Triglycerides are a type of fat, or lipid, that circulates in the bloodstream, serving primarily as the body’s energy reserve. They are synthesized from excess calories and stored in fat cells for later use between meals. Public health discourse consistently emphasizes the dangers of high triglyceride levels due to their association with cardiovascular disease risk. This focus often leaves people confused when a blood test reveals a result on the opposite end of the spectrum. This article clarifies the meaning of a low triglyceride reading and explores whether such a result indicates a health concern.
Defining Low Triglycerides
The medical community generally defines a normal or desirable fasting triglyceride level as anything below 150 milligrams per deciliter (mg/dL). This optimal range is associated with a lower risk of heart-related issues, suggesting that lower levels are beneficial for most individuals. When discussing low triglycerides, the concern shifts from heart disease risk to the possibility of an underlying health problem.
While a reading below 150 mg/dL is considered normal, a clinically low triglyceride level is typically defined as below 50 mg/dL. Investigation is often warranted when levels dip even lower, sometimes below 40 mg/dL or 35 mg/dL. A moderately low level within the normal range is usually a sign of good health, but a pathologically low reading requires careful investigation to identify the root cause.
Underlying Reasons for Low Readings
A low triglyceride count can often be traced to lifestyle choices, with restrictive diets being a common factor. Individuals maintaining an extremely low-fat diet or severe calorie restriction may not consume enough fats and carbohydrates for adequate triglyceride production. Intense, sustained aerobic exercise also contributes to lower readings by increasing the body’s rate of energy utilization and burning stored energy quickly.
Certain medications prescribed for high cholesterol can significantly lower triglyceride levels as an intended side effect. Drug classes such as fibrates and statins, commonly used to manage lipid profiles, are known to reduce circulating triglycerides. High-dose fish oil supplements, which contain omega-3 fatty acids, are another non-prescription intervention that can drive levels down.
Beyond diet and medication, several underlying health conditions may be responsible for a low reading. An overactive thyroid (hyperthyroidism) accelerates the body’s metabolism, causing energy stores to be consumed quickly. Since the liver plays a primary role in producing and metabolizing triglycerides, liver disease can impair this function, leading to reduced levels.
Conditions that cause severe malabsorption, such as celiac disease or Crohn’s disease, prevent the small intestine from properly absorbing nutrients, including dietary fats, even when food intake is adequate. In rare instances, extremely low triglyceride levels may signal a genetic disorder that severely impairs lipid metabolism, such as abetalipoproteinemia. A truly low reading, especially below 40 mg/dL, often signals that one of these underlying issues is present and requires medical attention.
Potential Health Risks Associated with Deficiency
When triglyceride levels become pathologically low, the body’s ability to perform essential functions can be compromised. Triglycerides are necessary for transporting fat-soluble vitamins (A, D, E, and K) from the digestive tract into the bloodstream. Impairment of this transport mechanism can lead to nutrient deficiencies and associated symptoms.
Deficiencies in these fat-soluble vitamins can manifest as vision problems (low Vitamin A) or bone density issues (insufficient Vitamin D). The body also relies on triglycerides as a readily available energy source between meals. When this energy reserve is depleted, a person may experience symptoms like chronic fatigue, weakness, or difficulty maintaining concentration.
In the most severe cases, particularly those caused by rare genetic defects, the deficiency can lead to significant neurological complications. These disorders can be associated with symptoms like nerve damage and issues with muscle coordination. For vulnerable populations, such as those with advanced systemic illness or malnutrition, very low triglycerides may reflect a depleted metabolic reserve, predicting worse health outcomes.
Management and Next Steps
If a blood test reveals a triglyceride level that falls into the clinically low range, the first step is to consult a healthcare provider. The primary focus of the medical evaluation is to determine the underlying cause of the low reading, as the number itself is often a symptom rather than the main problem. This process typically involves a detailed review of the person’s diet and medication use, including supplements like high-dose fish oil.
Further diagnostic testing may be necessary to rule out conditions like hyperthyroidism or malabsorption disorders. If the cause is purely dietary, healthy adjustments can be made to safely increase levels. Incorporating sources of healthy fats, such as avocados, nuts, seeds, and olive oil, can help restore balance. A physician can provide guidance on appropriate dietary changes and determine whether a low reading is a benign result of a healthy lifestyle or a signal of a more serious condition.