What Deficiency Causes Keshan Disease?

January 2, 2026 •

4 min read

In the 1960s, extensive epidemiological studies conducted in China revealed a strong correlation between low selenium levels in local foods and the occurrence of Keshan disease. This critical research ultimately concluded that a selenium deficiency is the major nutritional cause behind this rare and life-threatening form of heart disease.

Quick Summary

Keshan disease, an endemic cardiomyopathy, is mainly caused by a dietary selenium deficiency. It is most prevalent in regions with selenium-poor soil, such as certain areas of China. Viral cofactors and genetic factors can exacerbate the condition, leading to heart failure and other complications.

Key Points

Selenium Deficiency: Keshan disease is primarily caused by a severe deficiency of the trace mineral selenium.
Multifactorial Cause: While a key factor, selenium deficiency alone isn't the sole cause; viral infections (like Coxsackievirus), genetic factors, and malnutrition also play a role.
Endemic Location: The disease is endemic to specific rural, mountainous regions, most notably a belt stretching across China, where the soil is poor in selenium.
Population at Risk: It disproportionately affects children and women of childbearing age in these regions.
Cardiomyopathy: The condition manifests as a severe and potentially fatal form of cardiomyopathy, causing heart failure, enlarged heart, and arrhythmias.
Effective Prevention: Mass selenium supplementation programs, implemented through fortified table salt and food, have drastically reduced the disease's incidence.
Treatment: Treatment for Keshan disease involves selenium supplementation, often in combination with supportive medical therapy for heart failure.

Understanding the Complex Etiology of Keshan Disease

First identified in 1935 in Keshan County, China, this severe form of heart disease, known as cardiomyopathy, baffled medical experts for decades. The breakthrough in understanding the condition arrived with the establishment of the link to selenium deficiency, a discovery that underscored the profound impact of trace mineral nutrition on public health. While selenium deficiency is the primary cause, Keshan disease is widely considered a multifactorial condition influenced by several environmental, biological, and genetic factors.

The Role of Selenium in Cardiac Health

Selenium is a crucial trace mineral that the human body cannot produce on its own, making dietary intake essential. It is a key component of selenoproteins, a class of enzymes vital for various physiological processes, including antioxidant defense.

Antioxidant Protection: Selenium-dependent enzymes, such as glutathione peroxidase (GPx), protect heart muscle cells from oxidative stress and damage caused by free radicals. In individuals with Keshan disease, low selenium levels lead to reduced GPx activity, leaving the heart vulnerable to damage.
Immune Response: Selenium also plays a crucial role in immune function. A deficiency can compromise the immune system, potentially allowing for other infections to flourish and cause harm.
Viral Interaction: Research has found that selenium deficiency can promote the mutation of coxsackievirus B3 (CVB3) into a more virulent strain that specifically targets the heart muscle. This demonstrates a synergistic relationship where the virus can worsen heart damage in an already weakened, selenium-deficient host.

Contributing Factors to Keshan Disease

While selenium deficiency is a necessary condition for Keshan disease, it is not always sufficient on its own. Other factors play a compounding role.

Viral Infections: The presence of the Coxsackievirus B3 (CVB3) is a major contributing factor. In selenium-deficient individuals, this virus can become more harmful, leading to more severe myocardial injury.
Genetic Predisposition: Not all individuals living in selenium-deficient areas develop Keshan disease, suggesting a genetic component. Specific gene mutations or polymorphisms, such as in the GPx-1 gene, may increase susceptibility.
Environmental Toxins: Some theories have pointed to environmental toxins, like mycotoxins from contaminated grains, as potential exacerbating agents.
Nutritional Imbalances: Deficiencies in other nutrients, such as vitamin E, have also been suggested to contribute to the disease, as selenium and vitamin E often work synergistically as antioxidants.

