Triglycerides: What the Blood Test Shows and Why Athletes Should Care

Triglycerides are often the forgotten line on a cholesterol report. Athletes tend to assume their results will be excellent, and frequently they are — but heavy alcohol use, very high-calorie bulking diets, certain medicines and some performance drugs can push them up. Our editorial team explains what the number means, how to prepare for the test and when a result needs action.

What triglycerides are

Triglycerides are the main form in which the body stores and transports fat. Each molecule consists of three fatty acids attached to glycerol. After a meal, triglycerides from food travel in chylomicrons; between meals, the liver packages them into very-low-density lipoproteins (VLDL) to deliver energy to muscles and fat tissue.

For active people, triglycerides are an important fuel. Muscle cells store their own triglyceride droplets, which are used during endurance exercise. Well-trained athletes are particularly good at breaking down and using circulating triglycerides, which is one reason their blood levels are often low.

Raised blood triglycerides, however, are associated with increased cardiovascular risk, partly because triglyceride-rich lipoproteins and their remnants contribute to atherosclerosis. Very high levels can trigger acute pancreatitis, a painful and potentially dangerous condition.

In the UK, triglycerides are usually measured as part of a lipid profile alongside total cholesterol, HDL and non-HDL cholesterol, and results are reported in millimoles per litre (mmol/L).

Reading your result

Reference ranges differ slightly between laboratories, but the following bands are commonly used in UK practice and in European guidelines:

NICE guidance on lipid modification allows non-fasting samples for routine cardiovascular risk assessment, reflecting the European consensus led by Nordestgaard and colleagues that fasting is not usually required. If triglycerides are high on a non-fasting sample, a repeat after a 10–12 hour fast is common.

High triglycerides often go hand in hand with low HDL cholesterol, a larger waist, raised blood glucose and high blood pressure — a cluster known as metabolic syndrome. Looking at the pattern is more informative than any single number.

Very high triglycerides also make it difficult for laboratories to calculate LDL cholesterol accurately, so your report may show a note or a directly measured value instead.

What raises triglycerides in active people

Even fit people can have high results. Common contributors include:

• alcohol, especially binge drinking the night before a test;
• very high intake of sugars and refined carbohydrate, for example during aggressive bulking;
• eating a large meal shortly before a blood sample;
• excess body fat, insulin resistance and type 2 diabetes;
• underactive thyroid, kidney disease and some genetic disorders;
• medicines such as some beta blockers, thiazide diuretics, oral oestrogens, retinoids and corticosteroids.

Anabolic-androgenic steroids are best known for lowering HDL and raising LDL; their effect on triglycerides is less consistent. Growth hormone and some other performance drugs can impair glucose metabolism, indirectly affecting lipids. Being open with your doctor about any such use allows correct interpretation.

Recent exercise can temporarily lower triglycerides, so an unusually good value the morning after a long session is not necessarily representative.

How to bring triglycerides down

Triglycerides respond well to lifestyle changes. Reviews by Durstine and colleagues and by Mann and co-workers show that regular aerobic exercise reliably reduces triglycerides, with resistance training providing additional benefit for some people.

Dietary measures with the clearest effect are cutting back on alcohol, reducing added sugars and refined carbohydrate, achieving weight loss if overweight, and including oily fish. Omega-3 fatty acids at higher, prescribed doses lower triglycerides; the REDUCE-IT trial by Bhatt and colleagues showed cardiovascular benefit with a purified prescription form, icosapent ethyl, in high-risk patients.

Over-the-counter fish oil capsules vary in content and should not be used as a substitute for prescribed treatment when triglycerides are very high. Statins and other lipid-lowering medicines are prescribed according to overall cardiovascular risk, as described in NICE and ESC/EAS guidance.

Before retesting, avoid alcohol for at least 24–48 hours, keep your usual diet and avoid an unusually hard session the day before, so the result reflects your normal state.

Conclusions of the editorial team

Triglycerides offer a useful window into how your body handles fat and carbohydrate. For most athletes they are low, but alcohol, aggressive bulking, insulin resistance and some medicines or drugs can raise them.

A value below 1.7 mmol/L is desirable; higher readings call for a look at lifestyle and secondary causes, and very high results need prompt medical review because of the risk of pancreatitis.

Interpreting the number alongside HDL, non-HDL cholesterol, glucose and blood pressure gives a far clearer picture than looking at triglycerides in isolation.

For related reading, see our articles on cholesterol tests for athletes, alcohol and muscle mass, and how anabolic steroids affect blood lipids.

References

1. Mach F, Baigent C, Catapano AL, et al. 2019 ESC/EAS Guidelines for the management of dyslipidaemias: lipid modification to reduce cardiovascular risk. Eur Heart J. 2020;41(1):111–188.
2. Nordestgaard BG, Langsted A, Mora S, et al. Fasting is not routinely required for determination of a lipid profile: clinical and laboratory implications including flagging at desirable concentration cut-points. Eur Heart J. 2016;37(25):1944–1958.
3. National Institute for Health and Care Excellence. Cardiovascular disease: risk assessment and reduction, including lipid modification. NICE guideline NG238. London: NICE; 2023.
4. Durstine JL, Grandjean PW, Davis PG, et al. Blood lipid and lipoprotein adaptations to exercise: a quantitative analysis. Sports Med. 2001;31(15):1033–1062.
5. Mann S, Beedie C, Jimenez A. Differential effects of aerobic exercise, resistance training and combined exercise modalities on cholesterol and the lipid profile: review, synthesis and recommendations. Sports Med. 2014;44(2):211–221.
6. Bhatt DL, Steg PG, Miller M, et al. Cardiovascular risk reduction with icosapent ethyl for hypertriglyceridemia. N Engl J Med. 2019;380(1):11–22.
7. https://steroidstorejapan.com/