Android to Gynoid Fat Ratio: What Your DEXA Scan Reveals About Heart Disease Risk

If you have ever had a DEXA body composition scan, you will have seen a line on the report marked A/G ratio. It is often skipped over in favour of the more familiar numbers like body fat percentage or visceral fat mass. In reality, the android to gynoid fat ratio is one of the most useful single figures on the entire report, because it describes where your body stores fat, not just how much of it you carry.

Research has repeatedly shown that fat stored around the abdomen carries a higher cardiometabolic risk than fat stored around the hips and thighs. A DEXA scan measures both regions directly, with millimetre-level precision, and the ratio between the two is a practical way to summarise your risk pattern. This guide explains what the A/G ratio is, what counts as a normal or elevated value, why it matters for heart disease risk, and what to do if your result is higher than you would like.

During a DEXA scan, the software divides the body into defined regions. The android region is a box drawn across the abdomen, roughly from the top of the pelvis up to a point below the chest. The gynoid region is drawn across the hips and upper thighs. Fat mass is measured inside each box separately.

The android to gynoid fat ratio is a simple division. You take the fat mass inside the android box and divide it by the fat mass inside the gynoid box. The figure that comes out is a number without units, usually somewhere between about 0.4 and 1.4.

The value matters because abdominal fat is metabolically very different from hip and thigh fat. Fat stored around the abdomen includes a significant amount of visceral adipose tissue, which sits between the internal organs and secretes inflammatory messengers that drive insulin resistance and arterial damage. Fat stored on the hips and thighs is largely subcutaneous and behaves in a more metabolically neutral way. According to the British Heart Foundation, where you carry excess weight is a meaningful part of your overall cardiovascular risk, not just how much you carry (British Heart Foundation, 2023).

There is no universally agreed cut-off, but reference values published in peer reviewed body composition research give a useful guide. A commonly cited threshold study by Aucouturier and colleagues, published in the journal Obesity, found that an A/G ratio above roughly 1.0 in men and 0.8 in women was associated with a clearly increased risk of cardiometabolic features such as raised triglycerides, lower HDL cholesterol and higher fasting glucose (Aucouturier et al., Obesity, 2009).

A reasonable working framework:

• Low risk: A/G below 0.8 in women and below 1.0 in men.
• Borderline: 0.8 to 0.9 in women and 1.0 to 1.1 in men.
• Elevated risk: above 0.9 in women and above 1.1 in men.

These are population averages and your clinician will always interpret the number in the context of your overall health, blood pressure, cholesterol, blood sugar and family history. A lean person with an otherwise normal profile and a slightly elevated A/G ratio is a very different situation to someone with high A/G combined with raised blood pressure and abnormal lipids.

BMI is a calculation based on height and weight alone. It cannot tell the difference between muscle and fat, and it cannot tell you anything about where fat is stored. Two people with an identical BMI of 28 can have completely different cardiovascular risk depending on whether their excess weight is muscle, hip fat or abdominal fat.

A 2020 meta-analysis in the Journal of the American College of Cardiology concluded that measures of central adiposity, including DEXA derived trunk and android fat, were more strongly associated with incident cardiovascular events than BMI across a wide range of populations (Piche et al., JACC, 2020). In other words, knowing your A/G ratio adds useful information on top of simply knowing your weight.

This is one of the reasons a body composition DEXA scan is so valuable in routine health screening. It reveals risk patterns that the bathroom scale and a BMI chart cannot pick up.

An elevated A/G ratio typically reflects a higher proportion of android fat, much of which is visceral. This pattern is linked to several mechanisms that raise cardiovascular risk:

• Chronic low grade inflammation, driven by cytokines secreted by visceral adipose tissue.
• Insulin resistance, which is a central feature of metabolic syndrome and a strong predictor of type 2 diabetes.
• Dyslipidaemia, typically raised triglycerides and lower HDL cholesterol.
• Raised blood pressure, partly through effects on the renin angiotensin system.

