Interpreting Your DEXA
DEFINITIONS:
ANDROID/GYNOID RATIO: The “apple” to “pear” ratio describes where body fat is stored. Android shapes store fat around the abdomen and gynoid shapes store fat around the hips. From a metabolic health standpoint, we like women to be around 0.8 and men to be around 1.0. Ratios under 1.0 indicate a pear shape and over 1.0 indicate an apple shape.
ALMI (appendicular lean mass index): the amount of lean mass in the arms and legs relative to height. Higher ALMI values have strong correlation to longevity and overall health, whereas low values are a risk factor for sarcopenia, the gradual loss of muscle mass, strength and function
BONE DENSITY: The denseness of the bones is used to predict osteopenia and osteoporosis, or bone degeneration disease. Reports provide a Z-score and a T-score. Z score compares bone density to what is deemed “normal” for other people in a similar age bracket and body size. Think of it as a peer comparison. T-score compares bone density to a 30 year old, which is considered the “standard”. A score higher than -1.0 is considered normal bone density. Values from -1.0 to -2.5 indicate there is a risk for osteopenia and values below -2.5 indicate a risk for osteoporosis.
DEXA (dual x-ray absorpitometry): The gold standard for body composition analysis and the most accurate way to calculate body fat percentage, fat free mass, VAT and ALMI
FFM (fat free mass): The amount of mass in your body that is not composed of fat. This includes, muscle, bone, organs, and connective tissue. We use this number to determine caloric need to keep the body functioning optimally as well as the number at which LEA (low energy availability) becomes problematic.
LEA (low energy availability): In short, this means a person is not eating enough calories to match training demand. This can have profound negative effects on body composition, overall health and athletic output. We can calculate LEA levels from FFM and also calculate ideal caloric intake to prevent negative health outcomes
VAT (visceral adipose tissue): Hormonally active fat. This is the amount of fat around the internal organs. We need this fat but too much correlates with increased risk of diabetes and heart disease. Values under 100 are considered low risk. Values from 100-160 are considered elevated risk and modifiable lifestyle factors need to be addressed. VAT over 160 is high risk, which is a serious concern that should be addressed to prevent heart disease, stroke, and diabetes.
DEXA BONE DENSITY REPORT
T score and Z score can be found on the bottom row of the data table. The green/yellow/red box shows your values plotted against T scores on the right. Values in the green are “normal bone density”. Values in the yellow are at risk for osteopenia and those in the red are at risk for osteoporosis. Vitality offers dedicated bone denisty testing for those concerned about osteopenia or osteoporosis. This scan is a more specific bone density test than that done with the body composition scan.
DEXA BODY COMPOSITION
Heat map: bone, muscle and fat color coded to show actual distribution in your body. Color guide is under the pictures.
Body composition results: Each part of the body broken down to grams of fat, grams of muscle and bone, percent total mass and numbers matched against peers (AM) and a healthy 25 year old (YN)
Percent fat total is your body fat percentage.
Body % percentage plot: Your body fat percentage plotted against your peer group for age and demographics
BMI: Body mass index which takes total weight and divides by height. This does not take body composition into account.
Adipose Indicies: Your fat numbers. The numbers we look at in this box are total body % fat, android/gynoid ratio, and Est VAT Area. Android/gynoid ratio is optimal when <0.8 for women and <1.0 for men. This is the apple/pear shape indicator. VAT area is the visceral adipose fat indicator. Less than 100 is optimal. 100-160 is at risk and over 160 is high risk for cardiovascular disease and metabolic disease. If less body fat to height is your goal, you want to see a lower number in the AM category with total body % fat.
Lean Indicies: Your muscle numbers. Lean muscle/height is your muscle mass divided by height. Ideally, the AM number will be higher, to indicate high muscle mass compared to height. However some people do not put on muscle mass as easy as others. They may have a lot of muscle for their frame and we can assess this using ALMI to determine muscle mass density. ALMI index is the amount of lean mass compared to height and is a strong indicator of longevity. In women, we like the index (result) >5.5 and in men, over 7.