Understanding Who is Most at Risk for Vitamin B1 Deficiency

October 14, 2025 •

2 min read

According to the National Institutes of Health, chronic alcoholism is the most common cause of thiamine deficiency in industrialized countries, affecting up to 80% of individuals with chronic alcohol use disorder. However, many other groups are also susceptible, making it crucial to understand who is most at risk for vitamin B1 deficiency.

Quick Summary

Chronic alcoholism, restrictive diets, bariatric surgery, certain medical conditions, and advanced age significantly increase the risk of thiamine deficiency. The condition can lead to severe neurological and cardiovascular complications like beriberi and Wernicke-Korsakoff syndrome, which can be life-threatening if left untreated.

Key Points

Chronic Alcoholism: A leading cause of thiamine deficiency in developed nations due to poor nutrition and impaired absorption caused by alcohol consumption.
Post-Bariatric Surgery: Gastric bypass and other weight-loss surgeries can lead to malabsorption, making supplementation crucial for these patients.
Poor Diet: Diets high in refined carbohydrates and low in whole grains, legumes, and nuts can lead to inadequate thiamine intake.
Medical Conditions: Diseases like HIV/AIDS, cancer, and chronic diarrhea, along with liver disease and hyperthyroidism, increase the risk of deficiency.
Elderly Individuals: Older adults can have lower dietary intake and impaired thiamine absorption, increasing their susceptibility.
Infants of Deficient Mothers: Exclusive breastfeeding by a thiamine-deficient mother can lead to infantile beriberi, which has a very high fatality rate if untreated.
Diuretic Use: Long-term use of certain diuretics can increase the body's excretion of thiamine.

Key Risk Groups for Thiamine Deficiency

While severe thiamine deficiency, historically known as beriberi, is rare in industrialized nations, certain populations remain highly vulnerable. Understanding these risk factors is vital for prevention and early intervention. These at-risk groups can generally be categorized based on lifestyle, dietary habits, and underlying medical conditions.

Lifestyle and Dietary Factors

Several lifestyle and dietary factors can significantly deplete the body's thiamine stores:

Chronic Alcoholism: Alcohol interferes with thiamine absorption, storage, and conversion, making individuals with chronic alcoholism the highest risk group.
Poor Diet and Malnutrition: Diets high in refined carbohydrates and low in thiamine-rich foods, as well as malnutrition from eating disorders like anorexia nervosa, increase risk.
Excessive Coffee or Tea Consumption: Large amounts of coffee or tea can inhibit thiamine absorption due to compounds called tannins.
Dietary Habits in Resource-Poor Areas: Reliance on thiamine-deficient staple foods like polished rice is a primary cause of deficiency in these regions.

Medical Conditions Increasing Risk

Various health issues can compromise thiamine levels.

Gastrointestinal Surgeries: Procedures like bariatric surgery can lead to malabsorption of thiamine.
Conditions Causing Malabsorption: Chronic diarrhea and inflammatory bowel diseases can interfere with thiamine absorption.
Chronic Diseases: Conditions such as HIV/AIDS, cancer, liver disease, and diabetes can impact thiamine intake or metabolism. Individuals with diabetes may have lower thiamine levels due to increased excretion.
Hypermetabolic States: Conditions that increase metabolic rate, like hyperthyroidism or pregnancy, increase the demand for thiamine.
Kidney Dialysis: Dialysis can remove water-soluble vitamins like thiamine from the blood.
Medication Use: Some diuretics, such as furosemide, can increase thiamine excretion.

Comparison of Key Risk Factors


Risk Factor Category	Examples	Mechanism of Action	Affected Populations
Lifestyle & Diet	Chronic alcoholism, polished rice diet, anorexia nervosa, excessive coffee/tea	Reduced absorption, impaired storage/metabolism, inadequate intake of thiamine-rich foods.	Alcoholics, people with eating disorders, institutionalized individuals, populations in resource-poor areas.
Medical Conditions	Bariatric surgery, malabsorption syndromes, chronic diseases (HIV, diabetes), hyperthyroidism, kidney dialysis	Increased metabolic demand, impaired absorption due to altered gut function, medication-induced excretion.	Post-surgery patients, individuals with specific chronic illnesses, pregnant/lactating women.

Recognizing and Preventing Deficiency

Symptoms of thiamine deficiency can be non-specific, including fatigue, irritability, memory issues, and loss of appetite. Severe cases can result in beriberi or Wernicke-Korsakoff syndrome.

Prevention involves a balanced diet rich in thiamine, found in whole grains, lean pork, legumes, and nuts. Fortified cereals also contribute to thiamine intake in the general population. High-risk individuals, including those undergoing alcohol withdrawal, may require medical supervision and supplementation. Treatment can involve oral or intravenous thiamine. For more information, consult the National Institutes of Health: Thiamin - Health Professional Fact Sheet.

Conclusion

Vitamin B1 deficiency poses a risk to specific populations. Chronic alcohol use and gastrointestinal issues are common factors in developed countries, while poor diet remains a global concern. Identifying risk factors, recognizing symptoms, and utilizing effective treatment are crucial for preventing serious complications like nerve damage and heart failure. Timely intervention can often reverse effects and prevent long-term damage.

Frequently Asked Questions

In industrialized countries, chronic alcoholism is the most common cause of thiamine (vitamin B1) deficiency because alcohol interferes with its absorption, storage, and metabolism.

Bariatric surgery, such as gastric bypass, alters the digestive system and reduces nutrient absorption, leading to a higher risk of thiamine deficiency and other nutritional deficiencies.

Eating disorders like anorexia nervosa lead to poor overall nutritional intake and malnutrition, significantly increasing the risk of thiamine deficiency.

Yes, excessive consumption of polished white rice, white flour, and other highly processed carbohydrates can cause deficiency. Also, chronic consumption of large amounts of coffee or tea may inhibit thiamine absorption.

Early symptoms are often vague and include fatigue, irritability, poor memory, loss of appetite, and mild nerve sensations like tingling in the extremities.

Wet beriberi primarily affects the cardiovascular system, leading to heart failure and edema, while dry beriberi affects the nervous system, causing nerve damage and muscle weakness.

Wernicke-Korsakoff syndrome is a severe and acute brain disorder caused by prolonged thiamine deficiency, most commonly associated with chronic alcoholism, and can result in memory loss, confusion, and nerve issues.