Total Cholesterol 143 mg/dL: Is That Low?

Is Total Cholesterol 143 mg/dL Low, Normal, or High?

Total cholesterol 143 mg/dL is considered low based on standard clinical reference ranges. Most health organizations, including the American Heart Association and the National Heart, Lung, and Blood Institute, define desirable total cholesterol as under 200 mg/dL. While being well below that threshold might sound like great news, a reading of 143 mg/dL is unusually low and may warrant a closer look. Your doctor will want to understand why your cholesterol is this low, especially if it has dropped significantly from previous readings. Low total cholesterol is not automatically a problem, but it is worth exploring the full picture behind the number.

A total cholesterol reading of 143 mg/dL places you slightly below the standard reference range, warranting further investigation rather than immediate concern. While many associate lower cholesterol with better health, a value like 143 mg/dL suggests a need to understand why it’s dipping below the optimal threshold of 150-199 mg/dL. One common explanation at this level might be an exceptionally rigorous, very low-fat diet, possibly an overcorrection for previously higher levels, or an intensely active lifestyle combined with a highly restrictive eating pattern. Less frequently, but still worth considering, subtle issues with nutrient absorption or an overactive thyroid could be at play. To gain a clearer picture, typical next steps involve repeating a full lipid panel, which includes LDL, HDL, and triglycerides, alongside a detailed discussion about your diet, medications, and any recent health changes. Depending on these findings, tests for thyroid function or liver health might be recommended. An important detail to understand is that while high cholesterol poses risks, cholesterol that is consistently too low can also be a marker for underlying conditions or, in rare cases, even increase the risk of other health issues, such as hemorrhagic stroke or certain psychological symptoms, a complexity often overlooked in general health discussions. This particular value highlights the importance of balance, not just reduction.

Hidden Risk of Total Cholesterol 143 mg/dL

A total cholesterol of 143 mg/dL often gets overlooked because most conversations about cholesterol focus on high readings. But very low cholesterol carries its own set of concerns that are less commonly discussed. Research from the National Institutes of Health has explored links between very low cholesterol and certain health outcomes that deserve attention.

A total cholesterol level of 143 mg/dL, while seemingly good, can signal underlying issues that increase the risk of certain health complications, particularly concerning nutrient absorption and hormone production. Significantly low cholesterol can impair the body's ability to produce essential hormones like cortisol and sex hormones (estrogen, testosterone), potentially leading to fatigue, mood disturbances, and reproductive issues. Furthermore, cholesterol is vital for cell membrane structure and function; a level this low may compromise cellular integrity and repair processes. While often associated with lower cardiovascular risk, extremely low total cholesterol can paradoxically be linked to an increased risk of hemorrhagic stroke and may indicate malabsorption syndromes that prevent the uptake of fat-soluble vitamins (A, D, E, K), impacting bone health and immune function.

• Some studies have found associations between very low total cholesterol and increased risk of hemorrhagic stroke, though the connection is still being researched
• Cholesterol plays a critical role in hormone production, cell membrane structure, and vitamin D synthesis. Very low levels may affect these processes
• Low cholesterol can sometimes be a sign of an underlying condition such as hyperthyroidism, liver disease, malnutrition, or malabsorption issues
• Certain medications, chronic infections, or severe illness can push total cholesterol unusually low as a secondary effect
• Mental health research has explored potential links between very low cholesterol and mood changes, though findings remain mixed and no firm conclusions have been drawn

What Does a Total Cholesterol Level of 143 mg/dL Mean?

Total cholesterol is a combined measurement of several types of cholesterol and fats in your blood. The basic formula is: total cholesterol equals LDL cholesterol plus HDL cholesterol plus 20 percent of your triglycerides. So when you see a total cholesterol number, it reflects multiple components working together rather than a single type of fat.

A total cholesterol reading of 143 mg/dL is most plausibly explained by a combination of aggressive dietary fat restriction, potentially coupled with significant weight loss or a hyperthyroid state. Individuals meticulously following very low-fat diets, particularly those that eliminate healthy fats, are prone to achieving such low levels. Rapid or substantial weight loss, even if otherwise healthy, can temporarily depress cholesterol synthesis. Additionally, an overactive thyroid gland (hyperthyroidism) accelerates metabolism, including the breakdown of cholesterol, leading to lower circulating levels. Certain medications, like statins or specific cholesterol absorption inhibitors, if taken inappropriately or at high doses for other reasons, could also contribute to reaching this specific value.

Your body needs cholesterol. It is not simply a harmful substance. Cholesterol is essential for building and maintaining cell walls, producing hormones like estrogen and testosterone, creating bile acids that help you digest food, and synthesizing vitamin D. Every cell in your body uses cholesterol as part of its structure.

At 143 mg/dL, your total cholesterol is significantly below the desirable range of 150 to 199 mg/dL. For some people, this is simply their natural baseline driven by genetics, diet, and lifestyle. For others, it could signal that something else is going on. Your doctor will want to look at each component of the lipid panel individually. For example, if your HDL (the protective cholesterol) is very low, even a low total number might not be as reassuring as it first appears.

It is also important to understand that cholesterol levels are just one factor in overall health. A reading of 143 mg/dL does not tell the full story on its own. Your doctor will interpret it alongside your other lab results, medical history, and lifestyle factors to form a complete assessment.

Lifestyle Changes for Total Cholesterol 143 mg/dL

If your total cholesterol is 143 mg/dL and your doctor has ruled out underlying conditions, the focus shifts to making sure your body is functioning well overall. Regular physical activity supports healthy cholesterol balance. The American Heart Association recommends at least 150 minutes of moderate-intensity aerobic exercise per week, such as brisk walking, swimming, or cycling. Exercise tends to raise HDL cholesterol, which is especially important when total cholesterol is on the low side.

For a total cholesterol of 143 mg/dL, the immediate next step is to repeat the lipid panel in 1-3 months to confirm the persistence of this low value, ensuring the test was not affected by recent illness or temporary dietary changes. Focus dietary adjustments on incorporating healthy fats rather than restricting all fats; prioritize sources like olive oil, avocados, nuts, and seeds to support hormone production and vitamin absorption. Monitor for symptoms such as persistent fatigue, mood changes, or digestive issues. Consider a brief consultation with a registered dietitian to refine your nutritional intake, ensuring adequate calories and essential fatty acids without overcorrection. No immediate specialist referral is typically needed unless specific symptoms warrant it.

Maintaining a healthy weight is another key factor. Being significantly underweight can contribute to low cholesterol levels. If weight loss has been unintentional, it is worth mentioning to your healthcare provider. Sustainable body weight management supports stable cholesterol production.

Sleep quality also plays a role in cholesterol regulation. Research suggests that chronic sleep deprivation can alter lipid metabolism. Aiming for seven to nine hours of quality sleep per night supports your body's natural processes, including cholesterol production and balance.

Stress management matters as well. Chronic stress affects your hormonal balance, and since cholesterol is a building block for hormones, prolonged stress may influence your lipid profile in subtle ways. Finding consistent ways to manage stress, whether through exercise, spending time in nature, or simply resting, contributes to overall cardiovascular and metabolic health.

Written by

Ernestas K.

Clinical research writer specializing in human health, biology, and preventive medicine.

Reviewed against AHA, NIH, ACC, Mayo Clinic, PubMed guidelines · Last reviewed March 20, 2026