The NHS notes that fat stored around the waist is particularly associated with heart disease, stroke and type 2 diabetes, and that reducing central fat through weight loss can improve blood pressure, cholesterol and glucose control (NHS, Why body shape matters, 2024).

Almost anyone can benefit from knowing their A/G ratio, but it becomes particularly informative in the following situations:

• Adults over 40, especially around the menopause, when fat distribution tends to shift toward the abdomen.
• Anyone with a family history of type 2 diabetes, heart disease or stroke.
• People with polycystic ovary syndrome, where android fat accumulation is common.
• Patients being assessed for or already taking GLP-1 or GIP-based weight loss medication.
• Athletes who want a deeper understanding of their body composition beyond total weight.

If you would like to understand the scan itself in more detail before booking, you can learn more about how DEXA scanning works.

The good news is that android fat, the component driving a high A/G ratio, is generally the first type of fat to fall in response to sustained lifestyle changes. Evidence based strategies include:

• Sustained, moderate calorie deficit built around whole foods and adequate protein. Resistance training protects lean mass, so the fat you lose comes disproportionately from the android region.
• Regular aerobic exercise, particularly moderate to vigorous activity, which directly reduces visceral fat even when overall weight does not change dramatically (Journal of Clinical Endocrinology & Metabolism, Vissers et al., 2013).
• Resistance training two to three times per week, which helps maintain or build muscle mass and supports insulin sensitivity.
• Sleep and stress management, as short sleep and chronically raised cortisol both favour central fat storage.
• Medical review of blood pressure, lipids and glucose alongside lifestyle changes, so that cardiometabolic risk is managed as a whole, not just on the scan.

For readers who want to dig deeper into the DEXA numbers behind all of this, our guide to healthy body fat percentage and why a DEXA scan is the gold standard walks through the broader picture of fat mass, lean mass and how a clinician interprets the full report.

If your A/G ratio is persistently elevated and lifestyle changes alone have not been enough, it is worth having a conversation with a doctor about supervised medical weight loss. GLP-1 and GIP receptor agonists such as tirzepatide and semaglutide have been shown in randomised trials to produce meaningful reductions in visceral and android fat, not just total body weight (Ryan et al., New England Journal of Medicine, 2022).

Is the A/G ratio the same as the waist to hip ratio?

No. The waist to hip ratio is based on tape measurements of circumference. The A/G ratio from a DEXA scan measures actual fat mass in defined anatomical regions, which is much more precise and is not confounded by muscle or bone.

Can a lean person still have a high A/G ratio?

Yes. This is sometimes described as thin on the outside, fat on the inside, and it is an important reason why DEXA scanning can reveal risk that is invisible on the scale or in the mirror.

How often should I repeat a DEXA scan to track my A/G ratio?

For most adults making lifestyle changes, every six to twelve months is sensible. During active treatment with weight loss medication, your clinician may recommend a repeat scan at three to six months to confirm that fat loss is coming from the right compartments and that lean mass is being preserved.

Does a low A/G ratio mean I have no cardiovascular risk?

No. A healthy A/G ratio is reassuring, but it is only one input. Blood pressure, lipids, blood sugar, smoking status, family history and fitness all matter and should be reviewed together.

Is a DEXA scan safe enough to repeat regularly?

Yes. The radiation dose from a body composition DEXA scan is very low, typically a small fraction of the daily background radiation in the UK, which is why it is suitable for serial monitoring.

If you would like a precise, clinician reviewed picture of your android to gynoid fat ratio and the rest of your body composition, you can book a scan at our central London clinic. Appointments typically last around twenty minutes and you will receive a full report explaining your numbers in plain English.

Call 0207 637 8227 or book online through our Harley Street clinic page. A bone density DEXA scan can be added to the same visit if you also want to review your skeletal health in detail.

Reviewed by Dr Emil Gadimali, DEXA London.