Which vitamin deficiency causes swollen feet?

January 7, 2026 •

3 min read

According to medical experts, a severe deficiency of vitamin B1, known as thiamine, can lead to a condition called wet beriberi, which is a major cause of swollen feet. This is because the lack of thiamine impairs cellular energy production and can lead to fluid accumulation in the body's tissues, including the extremities.

Quick Summary

Thiamine (B1) deficiency is a primary vitamin-related cause of swollen feet, a symptom of wet beriberi. The article details how this and other vitamin deficiencies affect fluid balance. It also covers non-vitamin causes, diagnosis, and treatment options for managing edema.

Key Points

Thiamine (B1) Deficiency: The most common vitamin-related cause of swollen feet, leading to a condition called wet beriberi due to impaired heart function and fluid buildup.
Scurvy (Vitamin C Deficiency): A severe lack of vitamin C can cause weakened blood vessels and spontaneous bleeding, leading to edema in the extremities.
Mineral Influence: Deficiencies in minerals such as magnesium and potassium can also disrupt the body's fluid balance and contribute to swelling.
Beyond Vitamins: Swollen feet can be caused by more serious underlying health issues like heart, kidney, and liver disease, not just nutritional deficits.
Effective Treatments: Management includes addressing the specific deficiency with supplementation, adopting a low-sodium diet, elevating the legs, and wearing compression socks.
Balanced Diet: A diet rich in pork, fish, whole grains, and leafy vegetables is essential for maintaining adequate levels of key B vitamins and minerals.

Swollen feet, a medical condition known as edema, is often caused by a buildup of excess fluid in the body's tissues. While many health issues can cause this symptom, certain vitamin deficiencies can disrupt the body's fluid regulation. A deficiency in thiamine (vitamin B1) is a key culprit, but it's important to understand other potential vitamin and mineral links as well.

The Primary Culprit: Thiamine (Vitamin B1) Deficiency

The most significant vitamin deficiency causing swollen feet is thiamine deficiency, which can manifest as wet beriberi. Thiamine is crucial for metabolizing carbohydrates and producing energy in the body. When deficient, it can lead to impaired heart function, causing fluid to back up and pool in the lower extremities, resulting in swelling of the feet and legs. This form of edema can be severe and life-threatening.

Other Related Nutritional Deficiencies

While B1 is the most direct cause, other deficiencies can play a supporting role in causing or worsening fluid retention.

Vitamin C: Severe vitamin C deficiency (scurvy) can lead to weakened capillaries and poor connective tissue formation, potentially resulting in edema in the lower extremities.
Vitamin B6: Some studies suggest a link between B6 deficiency and fluid retention, particularly related to PMS. However, severe deficiency is less common due to wide availability in foods.
Magnesium and Potassium: These minerals are vital for regulating fluid balance. Deficiencies in either can lead to water retention and swelling.

Beyond Vitamins: Other Causes of Swollen Feet

Swollen feet can indicate various underlying conditions beyond vitamin deficiency. These include:

Heart and Kidney Disease: Impaired function of these organs can lead to edema due to poor fluid pumping or filtering.
Chronic Venous Insufficiency: Damaged leg vein valves can cause blood pooling and swelling.
Injury and Infection: Localized swelling can occur due to the body's response to damage or infection.
Lifestyle Factors: Standing or sitting for extended periods, high sodium intake, and certain medications can also cause fluid retention.

Sources of Thiamine and Other Nutrients

A balanced diet is crucial for preventing deficiencies. Key sources include:

Best Sources of Vitamin B1 (Thiamine):

Pork
Fish (salmon, tuna)
Beans, peas, lentils
Sunflower seeds
Enriched and fortified whole grains

Best Sources of Vitamin B6 (Pyridoxine):

Chickpeas
Salmon
Bananas
Potatoes
Poultry

Best Sources of Vitamin C:

Citrus fruits
Peppers
Broccoli
Strawberries
Kiwi

Comparing Vitamin Deficiency Symptoms


Deficiency	Primary Symptom	Mechanism	Other Key Symptoms
Thiamine (B1)	Swollen Feet (Wet Beriberi)	Impaired glucose metabolism, poor energy production, heart failure.	Heart failure, tingling, muscle weakness, confusion.
Vitamin C	Swollen Joints, Bruising (Scurvy)	Weakened capillaries, poor collagen formation, hemorrhages.	Bleeding gums, slow wound healing, fatigue, joint pain.
Vitamin B6	Skin Rashes, Nerve Issues	Impaired nerve function and neurotransmitter synthesis.	Numbness, 'pins and needles', confusion, glossitis.
Magnesium/Potassium	Fluid Retention	Disruption of cellular sodium-potassium pumps, electrolyte imbalance.	Muscle cramps, irregular heartbeat (potassium), fatigue.

Treating Vitamin Deficiency Edema

Treatment involves addressing the nutritional cause with diet and/or supplementation. Thiamine deficiency requires prompt treatment with thiamine supplementation. Additionally, these lifestyle changes can help manage edema:

Elevate the feet: Raising legs above heart level helps drain fluid.
Wear compression socks: Provides pressure to prevent fluid pooling.
Reduce sodium intake: Less salt helps the body retain less water.
Gentle exercise: Improves circulation and reduces fluid buildup.
Stay hydrated: Drinking water can signal the body not to retain fluids.

Conclusion

While multiple factors can cause swollen feet, thiamine (vitamin B1) deficiency is a clear nutritional cause leading to wet beriberi and associated edema. Other deficiencies like vitamins C and B6, and minerals like magnesium and potassium, also impact fluid retention. A medical evaluation is crucial for accurate diagnosis and treatment. A balanced, nutrient-rich diet and healthy habits can help prevent and manage edema related to vitamin deficiencies. More information on diagnosing thiamine deficiency is available from the National Institutes of Health: Vitamin B1 (Thiamine) Deficiency - StatPearls.

Frequently Asked Questions

While less directly linked to common edema than B vitamins, some research notes that vitamin D deficiency might be linked to inflammation and could potentially influence fluid balance, but it is not a primary or classic cause.

Wet beriberi is a cardiovascular form of thiamine (vitamin B1) deficiency characterized by heart abnormalities and fluid accumulation, particularly in the legs and feet, due to the heart's inability to pump blood efficiently.

With proper treatment, including intravenous thiamine in severe cases, recovery from swelling due to wet beriberi can begin relatively quickly, though supportive measures and continued supplementation are often necessary.

Yes, many factors unrelated to vitamin deficiency can cause swollen feet, including prolonged standing, high sodium intake, heart failure, kidney disease, pregnancy, and certain medications.

Good sources of vitamin B1 include pork, fish, nuts and seeds (like sunflower seeds), beans and lentils, and fortified whole-grain cereals and rice.

Severe vitamin C deficiency (scurvy) is not a common modern cause of swollen feet but can cause edema and bleeding problems. It is typically associated with other symptoms like bleeding gums and poor wound healing.

You should see a doctor if swelling is sudden, severe, worsens, or is accompanied by other symptoms like chest pain, shortness of breath, or numbness.