What is the most common cause of beriberi?

October 31, 2025 •

3 min read

According to the National Institutes of Health, beriberi is most common in regions where the diet includes unenriched, processed white rice. This condition is primarily caused by a deficiency of thiamine, also known as vitamin B1, and affects the nervous and cardiovascular systems.

Quick Summary

A thiamine (vitamin B1) deficiency is the root cause of beriberi. Key risk factors include diets heavy in polished rice or refined carbohydrates and chronic alcohol use, which impairs absorption. Early detection and treatment are crucial to prevent severe, irreversible damage.

Key Points

Thiamine Deficiency: Beriberi is caused by a lack of thiamine, also known as vitamin B1.
Polished Rice: Historically, a diet high in polished white rice was the leading cause, as the milling process removes thiamine.
Chronic Alcoholism: In developed countries, chronic alcohol use disorder is the most common cause due to its negative impact on thiamine absorption.
Absorption Issues: Conditions like bariatric surgery, chronic diarrhea, and some illnesses can impair the body's ability to absorb thiamine.
Two Types: The condition presents as wet beriberi (affecting the heart) or dry beriberi (affecting the nerves).
Preventive Measures: A balanced diet with whole grains and fortified foods is the best way to prevent the condition.

Understanding the Thiamine Deficiency that Causes Beriberi

Beriberi is a debilitating disease resulting from a severe deficiency of thiamine (vitamin B1). Thiamine is an essential nutrient that the body requires to convert carbohydrates into energy and ensure the proper function of nerve cells and the cardiovascular system. Without a sufficient supply, the body's metabolic processes are severely impaired, leading to the various symptoms associated with the condition. While rare in developed countries due to food fortification, beriberi persists in other parts of the world and among specific at-risk populations.

The Historical and Modern Causes

Historically, the most common cause of beriberi was a diet consisting almost exclusively of polished white rice. The milling process that turns brown rice into white rice removes the outer husk, or bran, which is rich in thiamine. In populations where polished rice was the staple food and little else was eaten, this led to widespread outbreaks. The link between polished rice and beriberi was established in the late 19th and early 20th centuries by pioneering medical researchers.

In modern developed nations, the primary cause of beriberi has shifted to other factors, with chronic alcoholism being the most significant. Alcohol interferes with the absorption, metabolism, and storage of thiamine in several ways, while also contributing to poor overall nutritional intake.

Other Factors Contributing to Thiamine Deficiency

While diet and alcoholism are major contributors, several other factors can increase an individual's risk of developing a thiamine deficiency leading to beriberi:

Gastrointestinal Disorders: Conditions like Crohn's disease and chronic diarrhea can impair the body's ability to absorb thiamine from food.
Bariatric Surgery: Gastric bypass and other weight-loss surgeries can lead to malabsorption, increasing the risk of deficiency.
Chronic Illnesses: People with cancer, HIV/AIDS, or those undergoing kidney dialysis have a higher risk due to altered nutritional needs and compromised health.
High Carbohydrate Intake: Diets excessively high in carbohydrates can increase the body's thiamine requirement, potentially exacerbating a pre-existing deficiency.
Increased Need: Pregnant or breastfeeding women and those with hyperthyroidism have an increased metabolic rate, which elevates the body's demand for thiamine.

Comparing Beriberi Causes: Historical vs. Modern


Factor	Historical Primary Cause	Modern Primary Cause (Developed Countries)
Diet	Unenriched, polished white rice as a staple	Poor nutritional intake associated with chronic alcoholism
Underlying Condition	General malnutrition in populations relying on processed staples	Chronic alcoholism, gastrointestinal disorders, and post-bariatric surgery
Absorption	Availability of thiaminases in raw fish and shellfish	Impaired absorption and storage due to alcohol and other diseases
Socioeconomic Status	Widespread among lower classes in rice-dependent areas	Concentrated in specific high-risk populations, regardless of income
Prevention Method	Rice fortification or dietary diversity	Supplementation and addressing underlying health conditions

The Health Consequences of Thiamine Deficiency

When thiamine levels drop, two main types of beriberi can occur, affecting different systems of the body. Wet beriberi primarily impacts the cardiovascular system, leading to rapid heart rate, heart enlargement, and sometimes heart failure. It can also cause fluid buildup, or edema, in the legs, which is a significant clinical sign. Dry beriberi, on the other hand, affects the nervous system and can cause nerve damage. Symptoms include muscle weakness or paralysis, pain, tingling, and numbness in the extremities. In severe and untreated cases, particularly in chronic alcoholics, a serious form of brain damage known as Wernicke-Korsakoff syndrome may develop.

Conclusion

While a diet lacking in thiamine is the direct and most common cause of beriberi, the specific reasons for this deficiency differ significantly across populations. Historically, the reliance on polished rice was the leading cause, particularly in parts of Asia. Today, especially in developed nations, chronic alcohol misuse is the primary driver due to its inhibitory effects on thiamine absorption and storage. Other medical conditions and dietary choices also contribute. The reversibility of damage caused by beriberi depends on the promptness of treatment with thiamine supplements, emphasizing the critical importance of early diagnosis and intervention. A balanced diet rich in thiamine and proper management of risk factors are essential preventative measures.

For more information on the history of this condition, you can explore detailed historical records on sites like the National Institutes of Health.

Frequently Asked Questions

The single most common cause of beriberi is a severe deficiency of thiamine (vitamin B1) in the body. This can result from a diet lacking in thiamine-rich foods or other medical conditions affecting its absorption and use.

Historically, yes. The processing of white rice removes the outer husk where thiamine is concentrated. In regions where polished rice is a staple food, this leads to a higher incidence of beriberi.

Chronic alcoholism is a common cause in developed nations because it interferes with the body's ability to absorb, store, and metabolize thiamine. Heavy drinkers often also have poor nutritional intake.

The two main types are wet beriberi, which affects the cardiovascular system and can cause heart failure, and dry beriberi, which affects the nervous system, leading to nerve damage and muscle issues.

Wernicke-Korsakoff syndrome is a severe form of brain damage that can result from long-term, untreated thiamine deficiency, particularly in people with alcoholism. It causes confusion, memory loss, and other neurological symptoms.

You can prevent beriberi by consuming a balanced diet rich in thiamine, found in foods like whole grains, nuts, seeds, and fortified cereals. Limiting alcohol consumption also significantly reduces risk.

Beriberi is rare in developed countries where food is often fortified with vitamins. However, it still occurs in regions with malnutrition and in specific high-risk populations, such as chronic alcoholics and people with certain medical conditions.