Overview
Vitamin B1, also known as Thiamine, Anti–Beriberi vitamin, or Antineuritic vitamin, is a water-soluble nutrient essential for carbohydrate metabolism and normal nerve function. According to the document (page 2), its biologically active form—Thiamine Pyrophosphate (TPP)—acts as a key coenzyme in energy production pathways, including the citric acid cycle, and supports nerve impulse transmission, acetylcholine synthesis, and conversion of tryptophan to niacin (page 3).
Vitamin B1 is vital for appetite regulation, muscle tone, and mental health. Since only small amounts are stored in the liver, daily intake from thiamine-rich foods is necessary. The document also highlights beneficial functions such as improving memory, supporting digestion, reducing cataract risk, and preventing age-related cognitive decline (page 4).
Symptoms
Symptoms associated with Vitamin B1 deficiency are detailed across pages 5 and 11 of the document.
1. Neurological Symptoms
Because thiamine is crucial for nerve conduction, deficiency may lead to:
- Poor memory
- Mental depression and irritability
- Peripheral neuropathy
- Numbness or “pins and needles” sensation in the legs
- Wernicke’s encephalopathy
These symptoms reflect impaired neurotransmission and reduced energy supply to nerve cells.
2. Muscular & Cardiovascular Symptoms
The document lists:
- Muscle cramps
- General muscular weakness
- Tachycardia
- Hypotension
- Rapid heart rate
- Difficult breathing
These signs arise from impaired energy metabolism in muscles and the heart.
3. Systemic Symptoms
Other deficiency-related symptoms include:
- Fatigue
- Sleeplessness
- Loss of appetite
- Nausea
- Constipation
Prolonged deficiency leads to the disease Beri-Beri, which develops over approximately four weeks and is defined when Vitamin B1 levels fall below 2 µg/dL (page 13).
Causes
The document provides several biological and lifestyle-related causes of Vitamin B1 deficiency.
1. Low Dietary Intake
Since thiamine is found naturally in foods such as cereals, pulses, nuts, yeast, pork, milk, beans, tomatoes, and mushrooms (page 10), inadequate consumption of these foods is a major cause. Polishing of rice removes nearly 80% of Vitamin B1, making populations dependent on polished rice more susceptible (page 10).
2. Increased Carbohydrate Intake
The document notes that daily thiamine requirements increase with carbohydrate consumption (page 8). High-carb diets without adequate B1 intake can quickly lead to deficiency.
3. Malabsorption Syndromes
Clinical applications on page 12 show that conditions like celiac disease, IBD, and bariatric surgery impair absorption and increase deficiency risk.
4. Alcohol Use Disorder
Chronic alcoholism disrupts thiamine absorption and utilization, contributing to deficiency and Wernicke-Korsakoff syndrome (page 12).
5. Critical Illness
Patients in the ICU with sepsis or hyperemesis are at higher risk due to increased metabolic demand (page 12).
Vitamin B1 toxicity is rare because excess amounts are flushed out through urine, and there is no established toxic level from food sources (page 13).
Risk Factors
Risk factors described in the document include:
1. Poor Nutrition & Food Processing
Low intake of whole grains or reliance on polished rice significantly increases deficiency risk (page 10).
2. Alcohol Dependence
Alcoholism impairs thiamine absorption and storage, making deficiency common (page 12).
3. Medical Conditions Affecting Absorption
Celiac disease, IBD, and post-bariatric surgery patients face chronic malabsorption challenges (page 12).
4. High Energy Demand
Pregnancy, lactation, critical illness, and high-carbohydrate diets raise thiamine needs (page 8 & 12).
5. Unexplained Neuropathy
Individuals with peripheral neuritis or neuropathic symptoms may be at higher risk (page 12).
6. Elderly & Dialysis Patients
These groups often require nutritional monitoring due to reduced intake and loss of water-soluble vitamins (page 12).
Prevention
Prevention strategies in the document focus on maintaining adequate intake, early testing, and proper sample handling.
1. Adequate Dietary Intake
Include foods listed on page 10—cereals, pulses, nuts, yeast, pork, milk, vegetables, and mushrooms—to meet daily requirements.
2. Follow Recommended Daily Allowances
RDA varies by age (page 8):
- Adults: 1.2–1.5 mg/day
- Pregnant/lactating mothers: 1.3–1.5 mg/day
3. Early Laboratory Testing
Testing is recommended when symptoms such as poor memory, fatigue, muscle cramps, or tachycardia appear (page 5).
4. Proper Sample Collection
To prevent inaccurate results (page 6):
- Collect 3 mL of whole blood in EDTA
- Protect the sample from sunlight
- Prefer fasting sample
5. Monitoring High-Risk Groups
Individuals with alcohol dependence, malabsorption syndromes, or severe illness should undergo periodic nutritional assessment (page 12).
6. Ensure Optimal Metabolism
Maintaining balanced carbohydrate intake prevents excess demand for thiamine (page 8).
