High blood triglycerides, known medically as hypertriglyceridemia, means there is too much of a particular type of fat in the blood, which at mild levels adds to the risk of heart and blood vessel disease and at very high levels can cause sudden inflammation of the pancreas [2].
This page provides general information. It does not replace advice from a doctor or another qualified healthcare professional.
Triglycerides are the main type of fat in the blood and the body’s main store of energy. Some come from food, and the liver makes the rest [6]. Hypertriglyceridemia is the medical name for having too much.
How this differs from high cholesterol. Both are fats and both appear on the same blood test, though they are not the same thing. Cholesterol builds cell walls and makes hormones. Triglycerides are stored fuel. They have different causes and different treatments, which is why this page covers triglycerides alone. For the wider picture, see the trialport guide to dyslipidemia.
The severity levels. The Endocrine Society sorts fasting results into bands, since a slightly raised level and an extremely high one are different problems [2]:
| Band | mg/dL | mmol/L |
|---|---|---|
| Normal | below 150 | below 1.7 |
| Mild | 150 to 199 | 1.7 to 2.3 |
| Moderate | 200 to 999 | 2.3 to 11.2 |
| Severe | 1,000 to 1,999 | 11.2 to 22.4 |
| Very severe | 2,000 or more | 22.4 or more |
Mild and moderate levels matter mainly for the heart and blood vessels, severe and very severe levels for the risk of pancreatitis [2]. Other organizations differ: several treat 500 mg/dL and above as severe, and United Kingdom guidance uses mmol/L [3,12,5].
Raised triglycerides are common. About one quarter of United States adults aged 20 and over had a level of 150 mg/dL or more in a national survey covering 2009 to 2012 [1]. That counts people tested in a survey, not people given a diagnosis. Raised levels affect 10 to 20 percent of United States children and adolescents [9].
Severe levels are far less common. A 2025 review pooling studies from several countries found roughly 1 in 88 adults above 500 mg/dL and 1 in 556 above 1,000 mg/dL, higher in the United States and China than in Europe. Guidelines disagree about where severe begins, and good data are missing for most of the world [15]. Familial chylomicronemia syndrome has been estimated at about 1 in 300,000, and far higher in parts of Quebec, though estimates vary [11,10].
Levels rise when the body makes more triglycerides than it clears [6].
Inherited causes. A gene is an instruction inside a cell, and a gene variant is a change in that instruction. Familial chylomicronemia syndrome is the severe genetic form, caused by changes in both copies of LPL, APOC2, APOA5, LMF1 or GPIHBP1. That pattern is called autosomal recessive: a person needs a changed copy from each parent, and carrier parents usually have no symptoms. Multifactorial chylomicronemia syndrome is much more common, where small inherited susceptibilities combine with a trigger such as diabetes, alcohol or a medicine [11]. Familial combined hyperlipidemia raises triglycerides too [2]. Treatment differs, so telling these apart is important [3].
Other causes. These include uncontrolled diabetes, chronic kidney disease, an under-active thyroid, liver disease, pregnancy and metabolic syndrome [2,6]. Alcohol raises triglycerides, and some people are sensitive to small amounts [6]. So do several prescribed medicines, including some diuretics, beta blockers, steroids, oral estrogen and isotretinoin [2,3]. Never stop one on your own. Ask the prescriber.
Mild and moderately raised triglycerides usually cause no symptoms, and turn up on a blood test done for another reason [1,6].
Very high levels can cause visible signs [10,11]:
Difficulties with mood, memory and thinking are reported in the familial form. That form shows early in children, about a quarter before their first birthday. Pregnancy raises triglycerides and, in the familial form, the risk of pancreatitis, so it is monitored closely [11].
When to seek urgent help. Very high triglycerides can trigger acute pancreatitis, which needs hospital treatment. Ask for an urgent doctor’s appointment, or contact your local urgent care service, if you get sudden severe tummy pain that does not go away, especially with a high temperature or shivering. Call emergency services or go to an emergency department if that pain spreads to your back, or comes with lasting bloating, a fast heartbeat, difficulty breathing, or bruised-looking skin around the belly button [7].
Triglycerides are measured with a simple blood test, usually part of a lipid panel that also reports cholesterol [6]. Most people start with a family doctor, and move to a specialist lipid clinic where levels are very high or a genetic cause is suspected [5].
Fasting or not. The Endocrine Society recommends a fasting sample, after 12 hours, for making the diagnosis [2]. United Kingdom guidance no longer requires fasting for routine testing, and HEART UK suggests aiming below 2.0 mmol/L non-fasting or 1.7 mmol/L fasting [6]. Above 1,000 mg/dL a fasting sample is not needed [11]. So it is often fasting, not always, and the team will say which they want. Two results weeks apart are advised before starting a triglyceride medicine [3].
The next step is looking for a cause: blood sugar, thyroid, kidney and liver tests, a review of current medicines, and questions about alcohol [2]. Genetic testing can confirm the familial form [11]. Diagnosis is often delayed, since mild and moderate levels cause nothing a person would notice, and the familial form is repeatedly mistaken for unexplained pancreatitis [11]. English guidance asks for specialist advice above 10 mmol/L and urgent review above 20 mmol/L [5].
