Abdominal and visceral fat: why its location matters

What is the difference between abdominal fat and visceral fat?

Abdominal fat is all the fat that builds up in the belly area, and it has two layers. The subcutaneous layer lies just under the skin, and it is the one you can pinch. Visceral fat lies deeper, behind the abdominal muscles, surrounding the liver, the intestine and other organs.

It cannot be seen or pinched, and it is the one that worries us most [1].

What is android and gynoid obesity?

The android distribution is apple-shaped, with fat mainly in the abdomen and trunk; the gynoid distribution is pear-shaped, with fat on the hips and thighs. Both describe where more fat builds up, but the silhouette does not tell you how much visceral fat there is. Waist circumference adds information beyond weight [1].

In women, during the transition to menopause, subcutaneous and visceral abdominal fat can increase [4]. If you notice a change in your waist that you cannot explain, talk to your doctor about it. Diet and physical activity can also change at this stage.

Why does visceral fat increase metabolic risk?

Some of the fatty acids and glycerol released by visceral fat reach the liver through the portal vein. It is one of the proposed mechanisms that explain its association with triglycerides and insulin resistance [1].

Inflammation and high blood pressure are studied through different pathways; they are not proven consequences of a single portal mechanism [1].

Hence its link with type 2 diabetes, hypertension, abnormal cholesterol levels, fatty liver and cardiovascular disease [1]. An international group of experts on visceral obesity proposes measuring the waist at every medical consultation, as an additional vital sign [5].

It provides information that body mass index (BMI) does not, and two people with the same BMI can have different waists and risks [5].

None of this is a life sentence. It helps you know where to focus.

How do I know if I have too much abdominal fat?

Imaging tests, such as magnetic resonance imaging, can assess visceral fat [1]. A tape measure gives the waist circumference: it provides information about central adiposity, but does not measure fat between the organs directly [2].

How to measure your waist. Stand up, relaxed and with nothing tight around the area. Find the lower edge of the last rib and the top of the hip. Wrap the tape around the abdomen halfway between the two points and keep it horizontal, without pulling it tight [6].

NICE places that point just above the navel and asks you to breathe out normally before reading the figure [2].

Waist circumference. It adds information to weight, but on its own it does not diagnose visceral fat or a disease [5]. The WHO 2011 report collects historical examples of cut-off points; it did not set a universal threshold or recommend applying them to everyone [6].

The waist-to-height ratio. It is the easiest figure to remember and works the same for men and women. Divide your waist by your height, both in centimetres. The British obesity guideline (NICE) considers a result between 0.4 and 0.49 healthy, 0.5 to 0.59 increased risk, and 0.6 or above high risk [2].

Its message fits in one sentence: your waist should measure less than half your height [2]. If you are 165 cm tall, the aim is a waist below 82.5 cm. It is mainly proposed for people with a BMI below 35 [2].

And the waist-to-hip ratio? It is calculated by dividing the waist by the hip, measured at the widest part of the buttocks. It is another way of describing fat distribution, but it needs two measurements. The NICE guideline uses the waist-to-height ratio, together with BMI, to guide the assessment [2].

None of these figures is a diagnosis. They are a starting point for talking to your doctor or dietitian-nutritionist, and they are read alongside BMI, blood tests and your history. If you want to see how they fit with weight, we explain it in underweight, healthy weight, overweight and obesity.

Can you reduce belly fat by doing sit-ups?

One analysis of thirteen studies found no localised fat reduction from training a specific muscle [3]. Sit-ups should not be presented as a way to remove fat from the belly alone.

Sit-ups strengthen the trunk muscles. That analysis did not measure visceral fat or study belly bands, gels or infusions [3]. None of these products should be presented as a treatment to reduce visceral fat.

What reduces visceral fat?

A review of 40 trials in adults with overweight or obesity examined exercise and calorie restriction; 36 trials contributed data to the pooled analysis. Both were associated with less visceral fat measured by imaging. The dose-response relationship was seen for the energy deficit produced by exercise, not for eating fewer calories [7] .

A moderate deficit means eating slightly less than you burn, so that you can keep it up for months. The plate is based on vegetables, pulses, wholegrain cereal, enough protein and olive oil. You will find it step by step in our guide to diet and weight loss.

Movement can be part of the plan. The WHO recommends that adults do muscle-strengthening activities for the major muscle groups at least two days a week [8] . That recommendation is for general health and does not promise to reduce fat in one specific area.

If you also have obesity, hypertension, diabetes or fatty liver, the plan is adjusted to your case and coordinated with your doctor. The guide to obesity and diet gives you the full framework.

What is worth reviewing about weight and abdominal fat in men?

The waist-to-height ratio uses the same cut-offs in adult men and women with a BMI under 35 [2]. So you do not need a different target just because you are a man. The figure is assessed together with weight and risk factors, without inferring a diagnosis from body shape [2].

What the waist does not tell you on its own

The tape measure gives an indication of central adiposity, but on its own it does not measure how much visceral tissue there is or explain why the waist is growing. Discuss the measurement with your doctor together with BMI and other risk factors [2][5].

Training one muscle does not reduce the fat directly above it [3]. Assessing possible fatty liver requires a medical evaluation; the waist, on its own, does not confirm that diagnosis.

What we see in consultation

There are three common pitfalls that we see in clinical practice.

• Looking only at the scales. Your waist can come down even when your weight barely moves, both with exercise and with changes to your diet [5]. In consultation we can review your weight together with your waist and other data, without interpreting a single measurement in isolation.
• Measuring in a different place each time. One day above the navel, another day lower, another after eating. Changing the measuring point makes the figures hard to compare [5]. Always measure between the rib and the hip, at the same time of day.
• Cutting back too much too quickly. If you have started skipping dinners or eating very little, bring that pattern to consultation before cutting back further. We can look at how to organise your meals without resorting to extreme restriction.