 kg

How to Use This Calculator

1

Measure height and weight safely

Use a wall-mounted stadiometer and a stable, low-profile scale. Consider seated or recumbent height estimates if standing is difficult.

2

Use geriatric BMI cutoffs

Older adults have a protective window of 22–27 BMI. Values below 22 suggest malnutrition risk; values above 27–30 may increase metabolic risk.

3

Track longitudinal change

Repeated weight loss in older adults predicts frailty. Combine BMI with grip strength, gait speed, and dietary intake assessments.

Formula

BMI = Weight ÷ Height²

  • Metric: weight (kg) ÷ height² (m²)
  • Imperial: weight (lb) ÷ height² (in²) × 703
  • Interpretation differs in geriatrics: aim for 22–27 to balance frailty and cardiometabolic risk.

Full Description

In older adults, slight overweight can protect against hospitalization and falls, while underweight increases risk of sarcopenia and mortality. BMI thresholds shift upward to account for age-related muscle loss and bone density changes.

Underweight

BMI < 22 — assess appetite, swallowing, dentition, and medication side effects.

Optimal

22 ≤ BMI ≤ 27 — associated with better survival and functional independence.

Over range

27 < BMI ≤ 30 — monitor blood pressure, A1C, and mobility.

High risk

BMI > 30 — combine clinical care with nutrition and activity plans to prevent frailty.

Frequently Asked Questions

Why is BMI 22–27 recommended for older adults?

Research shows BMI below 22 is linked to higher mortality and frailty, while BMI 22–27 balances energy reserves with metabolic health.

What if an older adult is bedridden?

Use alternative measurements like knee height or ulna length to estimate stature, then compute BMI. Monitor muscle mass through other assessments.

Should BMI be the sole metric?

No. Combine BMI with functional tests, dietary intake, hydration status, and chronic disease markers.

How often should caregivers track weight?

Monthly tracking is typical. Unintentional loss of ≥5% in 6–12 months warrants medical evaluation.