What Deficiency Causes Cold Hands and Feet with Fever?

October 30, 2025 •

5 min read

During a fever, the body’s internal thermostat is reset to a higher temperature to fight off infection, a process that can make extremities feel cold as blood is redirected to the vital organs. While this is a normal physiological response, underlying issues can intensify the sensation, making you wonder what deficiency causes cold hands and feet with fever. Several nutritional shortfalls, particularly those impacting red blood cell production and circulation, can exacerbate this effect.

Quick Summary

Cold hands and feet with fever are often due to the body's thermoregulation prioritizing core temperature. However, deficiencies like iron and vitamin B12 can worsen these symptoms by affecting blood circulation and nerve function. Other medical conditions also present with similar symptoms, necessitating professional medical evaluation for an accurate diagnosis.

Key Points

Normal Thermoregulation: Feeling cold in extremities during a fever is a natural response as the body redirects blood flow to vital organs to conserve heat.
Iron-Deficiency Anemia: A lack of iron reduces hemoglobin and oxygen transport, impairing circulation and making hands and feet feel colder.
Vitamin B12 Deficiency: A deficit in B12 can cause anemia and nerve damage (neuropathy), contributing to poor circulation and cold sensations.
Magnesium's Role: Low magnesium levels can cause blood vessels to constrict, reducing blood flow to the hands and feet.
Other Conditions to Consider: Other illnesses like hypothyroidism, Raynaud's, or diabetes can also cause cold extremities and should be medically evaluated.
Professional Diagnosis is Key: Do not self-diagnose based on these symptoms; always consult a healthcare professional for a proper diagnosis and treatment plan.
Treatment Addresses the Root Cause: Addressing the underlying deficiency or medical condition is the most effective way to alleviate persistent or severe cold extremity symptoms.

The Body's Natural Response: Thermoregulation During Illness

When the body battles an infection, it initiates a fever to create an inhospitable environment for pathogens. This process is managed by the hypothalamus in the brain, which acts as the body’s thermostat. To raise the core body temperature, the body triggers several mechanisms:

Vasoconstriction: Blood vessels in the skin and extremities (hands and feet) narrow, reducing blood flow to these areas to conserve heat. This is a primary reason for the sensation of coldness in the hands and feet during a fever.
Shivering: The body induces muscle contractions to generate heat.
Blood Redistribution: Blood is shunted away from the periphery to the core organs to keep them warm and functioning optimally.

This is why feeling cold and shivery is a common experience during a fever, despite an elevated internal temperature. However, for some individuals, this phenomenon is more pronounced or persistent, and nutritional deficiencies are a contributing factor.

Key Deficiencies Exacerbating Cold Extremities

While a deficiency itself does not cause the fever, it can significantly worsen the symptom of cold hands and feet. The primary culprits are those that lead to anemia or impair proper circulation.

Iron-Deficiency Anemia and Poor Oxygen Transport

One of the most common deficiencies is an insufficient level of iron, which leads to iron-deficiency anemia. Iron is a crucial component of hemoglobin, the protein in red blood cells that transports oxygen throughout the body. When iron is lacking, the body cannot produce enough healthy, oxygen-carrying red blood cells, resulting in:

Reduced Oxygen Supply: Less oxygen reaching the muscles and tissues means the body operates less efficiently, and less heat is generated in the extremities.
Poor Circulation: The heart must work harder to circulate the limited supply of oxygenated blood, which can contribute to poor circulation, particularly to the hands and feet, making them feel colder.

Common symptoms of iron-deficiency anemia include fatigue, pale skin (pallor), headaches, and shortness of breath, in addition to cold hands and feet.

Vitamin B12 Deficiency and Nerve Damage

Vitamin B12 is essential for the production of healthy red blood cells and maintaining the protective sheath around nerves. A deficiency can lead to megaloblastic anemia and peripheral neuropathy. Without enough healthy red blood cells, the body experiences poor oxygen circulation similar to iron-deficiency anemia, causing cold hands and feet. Nerve damage from B12 deficiency can also cause numbness, tingling, and a cold sensation in the extremities, even if they aren't physically cold to the touch.

Magnesium's Role in Circulation

Magnesium is involved in over 300 biochemical reactions in the body, including those that regulate muscle and nerve function. A deficiency can cause muscle cramps and spasms, but it can also lead to poor circulation. Magnesium helps relax blood vessel walls, and low levels can cause them to constrict, reducing blood flow to the extremities. This impaired circulation can make cold hands and feet more noticeable, especially during a fever when the body is already shunting blood to the core.

