A lipid panel — sometimes called a lipid profile or cholesterol test — is one of the most commonly ordered blood tests in routine healthcare. It measures the fats circulating in your bloodstream and is used to assess your risk of cardiovascular disease, including heart attack and stroke.
Despite being so common, the results confuse many patients. The numbers come with units, reference ranges, and a vocabulary that isn't self-explanatory. This guide breaks down everything on a standard lipid panel report.
A lipid panel is a blood test that measures the types and amounts of fat circulating in your bloodstream. It reports total cholesterol, LDL (low-density lipoprotein), HDL (high-density lipoprotein) and triglycerides — the four values clinicians use to assess cardiovascular risk and guide decisions about lifestyle changes or medication.
The four main measurements
A standard lipid panel reports four values. All are measured in millimoles per litre (mmol/L) in most countries, or milligrams per decilitre (mg/dL) in the United States.
- **Total cholesterol** — the combined measure of all cholesterol types in your blood. A useful starting point but not the most informative figure on its own.
- **LDL cholesterol (low-density lipoprotein)** — often called 'bad' cholesterol. LDL carries cholesterol from the liver into the bloodstream; elevated levels are associated with the build-up of plaque in artery walls (atherosclerosis), which increases heart attack and stroke risk.
- **HDL cholesterol (high-density lipoprotein)** — often called 'good' cholesterol. HDL carries cholesterol away from the arteries and back to the liver for removal. Higher HDL is protective; low HDL is a risk factor independent of LDL.
- **Triglycerides** — a type of fat stored in your cells and circulating in your blood. High triglycerides, particularly combined with low HDL, increase cardiovascular risk. Triglycerides are especially sensitive to diet, alcohol intake and physical activity.
What the numbers mean: reference ranges
Target values differ based on your individual cardiovascular risk profile. Someone who has already had a heart attack has more aggressive LDL targets than a healthy 30-year-old with no risk factors. The ranges below are general adult guidelines.
- **Total cholesterol:** ideally below 5.0 mmol/L (193 mg/dL); above 6.2 mmol/L (240 mg/dL) is high
- **LDL cholesterol:** ideally below 3.0 mmol/L (116 mg/dL) for low-risk individuals; below 1.8 mmol/L (70 mg/dL) for those with established cardiovascular disease
- **HDL cholesterol:** protective above 1.0 mmol/L (39 mg/dL) for men and 1.2 mmol/L (46 mg/dL) for women; above 1.5 mmol/L (58 mg/dL) is considered cardioprotective
- **Triglycerides:** normal below 1.7 mmol/L (150 mg/dL); borderline high 1.7–5.6 mmol/L; above 5.6 mmol/L raises risk of pancreatitis
The cholesterol ratio: a useful extra calculation
Some reports include the total cholesterol to HDL ratio (TC:HDL). This is calculated by dividing your total cholesterol by your HDL cholesterol. A ratio below 4 is generally considered healthy; a ratio above 6 indicates elevated risk. This single figure captures both the harmful and protective sides of cholesterol in one number.
Non-HDL cholesterol: the overlooked figure
Non-HDL cholesterol is your total cholesterol minus your HDL. It captures all the potentially atherogenic (artery-damaging) particles in one number and is increasingly preferred over LDL alone, particularly in people with high triglycerides. Some guidelines set a non-HDL target of less than 3.4 mmol/L (130 mg/dL) for high-risk individuals.
What raises LDL — and what lowers it
LDL cholesterol is influenced by both genetic factors and lifestyle. Understanding the levers you can act on helps make the numbers feel less fixed.
- **Diet** — saturated and trans fats raise LDL; replacing them with unsaturated fats (olive oil, nuts, oily fish) reduces it
- **Soluble fibre** — oats, legumes, apples and flaxseed bind cholesterol in the gut and reduce absorption
- **Physical activity** — regular aerobic exercise raises HDL and lowers triglycerides; the effect on LDL is modest but consistent
- **Weight** — losing even 5–10% of body weight can meaningfully improve the full lipid profile
- **Alcohol** — heavy drinking raises triglycerides significantly; moderate drinking modestly raises HDL
- **Smoking** — lowers HDL; quitting consistently improves the lipid profile
- **Statins and other medications** — if lifestyle changes are insufficient, medications can reduce LDL by 30–60%
Familial hypercholesterolaemia: when the genes matter more
About 1 in 250 people have familial hypercholesterolaemia (FH) — a genetic condition that causes LDL levels to be elevated from birth, regardless of diet. FH is significantly under-diagnosed. If your LDL is very high despite a healthy lifestyle, or if there is a strong family history of early heart disease, ask your doctor whether genetic testing is appropriate.
"I tell every patient: LDL and HDL are not good or bad in isolation. What matters is the trajectory over time, and whether we're moving in the right direction together."
Dr. Lina Haddad, CMO, Looms
Why fasting matters for your test
Most lipid panels are measured after a 9–12 hour fast because triglycerides are directly affected by recent meals. A non-fasting triglyceride is consistently higher than a fasting one, which can distort the calculation of LDL (which is often derived rather than directly measured). If your results seem unexpectedly high, check whether you fasted correctly before the test.
Tracking trends over time
A single lipid panel reading matters less than the pattern across multiple tests. Looms' lab insights feature charts your cholesterol values over time automatically, so you and your doctor can assess whether lifestyle changes or medications are having the intended effect — and spot any concerning drift before it becomes urgent.