Vitamins B12 and D: A simple, senior‑friendly guide to staying healthy

Who this guide is for

  • Older adults, especially ages 70–80+
  • Caregivers supporting seniors
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Quick takeaways

  • As we age, it gets harder to absorb some vitamins—especially vitamin B12 and vitamin D.
  • Low B12 can affect memory, mood, balance, and blood health.
  • Low vitamin D can weaken bones and muscles and raise the risk of falls and fractures.
  • A simple blood test can check your levels. Most people improve with safe supplementation guided by a clinician.
  • Next step: Schedule a vitamin screening and review your medications with a healthcare professional.

Why vitamins matter more as we age

  • Our stomach makes less acid and intrinsic factor over time. This can reduce absorption of vitamin B12 from foods.
  • Older skin makes less vitamin D from sunlight—about 75% less than younger skin.
  • Common medicines (for heartburn, diabetes, seizures, and more) can affect vitamin absorption.

Vitamin B12 (cobalamin)

What B12 does

  • Supports brain and nerve health
  • Helps make red blood cells and DNA
  • Aids energy and balance

Who is at higher risk

  • Adults 60+ and people with low stomach acid
  • People taking acid‑reducing medicines (proton pump inhibitors such as omeprazole, lansoprazole; H2 blockers such as famotidine)
  • People with gastrointestinal conditions (celiac disease, Crohn’s disease), history of weight‑loss surgery, or pernicious anemia
  • Strict vegetarians/vegans without fortified foods or supplements

Common signs and symptoms

  • Numbness or “pins and needles” in hands or feet
  • Trouble with balance or walking; weakness or fatigue
  • Memory loss, confusion, low mood
  • Pale or yellow skin, swollen tongue
  • Anemia

When to get tested

  • If you have any symptoms above, are 60+, or take long‑term acid‑reducing medicines
  • Ask for: serum B12. If results are borderline, ask about methylmalonic acid (MMA) and homocysteine tests, which can detect functional B12 deficiency.

Safe ways to restore B12

  • Food sources: meat, poultry, fish, eggs, dairy, fortified cereals/plant milks
  • Supplements:
    • Oral B12 works well for most people, even with absorption issues, when taken in adequate doses. Forms include cyanocobalamin and methylcobalamin.
    • Injections may be used for severe deficiency or pernicious anemia.
    • Sublingual B12 is an option, but it has not been shown to be superior to standard oral tablets for most people.
  • Important note: High folic acid can mask anemia caused by B12 deficiency while nerve damage continues. If you take folic acid, ensure your B12 status is checked.

Daily needs and safety

  • Recommended intake for adults: 2.4 mcg/day (more for pregnancy/breastfeeding).
  • B12 has no established upper limit in healthy people; excess is typically excreted. Always follow your clinician’s advice.

Vitamin D (D3: cholecalciferol; D2: ergocalciferol)

What vitamin D does

  • Supports strong bones and teeth
  • Helps muscles work well (important for balance and fall prevention)
  • Supports immune health

Who is at higher risk

  • Adults 70+
  • People with little sun exposure or darker skin tones
  • Individuals with obesity, liver/kidney disease, or fat‑malabsorption
  • People taking certain medications (some anticonvulsants, glucocorticoids)

Health effects of low vitamin D

  • Weak muscles, bone loss (osteopenia/osteoporosis), and fractures
  • Higher fall risk
  • Possible links with other health issues; talk to your clinician about your personal risk

When to get tested

  • If you have bone pain, frequent falls, weak muscles, or risk factors above
  • Ask for: 25‑hydroxyvitamin D [25(OH)D] blood test
  • Many clinicians consider 20–50 ng/mL adequate for most adults. Your doctor may set a personalized target.

Safe ways to improve vitamin D

  • Sensible sun exposure: Short, regular mid‑day exposure can help, but balance with skin cancer prevention. Use sunscreen after brief exposure, wear protective clothing, and follow your dermatologist’s advice.
  • Food sources: fatty fish (salmon, mackerel, tuna), fish liver oils, fortified milk/plant milks, fortified cereals, egg yolks
  • Supplements:
    • Vitamin D3 (cholecalciferol) is commonly used and effective.
    • Follow your clinician’s instructions, especially if you have kidney, liver, or parathyroid issues.

Daily needs and safety

  • Recommended intake: adults 19–70 years: 600 IU (15 mcg) daily; adults 71+: 800 IU (20 mcg) daily
  • Upper limit (do not exceed without medical supervision): 4,000 IU (100 mcg) daily for adults
  • Very high doses over time can cause harm. Always consult your clinician before taking more than recommended.

Simple next steps

  1. Book a vitamin screening: Ask your clinician for B12 and 25(OH)D blood tests.
  2. Bring your medication list: Include acid reducers, seizure meds, steroids, and supplements.
  3. Discuss results and plan: Review target levels, food choices, and safe supplement doses.
  4. Set reminders: Take supplements consistently and re‑test as advised.

FAQs

Can I get enough B12 and D from food alone?
Sometimes, but many older adults need supplements, especially for vitamin D and in cases of low B12 absorption.
Is sublingual B12 better than pills?
For most people, regular oral B12 works as well as sublingual. Your clinician will guide you if injections are needed.
How fast will I feel better after starting B12?
Some people feel more energy in weeks, but nerve symptoms can take longer. Follow up with testing to confirm improvement.
What is the safest way to get vitamin D from the sun?
Brief, regular exposure can help, but use sun protection to prevent skin damage. Many seniors still need supplements.
Should I take folic acid with B12?
Be careful: folic acid can mask B12‑related anemia. Ask your clinician to check B12 before taking folic acid.