Symptom → lab tests
Why am I always cold? Blood tests that check the common causes
Short answer
Feeling cold when others are comfortable is a classic hypothyroid symptom and a common sign of anemia or low iron. TSH (with Free T4 if abnormal), a CBC and ferritin cover the main causes; vitamin B12 is added because deficiency causes both anemia and cold, tingling extremities.
Medically reviewed by Youmna DiStefano, MD · Last reviewed September 2026
When should you see a clinician instead of ordering a test?
- Fingers or toes turning white or blue with numbness (Raynaud's) — see a clinician
- Cold intolerance with a very slow heart rate, confusion or extreme sluggishness — seek care promptly
Why these tests for always feeling cold?
Thyroid hormone drives heat production, so an underactive thyroid lowers body temperature tolerance. Anemia — from iron, B12 or folate deficiency — reduces oxygen delivery and leaves hands and feet cold. Low body weight and poor circulation are non-lab causes a clinician will consider.
Which conditions do these tests help evaluate?
- Thyroid Problems — TSH, Free T4/T3 and antibodies to evaluate an under- or over-active thyroid.
- Anemia — CBC, iron studies, ferritin, B12 and folate to find the cause of fatigue and low energy.
Which tests, and what do they cost?
Prices are cash-pay; every order adds one $6 lab processing fee. Physician authorization is included; no insurance or referral needed.
| Test or panel | Type | Price | Fasting | Results |
|---|---|---|---|---|
| Complete Thyroid PanelSaves $10.97 vs ordering the tests separately | Panel · 4 tests | $109.99 | No | 3–7 business days |
| Baseline Anemia PanelSaves $56.96 vs ordering the tests separately | Panel · 5 tests | $74.99 | Yes | 2–4 business days |
| TSH (Thyroid Stimulating Hormone) | Test | $26.99 | No | 1–3 business days |
| Free T4 (Thyroxine) | Test | $23.99 | No | 1–3 business days |
| CBC with Differential | Test · 14 biomarkers | $21.99 | No | 1–3 business days |
| Ferritin | Test | $24.99 | No | 1–3 business days |
| Vitamin B12 | Test | $25.99 | No | 2–4 business days |
Common questions
Can low iron make you cold without anemia?
Yes. Iron deficiency affects temperature regulation before hemoglobin drops, which is why ferritin is checked alongside the CBC.
Educational content, not a diagnosis. Lab results are one input; a clinician interprets them with your history and exam.