Triglycerides are a type of fat found in your blood, serving as a primary energy source. They are formed from the foods you eat and from extra calories your body converts and stores in fat cells. While high triglyceride levels receive much attention, low levels are also being studied for their association with various health conditions, including cancer. This article explores the nature of triglycerides and their observed connections to cancer.
Understanding Triglyceride Levels
Triglycerides are organic compounds formed from glycerol and three fatty acids, serving as the main form of fat storage in humans and plants. Your body obtains triglycerides from dietary fats, such as butter and oils, and also produces them in the liver from excess calories, alcohol, and sugar. These fats are then stored in fat cells throughout the body and released by hormones to provide energy between meals.
A blood test measures triglyceride levels, typically after a period of fasting, in milligrams per deciliter (mg/dL). Levels below 150 mg/dL are generally considered within a normal range. While there isn’t a universally agreed-upon “low” threshold, levels consistently below 50 mg/dL are often considered low and may warrant further investigation.
Common non-cancer-related causes of low triglycerides include:
Very low-fat or low-carbohydrate diets
Certain medications like statins or high-dose omega-3 fatty acids
An overactive thyroid (hyperthyroidism)
Malnutrition
Malabsorption disorders such as celiac disease or Crohn’s disease
Some genetic conditions
The Connection Between Low Triglycerides and Cancer
Research indicates an association between low triglyceride levels and the presence or increased risk of various cancers. This connection is primarily observed through epidemiological studies, highlighting a correlation rather than a direct cause-and-effect relationship. For instance, some studies note that cancer patients, particularly those with advanced disease, often present with lower-than-average triglyceride levels.
This observation has been made across different cancer types, though the strength of the association can vary. Some research suggests that low triglyceride levels might be seen in patients with hematological malignancies and certain solid tumors. The presence of low triglycerides may be part of a broader metabolic picture in individuals with cancer, but it does not definitively diagnose cancer.
Potential Reasons for the Association
The observed association between low triglycerides and cancer may stem from several hypothesized biological mechanisms.
Metabolic Reprogramming
Cancer cells exhibit metabolic reprogramming, meaning they alter their metabolic pathways to support rapid growth and proliferation. This involves increased uptake and consumption of lipids, including triglycerides, to meet their high energy and structural demands for building new cell membranes. Tumor cells can also enhance their de novo lipid synthesis, further impacting systemic lipid levels.
Cancer Cachexia
Cancer cachexia, a wasting syndrome common in advanced cancer, also contributes to altered lipid metabolism. This condition involves significant loss of both fat and muscle tissue, which can lead to reduced circulating lipid levels, including triglycerides. Cachexia is characterized by increased lipolysis, the breakdown of fat, and can involve the mobilization of fatty acids from adipose tissue, potentially leading to lower triglyceride stores.
Systemic Inflammation and Liver Dysfunction
Systemic inflammation, a common feature in many cancers, can further influence lipid profiles. Chronic inflammation disrupts normal lipid metabolism, affecting how the body produces, transports, and utilizes fats.
Liver dysfunction, which can occur in cancer due to the disease itself or its treatments, may also play a role. The liver is central to triglyceride synthesis, and impaired liver function could lead to reduced production of these fats. The body’s immune response to cancer may also impact lipid profiles, as immune cells themselves undergo metabolic changes that can affect systemic lipid levels.
What Low Triglycerides Could Mean for You
If your triglyceride levels are consistently low, it does not automatically mean you have cancer. Low triglycerides can result from various benign factors, as discussed earlier. However, if low triglyceride levels are noted during a routine blood test, especially without a clear explanation, it warrants a conversation with a healthcare professional.
A doctor will consider your complete health picture, including your medical history, lifestyle, and other symptoms you might be experiencing. Low triglycerides can sometimes serve as an indicator, prompting further investigation to rule out any underlying conditions, including but not limited to cancer. It is a piece of information that contributes to a broader diagnostic assessment rather than a standalone tool for diagnosing cancer.