What is fatty liver (NAFLD)?
Fatty liver means fat has accumulated inside liver cells, exceeding roughly 5% of the liver's weight. When this isn't linked to alcohol use, it's called non-alcoholic fatty liver disease (NAFLD) — by far the most common cause of a "bright liver" seen on routine abdominal ultrasound. It's usually associated with diet, sedentary lifestyle, central obesity, insulin resistance, diabetes, or high cholesterol.
Fatty liver is remarkably common in India. Research reviews estimate that roughly 9 to 32% of the general adult population is affected, with meta-analyses suggesting the true figure may be closer to one in three adults — and rates are considerably higher in people who are overweight, diabetic, or have high blood pressure. Diet high in refined carbohydrates, low physical activity, and rising obesity and diabetes rates are the major drivers in Indian cities.
How ultrasound grades fatty liver
On ultrasound, a healthy liver and kidney appear similarly bright (echogenic). As fat builds up inside liver cells, the liver becomes progressively brighter than the kidney, and it becomes harder to see structures behind it — the walls of the portal vein and, eventually, the diaphragm. Radiologists use this pattern to assign a grade from 0 (normal) to 3 (severe).
Grade 1 — Mild
- Liver mildly brighter than the kidney
- Portal vein walls and diaphragm still clearly visible
- Often found incidentally, usually no symptoms
Grade 2 — Moderate
- Liver noticeably brighter than the kidney
- Portal vein walls become difficult to see
- Often accompanies insulin resistance or high triglycerides
Grade 3 — Severe
- Liver markedly bright, deep structures poorly seen
- Diaphragm outline barely visible; posterior shadowing
- Carries higher risk of progressing to NASH and fibrosis
What each grade means for you
Grade 1: usually reversible
- The earliest, most reversible stage of fatty liver
- Most patients have no symptoms and discover it incidentally
- Sustained diet and lifestyle change can normalise this within months
Grade 2 & 3: needs closer attention
- Grade 2 often signals metabolic strain — check blood sugar, insulin, and lipid profile
- Grade 3 is a medical red flag warranting prompt evaluation for NASH and fibrosis risk
- Your doctor may recommend liver function tests, an HbA1c, a lipid panel, or elastography
Regardless of grade, fatty liver is a signal worth acting on early — it often travels together with other metabolic conditions common in Indian adults, including diabetes and high cholesterol, which are worth screening for at the same time.
Beyond grading: why shear wave elastography matters
Standard greyscale grading tells you roughly how much fat is in the liver — but not whether that fat has begun to cause scarring, or fibrosis. Two people can each have a “Grade 2” fatty liver on their report yet have very different amounts of underlying liver stiffening. Distinguishing simple fat from early fibrosis has traditionally required a liver biopsy.
Shear wave elastography solves this non-invasively. Rather than only judging brightness, it sends a gentle pulse into the liver and measures how fast the resulting “shear waves” travel through the tissue. Because these waves move faster through stiffer tissue, the measured stiffness (reported in kilopascals, kPa) reflects how much fibrosis is present — the loss of elasticity corresponds closely to the degree of liver damage.
Greyscale grading tells you
- Roughly how much fat is in the liver (Grade 1–3)
- A quick, visual, somewhat subjective estimate
- Nothing directly about scarring or fibrosis
Shear wave elastography adds
- A numeric stiffness value (kPa) that reflects fibrosis
- The ability to separate simple fatty liver from early scarring
- Reproducible numbers to track your liver over time — without a biopsy
Who should get a liver ultrasound, and how often
A liver ultrasound is a simple, painless, radiation-free way to check for fatty liver as part of routine or preventive health screening. It's especially worth prioritising if you:
- Are overweight, obese, or carry weight mainly around the abdomen
- Have diabetes, prediabetes, or a strong family history of diabetes
- Have high cholesterol, high triglycerides, or high blood pressure
- Have unexplained fatigue or mildly elevated liver enzymes (SGOT/SGPT) on a blood test
- Are of normal weight but have central fat distribution — lean fatty liver is well documented, particularly in South Asian populations
If a previous scan showed Grade 1 fatty liver, a repeat ultrasound after 6 to 12 months of lifestyle change is a reasonable way to check progress. Grade 2 and 3 findings should be followed up sooner, in consultation with your physician.
Common questions
What is fatty liver (NAFLD)?
Fatty liver, or non-alcoholic fatty liver disease, means fat has built up inside liver cells — usually linked to diet, sedentary lifestyle, obesity, diabetes, or high cholesterol rather than alcohol. It is very common in India, with studies estimating that roughly 9 to 32% of the general adult population is affected.
What do fatty liver Grade 1, 2 and 3 mean?
These grades describe how bright the liver appears on ultrasound compared to the kidney. Grade 1 is mild, Grade 2 is moderate with vessel walls harder to see, and Grade 3 is severe with the diaphragm barely visible. Higher grades generally indicate more fat accumulation.
Is fatty liver reversible?
Grade 1 is usually reversible with sustained diet and lifestyle changes. Grade 2 needs more consistent correction along with monitoring of blood sugar and lipids. Grade 3 needs prompt medical attention but can still improve with treatment.
Can a normal-weight person have fatty liver?
Yes — lean fatty liver is well recognised, particularly in South Asian populations, where central fat distribution can cause fatty liver even at a normal BMI. This is why ultrasound screening is valuable even for patients who don't look overweight.
Does an ultrasound grade confirm liver damage or fibrosis?
No. Ultrasound grading estimates fat content, not scarring. If fibrosis needs assessment, your doctor may recommend blood tests or shear wave elastography for a more precise picture.
What is shear wave elastography, and why does it help?
Shear wave elastography measures liver stiffness by tracking how fast sound-generated shear waves travel through the tissue — stiffer, more fibrotic liver transmits them faster. It gives a numeric stiffness value (in kPa) that helps distinguish simple fatty liver from early fibrosis, non-invasively and without a biopsy. At Nitara Scans it is performed using the Samsung V7's built-in S-Shearwave imaging, so it can be done alongside your abdomen scan in the same visit.
"I had my whole abdomen USG and other scans done by Dr. Nayana. The whole process was so seamless and relaxing. She is really polite and makes you feel comfortable with the procedure. And tells everything patiently."
"The ultrasound service is helpful with right diagnosis. The radiologist explained everything clearly. Staff was professional, procedure smooth, report clear and timely."
Liver & abdomen ultrasound in HSR Layout, Bengaluru
Nitara Scans and Diagnostics offers abdomen ultrasound and the Liver Care Package (abdomen scan with liver elastography) in HSR Layout, Bengaluru. All scans are personally performed by Dr. Nayana N Sunku — DMRD, DNB Radiology, Fetal Medicine Fellow.