Feeling unusually tired, light-headed, cold, or foggy? Those are classic red flags that something in your body is low. "Deficiency" just means your body lacks something it needs — a vitamin, a hormone, or even plain water. The good news: many deficiencies have clear signs and simple fixes you can start today.
Iron: Look for fatigue, pale skin, shortness of breath and heavy periods. A ferritin test and CBC will tell the story. If low, add iron-rich foods like lean red meat, spinach, beans, and fortified cereals. Oral iron supplements help, but check with a doctor because too much iron can be harmful.
Vitamin D: Low energy, bone aches, and low mood are common. A 25-hydroxyvitamin D blood test shows your level. Sunlight helps, plus fatty fish, eggs, and vitamin D3 supplements if needed. Small daily doses are safe for many people; get a test to guide the right amount.
Vitamin B12: Watch for tingling in hands/feet, memory problems, or feeling weak. Older adults and people on certain meds are at higher risk. Test serum B12 and methylmalonic acid if available. Foods: meat, fish, dairy, fortified plant milks. Supplements or injections may be advised based on test results.
Thyroid (hypothyroidism): Cold intolerance, weight gain, fatigue, and slow thinking can signal low thyroid function. A TSH and free T4 test are the first steps. Some people use natural desiccated thyroid (see our article “Is Armour Thyroid Safe?”) but never switch meds without a doctor’s guidance.
Dehydration: Dizziness, headache, dark urine, and dry mouth are easy to spot. Sip water steadily rather than gulping. For mild dehydration, oral rehydration solutions or drinks with electrolytes work well. Severe dehydration needs medical care—don’t delay if someone is fainting or very confused.
1) Match symptoms to likely causes. Use the clues above to narrow things down. 2) Get basic blood tests: CBC, ferritin, 25(OH)D, B12, TSH/free T4. These are the most informative starting points. 3) Adjust your diet first—real food fixes many mild issues. Examples: spinach and lentils for iron, salmon and sunlight for vitamin D, eggs and dairy for B12. 4) If levels stay low, use targeted supplements under a doctor’s advice. Avoid high-dose supplements without testing—more isn’t always better.
If symptoms are severe—fainting, chest pain, breathing trouble, high fever, sudden weakness—seek emergency care. For everything else, a primary care visit plus the tests above will point you to safe, effective treatment options. Read our relevant guides on thyroid meds, dehydration, and vitamins to learn more and make smarter choices with your healthcare provider.
Got odd symptoms and no clue why? Start with a basic panel and a short food and drink diary for a week. That often shows patterns your doctor can act on. Small changes can make a big difference fast.
