High or low triglycerides in athletes

Triglycerides respond to lifestyle faster than any other indicator of the lipidogram. Therefore, their deviation from the norm is often a clue that there has been a change in nutrition, training or health. The editors analyzed why triglycerides in a person who trains can be high or, on the contrary, very low, and what to do about it.

What values are considered a deviation

According to the 2019 ESC/EAS guidelines, the desired fasting triglyceride level is less than 1.7 mmol/L. Values ​​above are considered hypertriglyceridemia, which increases cardiovascular risk, and a level above 10 mmol/l is considered severe hypertriglyceridemia with a high risk of acute pancreatitis.

For non-fasting tests, the EAS/EFLM consensus suggests a guideline of 2.0 mmol/L. Therefore, having received an "increased" result, it is first of all worth checking whether the conditions of preparation have been met.

There is virtually no lower limit of normal for triglycerides in most laboratories: low values ​​are rarely clinically significant in themselves. However, very low triglycerides combined with other changes can indicate certain conditions, which are discussed below.

Because triglycerides fluctuate greatly, the diagnosis of hypertriglyceridemia is made on the basis of repeated measurements, rather than a single analysis.

Elevated triglycerides: food and sports causes

The most common cause is an excess of energy, especially from simple sugars and fructose. The liver converts excess carbohydrates into fat and releases it into the blood as VLDL. Bulking athletes who add sugary drinks, high-sugar gainers, and desserts to their diet often see their triglycerides rise.

The second common cause is alcohol. Even moderate amounts can raise triglycerides in sensitive people, and when combined with fatty foods, the effect is amplified. Celebrating after the competition on the eve of the analysis is a typical situation that "spoils" the lipidogram.

The third is carbohydrate loading. A protocol of dramatically increasing carbohydrate intake while decreasing training volume for several days prior to an endurance event can temporarily raise triglycerides. This is a physiological reaction that passes after returning to the usual mode.

The fourth is a sharp decrease in activity. During an injury or off-season, when training stops and the diet remains "sports", triglycerides can increase, because the muscles no longer utilize fats with the former intensity.

Medical and medicinal reasons

Among the metabolic causes in the first place are insulin resistance, prediabetes and type 2 diabetes. High triglycerides combined with low HDL and abdominal obesity is a typical sign of metabolic syndrome. The AHA scientific statement (Miller et al., 2011) emphasizes that this profile is associated with increased cardiovascular risk.

Other medical reasons: hypothyroidism, chronic kidney disease, nonalcoholic fatty liver disease, pregnancy. There are also genetic disorders, from common polymorphisms that increase the response to diet to the rare familial chylomicronemia syndrome with extremely high triglycerides.

A number of drugs increase triglycerides. These include systemic retinoids (isotretinoin, which is often prescribed for acne), glucocorticoids, oral estrogens, some beta-blockers and thiazide diuretics, and certain antipsychotics and antiretrovirals. In athletes who are treated for steroid-related acne, the combination of factors can be particularly unfavorable.

Anabolic androgenic steroids primarily lower HDL and increase LDL; their effect on triglycerides is less consistent. Growth hormone and insulin without medical indications disrupt carbohydrate and fat metabolism, and insulin, in addition, carries the risk of severe hypoglycemia, which can be fatal.

Low triglycerides: when to pay attention

Low triglycerides are usually normal in an endurance athlete. High activity of lipoprotein lipase in the muscles and high sensitivity to insulin ensure the rapid use of fats from the blood.

However, very low values ​​combined with weight loss, fatigue, menstrual irregularities, or frequent injuries may indicate an energy deficiency. The International Olympic Committee consensus on relative energy deficiency syndrome in sport (Mountjoy et al., 2023) describes a wide range of metabolic and hormonal consequences of this condition.

Other possible causes are hyperthyroidism, including that caused by taking thyroid hormones for pre-competition weight cutting, intestinal malabsorption (for example, with celiac disease), long-term very low-fat diet.

Taking high-dose fish oil and lipid-lowering drugs also lower triglycerides—this is an expected effect, not an aberration.

What to do in case of deviations

Lifestyle is the main tool for moderately elevated triglycerides. The reaction is usually visible after several weeks, which makes this indicator convenient for evaluating the effectiveness of changes.

1. Check the conditions of the analysis and repeat it on an empty stomach, without alcohol for 1-2 days and without unusual loads.
2. Limit alcohol, sugary drinks, juices, and foods with added sugar.
3. Adjust caloric intake to load: during periods of less activity, reduce the amount of fast carbohydrates.
4. Increase your intake of oily fish or consider omega-3 supplements after consulting your doctor.
5. Take additional tests: glucose, HbA1c, TSH, liver enzymes, creatinine.

Omega-3 fatty acids EPA and DHA reduce triglycerides in a dose-dependent manner. The AHA scientific opinion (Skulas-Ray et al., 2019) notes that a dose of about 4 g per day of prescription forms lowers triglycerides in people with severe hypertriglyceridemia; such doses are used under the supervision of a doctor. The REDUCE-IT study (Bhatt et al., 2019) showed a reduction in cardiovascular events with icosapentayl ethyl in high-risk patients with elevated triglycerides.

If triglycerides exceed 10 mmol/L or abdominal pain, nausea, or vomiting occur, urgent medical attention is required because of the risk of pancreatitis. Pharmacotherapy (fibrates, statins, prescription omega-3) is prescribed by a doctor.

Editorial conclusions

Elevated triglycerides in an athlete are most often associated with sugar, alcohol, caloric surplus, or decreased activity, but may indicate insulin resistance, hypothyroidism, or medication. Low values ​​are usually normal for endurance athletes, but in combination with weight loss, it is a signal of a possible energy deficit.

Triglycerides quickly respond to changes in lifestyle, so dynamic control allows you to assess the result in just a few weeks. Very high values ​​require urgent evaluation by a doctor.

The editors also recommend reading Triglycerides: What the Analysis Shows and Why It Matters to the Athlete, Apolipoprotein B: What the Analysis Shows and Why It Matters to the Athlete, and our review of omega-3 fatty acids in sports nutrition.

List of used literature

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. Miller M, Stone NJ, Ballantyne C, et al. Triglycerides and cardiovascular disease: a scientific statement from the American Heart Association. Circulation. 2011;123(20):2292–2333.
3. Skulas-Ray AC, Wilson PWF, Harris WS, et al. Omega-3 fatty acids for the management of hypertriglyceridemia: a science advisory from the American Heart Association. Circulation. 2019;140(12):e673–e691.
4. 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.
5. Nordestgaard BG, Langsted A, Mora S, et al. Fasting is not routinely required for determination of a lipid profile. Eur Heart J. 2016;37(25):1944–1958.
6. Mountjoy M, Ackerman KE, Bailey DM, et al. 2023 International Olympic Committee's (IOC) consensus statement on Relative Energy Deficiency in Sport (REDs). Br J Sports Med. 2023;57(17):1073–1097.