Comparison of Key Deficiencies Affecting Thermoregulation


Deficiency	Primary Role	Effect on Thermoregulation	Associated Symptoms (Beyond Cold Extremities)
Iron	Hemoglobin production, oxygen transport.	Leads to anemia and reduced oxygen transport, causing poor circulation and cold extremities.	Fatigue, pale skin, headaches, shortness of breath, pica.
Vitamin B12	Red blood cell production, nerve function.	Causes anemia and nerve damage (peripheral neuropathy), leading to poor circulation and cold sensations.	Numbness, tingling, fatigue, weakness, cognitive impairment.
Magnesium	Muscle and nerve function, blood vessel dilation.	Impairs circulation by causing blood vessels to constrict, leading to poor blood flow to extremities.	Muscle cramps, spasms, irregular heart rhythm, heightened senses.

Other Conditions That Mimic or Contribute to Symptoms

It is crucial to remember that nutritional deficiencies are not the only cause of cold hands and feet, especially in combination with a fever. Several medical conditions can either mimic or worsen these symptoms:

Hypothyroidism: An underactive thyroid gland slows metabolism, reducing the body's heat production and circulation, which can cause increased sensitivity to cold.
Raynaud's Phenomenon: This condition causes the blood vessels in the fingers and toes to overreact to cold or stress, severely limiting blood flow and making them feel cold and numb.
Diabetes: High blood sugar can cause nerve damage (peripheral neuropathy) and narrow blood vessels, impairing circulation and leading to cold hands and feet.
Peripheral Artery Disease (PAD): Plaque buildup in the arteries restricts blood flow to the limbs, causing them to feel cold.
Dehydration: Blood volume decreases when dehydrated, making circulation less efficient and reducing blood flow to extremities.

What to Do If You Have Symptoms

If you experience cold hands and feet with a fever, it is important to address the fever first, as it is often a sign of an active infection. Staying hydrated and getting sufficient rest are key. If the symptoms of cold extremities persist even after the fever has resolved or are accompanied by other symptoms, seeking medical attention is essential. A doctor can run blood tests to check for nutritional deficiencies and other conditions to determine the correct course of action. It is also important to address underlying health conditions to prevent them from worsening.

Treatment and Dietary Interventions

Based on a proper diagnosis, a doctor may recommend dietary changes or supplementation. For example, treating iron-deficiency anemia often involves taking iron supplements and increasing intake of iron-rich foods like red meat, beans, and spinach. For a B12 deficiency, supplements or injections may be necessary, along with consuming B12-rich foods like meat, fish, and dairy. Magnesium intake can be boosted with nuts, seeds, and leafy greens. However, any supplementation should be guided by a healthcare professional.

Conclusion

While feeling cold in your hands and feet during a fever is a normal bodily response to conserve heat, certain nutritional deficiencies can make the sensation more pronounced. Iron and vitamin B12 deficiencies, in particular, impair circulation and nerve function through anemia, while a magnesium deficiency can affect blood vessel function. The combination of these deficiencies with a fever's natural thermoregulation can intensify symptoms. Given that other serious medical conditions can also cause these issues, it is crucial to consult a healthcare provider for an accurate diagnosis and treatment plan rather than assuming a deficiency is the sole cause. Proper diagnosis and targeted intervention are the most effective ways to manage symptoms and address the root cause of the problem.

Disclaimer: This article is for informational purposes only and does not constitute medical advice. Consult a healthcare professional for diagnosis and treatment.

Frequently Asked Questions

Yes, it is a normal physiological response. During a fever, your body raises its core temperature by constricting blood vessels in the extremities, like your hands and feet, to divert heat to your vital organs.

An iron deficiency itself does not typically cause a fever. However, iron deficiency anemia can weaken the immune system, potentially making you more susceptible to infections that could lead to a fever.

Anemia, including that caused by iron or B12 deficiencies, reduces the number of red blood cells and hemoglobin, which are responsible for carrying oxygen. Poor oxygenation leads to impaired circulation, causing hands and feet to feel cold.

Yes, a severe vitamin B12 deficiency can lead to peripheral neuropathy, a condition involving nerve damage. This can cause neurological symptoms such as tingling, numbness, and cold sensations in the extremities.

Magnesium is vital for relaxing blood vessels. A deficiency can cause blood vessels to constrict, which impairs blood flow, especially to the furthest parts of the body like the hands and feet, making them feel cold.

Several other medical conditions can cause cold hands and feet, including hypothyroidism, Raynaud's phenomenon, diabetes, and Peripheral Artery Disease (PAD).

You should see a doctor if your cold hands and feet are persistent, severe, or accompanied by other symptoms such as fatigue, weakness, pale skin, or nerve-related issues. This is especially true if it persists after a fever has subsided.

Good sources of iron include red meat, beans, and spinach. For B12, consider meat, dairy, and fortified cereals. For magnesium, leafy greens, nuts, and seeds are excellent options.