The goal differs by level: reducing heart and blood vessel risk at mild and moderate levels, and preventing pancreatitis at severe levels. The first step is treating the cause, whether that is blood sugar, an under-active thyroid, kidney or liver disease, or a medicine [2].
Food, alcohol and activity. Guidelines call these the foundation of care, with a registered dietitian giving individual advice rather than general rules. Alcohol is limited, and stopped where levels are markedly raised. Activity is encouraged, and weight is discussed with the care team [3]. Where levels are severe a strict low-fat plan is prescribed and monitored, with total fat often kept to 20 grams a day or less [11]. None of this is anyone’s fault.
Fibrates. Where there is a risk of triglyceride-related pancreatitis, a fibrate such as fenofibrate is the recommended first medicine [2].
Prescription omega-3. These are not shop-bought fish oil, and supplements are no substitute. One purified form, icosapent ethyl, cut major cardiovascular events by 25 percent in the REDUCE-IT trial, with more atrial fibrillation and bleeding than placebo [3].
Statins. Statins mainly lower cholesterol and remain the foundation of treatment for heart and blood vessel risk where triglycerides stay high. They lower triglycerides only modestly and are not used alone for severe levels [1,2,8].
Newer targeted medicines. Volanesorsen is authorized in Europe, though not in the United States, for genetically confirmed familial chylomicronemia syndrome [4]. Olezarsen, a monthly injection, was approved in the United States in December 2024 for that condition, and in June 2026 for severe hypertriglyceridemia to lower the risk of acute pancreatitis [12]. Plozasiran, given every three months, was approved there in November 2025 for the familial form [13]. There is no cure, and availability differs greatly between countries.
For most people this is a number followed over years alongside blood pressure and cholesterol. Where levels are severe, monitoring is closer, and in the lipoprotein lipase form fasting triglycerides are usually checked every three months. Several things are worth discussing in advance in that form, including alcohol, oral estrogen, diuretics, isotretinoin, steroids, beta blockers and fish oil supplements. Bring that list to whoever prescribes. Close relatives are advised to have a lipid blood test, and family planning is a conversation to have early [11].
An emergency plan helps: know the warning signs of pancreatitis, keep a written note of the diagnosis and current medicines, and agree who to call out of hours. The toll of repeated hospital visits and a strict eating plan is recognized in the severe forms rather than imagined [11].
Clinical trials test whether a treatment works and is safe. Triglycerides are an active research area, so studies come up reasonably often. Deciding whether to look into one is personal, and it helps to take it in steps.
It is worth being clear on what a study involves:
Every trial has rules about who can take part, called eligibility criteria. For a triglyceride study, they might include a fasting level inside a set range confirmed on two samples weeks apart, a stable statin dose beforehand, blood sugar under reasonable control, no recent acute pancreatitis, a genetic result or clinical score confirming familial chylomicronemia syndrome, and reliable contraception for some medicines.
trialport’s medifit helps people consider information related to possible medical suitability. It does not diagnose a condition, confirm eligibility or replace formal screening by the study team.
Explore high blood triglycerides clinical trials through trialport
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Most recent movement has come from medicines that switch off a single gene’s message in the liver.
Study status checked: 3 August 2026. Research moves quickly and what is studied changes, so this list will date. For current information, search at app.trialport.com.
In the United Kingdom, HEART UK is the national cholesterol and blood fats charity, with a clear triglycerides section on causes, targets and treatment [6]. The NHS page on acute pancreatitis sets out the warning signs [7].
In the United States, the National Lipid Association’s patient site LearnYourLipids explains triglycerides and testing plainly, and can help locate a lipid specialist [16]. The FCS Foundation is the organization for familial chylomicronemia syndrome, run for and with affected families [17].
Coverage elsewhere is thin. Most countries have a general heart charity rather than anything specific to triglycerides, and there is little material in languages other than English. Where no local group exists, a national heart or lipid association, or the treating clinic, is the best starting point.
Is a high triglyceride result serious?
It depends how high. Mild and moderate levels add to long-term heart risk without symptoms. Levels above roughly 500 mg/dL bring a risk of pancreatitis [2,3].
Are triglycerides the same as cholesterol?
No. Both are fats measured on the same blood test, though they do different jobs and are treated differently [6].
Do I need to fast before the test?
Often, though not always. A fasting sample is preferred for the diagnosis, while United Kingdom guidance no longer requires fasting for routine testing. Follow whatever your clinic asks [2,5,6].
Can high triglycerides be inherited?
Yes. The severe familial form needs a changed copy of the same gene from each parent, and relatives are advised to be tested [2,11].
Do fish oil capsules from a shop help?
Guidelines advise prescription-strength omega-3 instead, and in the lipoprotein lipase form supplements are avoided because they can raise levels [3,11].
Written by: trialport editorial team
Reviewed by: Keith Berelowitz, Founder and CEO, trialport
Reviewed on: 3 August 2026
Next review due: 3 August 2027
References last checked: 3 August 2026