Abdominal Volume Index (AVI)
The abdominal volume index estimates the volume of the abdomen from waist and hip circumference using a tape measure alone, and it tracks visceral fat and metabolic risk as closely as waist circumference does.
Plain English
Patient-Friendly Explanation
The abdominal volume index is a way of turning two tape measurements into an estimate of how much volume the abdomen contains. It was developed by researchers in Mexico and published in 2003, using the same formulas an engineer would use for a cylinder and a cone. The measurement is simple. A tape is placed around the narrowest part of the waist, and a second measurement is taken around the widest part of the hips. The two numbers are put into a short equation, and the result is expressed in litres. In the original study of 746 adults, a value of about 24.5 litres was the point that separated people with obesity from those without it most cleanly, and people with higher values were more likely to have impaired glucose tolerance and type 2 diabetes, even after age and sex were taken into account. Later studies have found the index performs at least as well as waist circumference for spotting metabolic risk, and in one study of people with type 2 diabetes it was the strongest of three tape-based measures at identifying excess fat around the internal organs. This matters in a weight clinic for one very practical reason: the number on the scales can sit still for weeks while the waist is already shrinking, and the abdominal volume index picks that change up. It needs no scan, no fasting and no equipment beyond a tape measure, so it can be repeated at every visit and written into a chart as a trend. It is an estimate of abdominal size, not a measurement of liver fat or of the fat around the heart, so it is used alongside the other numbers rather than instead of them.
Medical
Clinical Definition
The abdominal volume index (AVI) was proposed by Guerrero-Romero and Rodriguez-Moran as an anthropometric estimate of overall abdominal volume, derived from the volume formulas for a cylinder and a vertical cone: AVI = [2 x (waist circumference in cm)^2 + 0.7 x (waist minus hip in cm)^2] / 1000, which approximates the volume between the symphysis pubis and the xiphoid process and theoretically includes both intra-abdominal and subcutaneous adipose tissue. In the original population-based cross-sectional study of 746 adults in northern Mexico, receiver operating characteristic analysis identified 24.5 litres as the cut-off for estimating obesity, and logistic regression adjusted for age and sex gave higher odds ratios for impaired glucose tolerance (1.6, 95% CI 1.1-9.1, p=0.01) and type 2 diabetes (2.1, 95% CI 1.3-7.9, p=0.001) than waist-to-hip ratio, body mass index, waist circumference or the truncated-cone model. Subsequent validation has been consistent if not uniform. In a cross-sectional study of 221 patients with type 2 diabetes in Ghana using bioelectrical impedance as the reference, AVI outperformed the conicity index and waist-to-hip ratio for detecting visceral adiposity, with an area under the curve of 0.89 in both sexes against 0.68 and 0.73 in men, optimal thresholds of >15.56 in men and >18.49 in women, and the strongest age-adjusted correlation with visceral fat (r=0.787 in men, r=0.770 in women). In a Spanish occupational cohort of 193,462 workers, AVI cut-offs of 17.59 in men and 13.70 in women predicted metabolic syndrome under International Diabetes Federation criteria, and a study using three-dimensional body surface scanning reported that each additional litre of abdominal volume carried a 56% higher likelihood of metabolic syndrome, with median cut-offs of 12.8 litres in men and 9.5 litres in women. In adolescents, AVI and waist circumference were the two indices with areas under the curve above 0.8 for metabolic syndrome when IDF criteria were applied. The index inherits the limitations of all circumference-based measures: it cannot separate intra-abdominal from subcutaneous fat, it is affected by hip circumference measurement error and by body shape, it is weighted heavily towards waist size, and the published cut-offs differ between populations and between men and women, so the trend within an individual matters more than a single reading against a fixed threshold.
Key Insight
Why It Matters
When the scales stall but the waist is still coming down, the abdominal volume index turns two tape measurements into a number that shows the change - useful evidence that the plan is working even when weight is not moving.
Sources
Reviewed against standard medical references.
Medically reviewed by
Family Physician & Registered Acupuncturist, Accord Medical Clinic. MBBS (NUS), Graduate Diploma in Family Medicine (NUS), Graduate Diploma in Acupuncture (Singapore College of TCM).
Last reviewed: October 2026
This page is general health education, not medical advice. Whether any treatment is appropriate for you is a decision made in consultation after assessment.
