📚 Part of our Heart Health Guide — an evidence-based guide.
Most people can tell you roughly what their cholesterol is. Far fewer know their triglycerides, and fewer still know that this is the number on the panel that responds fastest to what they do — often within weeks.
What triglycerides are
Triglycerides are the main storage form of fat. When you eat more energy than you immediately need — from any source, not just fat — your body packages the excess as triglycerides, stores it in fat cells, and circulates the rest in the bloodstream.
That origin explains their behaviour. Because excess carbohydrate and alcohol are converted to triglycerides by the liver, they respond strongly to sugar and drinking, which surprises people who assume a fat number must be about dietary fat.
The ranges
- Normal: below 150 mg/dL
- Borderline high: 150–199
- High: 200–499
- Very high: 500 or above
The 500 threshold is different in kind from the others. Above it, and particularly above 1,000, the risk is acute pancreatitis — a medical emergency, not a long-term risk statistic. Very high triglycerides need prompt medical attention rather than a lifestyle plan.
Why they matter for your heart
High triglycerides travel in particles that can contribute to plaque, and they rarely arrive alone. The characteristic pattern is high triglycerides with low HDL, and it is one of the clearest signatures of insulin resistance available on an ordinary blood test.
This is why triglycerides appear as one of the five criteria in metabolic syndrome, with the threshold at 150. Read alongside your waist, blood pressure, HDL and fasting glucose, the number is telling you something about your metabolism as a whole, not just your arteries.
A useful free calculation: the triglyceride-to-HDL ratio. It requires no extra test and is a reasonable proxy for insulin resistance.
What raises them
Alcohol. Frequently the single largest contributor, and the one most often overlooked. The liver prioritises metabolising alcohol and produces triglycerides in the process. In some people, even moderate regular drinking keeps the number elevated on its own.
Added sugar and refined carbohydrate, particularly fructose from sweetened drinks, which the liver handles directly.
Excess weight, especially visceral fat.
Uncontrolled diabetes and insulin resistance.
Certain medications — some diuretics, beta blockers, corticosteroids, oestrogens, and some HIV medications.
Hypothyroidism and kidney disease.
Genetics. Familial hypertriglyceridaemia exists, and some people run high despite doing everything right.
How to lower them, in order of impact
Triglycerides are the most responsive lipid marker there is, and the effects show up fast.
1. Cut or stop alcohol. If your triglycerides are high and you drink regularly, start here. A few weeks off can produce a dramatic change, and it is the most common reason a number falls unexpectedly.
2. Cut added sugar and sweetened drinks. This is the dietary lever with the largest effect — larger than cutting dietary fat, which is counterintuitive but consistent (where the sugar is).
3. Lose modest excess weight. Even 5 to 10% often produces a meaningful fall.
4. Move regularly. Aerobic activity lowers triglycerides more reliably than it lowers LDL (how much you need).
5. Eat oily fish. Marine omega-3s genuinely lower triglycerides, and this is one of the few claims for fish oil that holds up well — though supplements do far less for other cardiovascular outcomes than their sales suggest (the honest read). High-dose prescription formulations for very high triglycerides are a different matter and a medical decision.
The broader protocol is in how to lower cholesterol naturally.
Fasting, and why your number may have looked odd
Triglycerides rise substantially after eating — more than any other lipid measure. Non-fasting panels are now considered acceptable for routine screening, but if your triglycerides came back unexpectedly high on a non-fasting sample, that alone may explain it. A repeat fasting test settles it, and is usually preferred when the number is high or when treatment decisions depend on it.
When to see a doctor
Contact your doctor promptly for triglycerides of 500 or above, and urgently for 1,000 or above or for severe abdominal pain with high triglycerides — that combination suggests pancreatitis.
Book a routine appointment for anything above 150, particularly alongside low HDL, an increased waist, high blood pressure or elevated fasting glucose. Ask about non-HDL cholesterol or ApoB if your triglycerides are high — standard calculated LDL becomes unreliable in that situation, which is a technical detail with real consequences for how your risk is judged (the full panel explained).
The honest bottom line
Triglycerides are the lipid number that moves fastest and gets ignored most. Alcohol and added sugar drive them more than dietary fat does, and cutting either can change the number within weeks. Above 150 they are worth acting on; above 500 they are a medical matter because of pancreatitis risk. And high triglycerides with low HDL is not just a lipid problem — it is one of the clearest signs of insulin resistance you can read off an ordinary blood test.
To find out whether atherosclerosis is actually present rather than estimated, see how to read a coronary calcium score.
Frequently asked questions
What is a normal triglyceride level?
A normal fasting triglyceride level is under 150 mg/dL. 150-199 is borderline high, 200-499 is high, and 500 or above is very high and needs medical attention.
How do I lower triglycerides naturally?
Cut back on added sugar, refined carbohydrates, and alcohol; lose excess weight; exercise regularly; and eat more fiber and omega-3-rich fish. These steps can lower triglycerides substantially.
Are triglycerides as important as LDL cholesterol?
LDL is still the primary target, but research increasingly recognizes high triglycerides as an independent contributor to cardiovascular risk that shouldn't be ignored.