Conditions · Systemic conditions
Metabolic syndrome !
Metabolic syndrome is a cluster of risk factors (belly fat, high blood pressure, blood sugar and triglycerides, low HDL) that raises diabetes and heart risk.
Updated 2026-10-30
Structures involved
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- Greater omentum
- Liver
- Pancreas
- Abdominal aorta
- Kidneys
- LAD (anterior descending artery)
- Right coronary artery
- Left ventricle
In biochemistry
- CETP (cholesteryl ester transfer protein)
- VLDL (very-low-density lipoprotein)
- HDL (high-density lipoprotein)
- Gamma-glutamyl transferase (GGT) as a lab test
- Acetyl-CoA carboxylase (ACC)
- Malonyl-CoA
- Macronutrients and the energy value of food
- Balanced diet
- Insulin signalling
- Leptin, appetite and obesity
- AMP-activated protein kinase (AMPK)
- Insulin receptor
In histology
In the clinical exam
In physiology
- Physiology of hypertension
- Physiology of diabetes and ketoacidosis
- Blood glucose, glucose tolerance test and HbA1c
- Appetite hormones: leptin, ghrelin and incretins
- Energy balance, food intake and obesity
Why it happens
- Obesity: leptin, adipokines and its consequences
- Fatty change (steatosis)
- Islets and insulin: secretion and actions
- Lipoprotein metabolism
What it is
A cluster of linked cardiometabolic risk factors (central obesity, high blood pressure, high fasting glucose, high triglycerides and low HDL cholesterol) that together raise the risk of type 2 diabetes and cardiovascular disease.
Who gets it
Very common in adults worldwide and in Latin America, increasing with age, abdominal obesity and sedentary urban lifestyles. Prevalence estimates differ depending on which definition is used. Among 784 university students in Tunja, Colombia (mean age 20), 8.7% met the harmonised IDF criteria.
Causes
- Central (visceral) obesity
- Insulin resistance
- Genetic predisposition and family history
- Diets high in calories, refined sugar and ultra-processed foods
- Physical inactivity
Risk factors
- Increasing age
- Excess weight with a large waist circumference
- Sedentary lifestyle and poor sleep
- Family history of type 2 diabetes or early cardiovascular disease
- Polycystic ovary syndrome or previous gestational diabetes
- Drugs such as antipsychotics and long-term glucocorticoids
Pathophysiology
Enlarged visceral fat releases free fatty acids and inflammatory adipokines and less adiponectin. This causes insulin resistance in liver and muscle, so the pancreas secretes more insulin. The liver produces more triglyceride-rich VLDL and HDL falls; hyperinsulinaemia, sodium retention and sympathetic activation raise blood pressure, and endothelial dysfunction speeds atherosclerosis.
Classification
- Definitions vary: NCEP ATP III, International Diabetes Federation (IDF) and the 2009 harmonised criteria are the most used
- Harmonised criteria: 3 or more of 5 components (waist, triglycerides, HDL, blood pressure, fasting glucose)
- Commonly used cut-offs: triglycerides ≥150 mg/dL, HDL <40 mg/dL (men) or <50 mg/dL (women), BP ≥130/85 mmHg, fasting glucose ≥100 mg/dL, or treatment for these
- Waist cut-offs differ by definition and population; the IDF requires central obesity as an essential criterion
Symptoms and signs
- Usually no symptoms; found on routine check-ups
- Large waist circumference (abdominal obesity)
- Acanthosis nigricans (dark velvety skin on the neck or armpits)
- Symptoms of associated conditions: snoring and daytime sleepiness, fatigue, thirst and frequent urination if diabetes develops
Diagnosis
- Clinical
- Measurement of waist circumference, weight and BMI, and blood pressure; history of diet, activity, sleep, smoking and family history; look for acanthosis nigricans. The definition used should be stated.
- Tests
- Fasting glucose (and HbA1c or a glucose tolerance test if borderline), lipid profile (triglycerides, HDL, LDL), liver enzymes for fatty liver, creatinine and urine albumin. Cardiovascular risk calculation.
- Imaging
- Not needed for diagnosis; liver ultrasound if fatty liver is suspected.
Differential diagnosis
- Cushing syndrome
- Hypothyroidism
- Polycystic ovary syndrome
- Familial dyslipidaemias
- Drug-induced weight gain and dyslipidaemia (e.g. antipsychotics, glucocorticoids)
Goal of treatment
Reduce the long-term risk of type 2 diabetes and cardiovascular disease by reducing abdominal fat and insulin resistance and controlling each risk factor.
Treatment
- Lifestyle
- First-line: modest sustained weight loss, a healthy eating pattern (e.g. Mediterranean-style), regular aerobic and resistance exercise, better sleep and stopping smoking.
- Medical
- Treatment of each component when needed: statins for dyslipidaemia, antihypertensives (often ACE inhibitors or ARBs) and metformin for some people with prediabetes.
- Medical
- Anti-obesity drugs, such as GLP-1 receptor agonists, in selected patients with obesity according to guidelines.
- Surgical
- Bariatric (metabolic) surgery for severe obesity with comorbidities when other measures have not worked.
- Follow-up
- Regular checks of weight, waist, blood pressure, glucose and lipids, and periodic cardiovascular risk assessment.
Drugs for this condition
Complications
- Type 2 diabetes
- Coronary heart disease, myocardial infarction and stroke
- Metabolic dysfunction-associated steatotic liver disease (fatty liver), which can progress to cirrhosis
- Chronic kidney disease
- Obstructive sleep apnoea
- Gout and polycystic ovary syndrome
Prognosis
It roughly doubles cardiovascular risk and greatly raises the risk of type 2 diabetes, but it is largely reversible: weight loss and physical activity can improve or remove the components.
Prevention
- Healthy eating and limiting sugary drinks and ultra-processed food
- At least moderate regular physical activity and less sitting time
- Keeping a healthy weight and waist circumference
- Periodic measurement of blood pressure, glucose and lipids in adults
Test yourself
Think of the answer, then tap the question to see it.
What are the five components of metabolic syndrome?
Central obesity (waist), high triglycerides, low HDL cholesterol, high blood pressure and high fasting glucose.
How many components are needed under the 2009 harmonised criteria?
Three or more of the five; the IDF definition instead requires central obesity plus two others.
What is the central pathophysiological mechanism of metabolic syndrome?
Insulin resistance driven mainly by excess visceral fat.
What is the first-line treatment for metabolic syndrome?
Lifestyle change: weight loss, healthy diet and regular physical activity; drugs are added to control individual components.
Which liver disease is closely associated with metabolic syndrome?
Metabolic dysfunction-associated steatotic liver disease (fatty liver), which can progress to steatohepatitis and cirrhosis.
Related conditions
- Type 2 diabetes mellitus
- Arterial hypertension
- Obesity
- Myocardial Infarction (Heart Attack)
- Cushing syndrome
- Hypothyroidism
- Polycystic ovary syndrome
Educational information, not medical advice. For any symptom, see a health professional.
Sources: Metabolic Syndrome (StatPearls (NCBI Bookshelf), 2024); Active commuting to and from university, obesity and metabolic syndrome among Colombian university students (BMC public health, 2018) · adapted, CC BY 4.0.
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Representative model, for educational purposes only.