Comparison of Key Disease Characteristics


Feature	Keshan Disease	Idiopathic Dilated Cardiomyopathy (DCM)
Primary Cause	Severe selenium deficiency, often compounded by viral infection.	Unknown etiology; may involve genetic factors, viral infections, or autoimmune responses.
Geographic Distribution	Endemic to specific regions with low soil selenium content, predominantly in rural China.	Global, not confined to specific low-mineral regions.
Affected Population	Primarily children and women of childbearing age in endemic areas.	Can affect individuals of any age or gender.
Treatment Focus	Specific selenium supplementation is the primary and most effective intervention.	Standard heart failure treatment with medication (e.g., ACE inhibitors, beta-blockers) and potential device therapy.
Diagnosis Consideration	Requires evaluation of selenium status and residence in an endemic area, along with cardiac symptoms.	Diagnosis of exclusion; requires ruling out other causes of heart disease.

Diagnosis and Management

Diagnosing Keshan disease involves a combination of clinical evaluation and laboratory tests. A patient's residence in an endemic, low-selenium area, coupled with characteristic cardiac symptoms, is a strong indicator. Blood tests can confirm low selenium levels and reduced glutathione peroxidase activity. Imaging studies like an electrocardiogram (ECG) and echocardiogram reveal heart abnormalities, such as arrhythmias or enlargement.

Once diagnosed, the primary treatment is selenium supplementation, often with sodium selenite, which has been shown to significantly reduce the incidence and mortality rates. For managing the heart failure symptoms, standard cardiology care, including diuretics and other medications, is also employed. In severe, advanced cases, more invasive treatments like cardiac surgery may be necessary.

Prevention Strategies

The most effective way to prevent Keshan disease is to ensure adequate selenium intake, especially in at-risk populations. Public health measures implemented in China have been highly successful and can be replicated elsewhere.

Dietary Diversification: People living in endemic areas can increase their selenium intake by consuming a wider variety of foods sourced from outside the deficient zone.
Selenium Fortification: Large-scale programs involving the supplementation of table salt and fertilizer with selenium have proven to be very effective in reducing disease incidence.
Supplementation Programs: Regular oral selenium supplementation for at-risk populations, particularly children and women of childbearing age, is a direct and effective preventive measure.

Conclusion

Keshan disease is a historically significant and geographically specific form of cardiomyopathy definitively linked to a selenium deficiency. The etiology is not singular but multifactorial, involving interactions with viruses, especially coxsackievirus, and potential genetic predispositions. Fortunately, the condition is now largely preventable and treatable through targeted selenium supplementation and broader public health initiatives. Continued vigilance, early detection, and proper nutritional management are key to improving the health outcomes for affected populations in endemic areas and working towards the disease's global elimination. For more on public health successes, consult publications on nutritional epidemiology, such as those found on the website of the National Institutes of Health.

Frequently Asked Questions

The primary nutritional cause of Keshan disease is a severe deficiency of the essential trace mineral selenium, often due to low selenium content in the soil and food chain of endemic regions.

Keshan disease is most prevalent in specific rural, mountainous regions of China where the soil is known to have extremely low levels of selenium.

No, selenium deficiency is not the only cause. It is considered a primary factor, but the condition is also influenced by viral infections (specifically Coxsackievirus), genetic predispositions, and other nutritional deficiencies like vitamin E.

Keshan disease causes a specific type of cardiomyopathy characterized by multifocal necrosis and fibrosis of the heart muscle. This can lead to an enlarged heart, heart failure, and severe arrhythmias.

Children and women of childbearing age living in the endemic, low-selenium regions are most susceptible to developing Keshan disease.

Keshan disease is prevented by ensuring adequate selenium intake. This can be achieved through mass supplementation programs, such as providing selenium-fortified table salt, and through a more diverse diet including foods from outside endemic areas.

Symptoms vary depending on the disease type (acute, subacute, chronic, latent) but can include fatigue, dizziness, nausea, shortness of breath, heart palpitations, and congestive heart failure.

Yes, Keshan disease is treatable. The primary treatment involves selenium supplementation, often combined with conventional heart failure medications. Early intervention is crucial for improving patient outcomes.