💊 Should I Take a Multivitamin?

Food first, supplements second! 🍎 While a multivitamin can be a smart "insurance policy," it should never replace a diet rich in whole foods, like the fish, fruits, and nuts pictured here. Do you actually need a daily multivitamin? We break down who benefits the most—including pregnant women, seniors, and patients taking GLP-1 medications or those with Chronic Kidney Disease (CKD)—and why certain supplements should be avoided depending on your health.

By Kidney MD | Vitamins & Minerals Simplified Series

Walk into any pharmacy and you’ll find entire aisles of vitamins promising more energy, sharper focus, and better health. But do most people actually need a multivitamin every day? The answer depends on you — your diet, lifestyle, and medical needs.

🌿 For Most Healthy Adults

If you generally eat a balanced diet and have no major health conditions, a daily multivitamin is usually not necessary. Large research studies show that routine multivitamin use does not lower your risk of heart disease, cancer, or death.

That means if your meals already include:

• Colorful fruits and vegetables (vitamins A, C, K, B-complex)

• Whole grains and legumes (B-vitamins, magnesium)

• Low-fat dairy or fortified plant milk (calcium, vitamin D)

• Lean proteins and seafood (iron, zinc, vitamin B12, omega-3s)

…you’re likely meeting your needs through food.

However, short periods of low intake — due to stress, busy schedules, or restrictive eating — are common. In those times, a basic, moderate-dose multivitamin can help fill small gaps. Look for:

• No more than 100 % of the daily value for most nutrients

• Third-party certification (USP, NSF, or ConsumerLab)

• Avoiding megadoses (> 300 % DV) or “high-potency” blends unless prescribed

🩺 Kidney MD tip: Think of a multivitamin as an insurance policy — it can fill gaps but can’t replace a healthy diet.

🧍‍♀️ Who Might Need Extra Support

Certain groups are more likely to develop deficiencies and can benefit from daily supplementation:

• Pregnant or planning pregnancy: need folic acid (400–800 mcg daily) to prevent birth-defect risks.

• Adults over 60: may absorb less vitamin B12 and vitamin D.

• Vegans or vegetarians: need reliable vitamin B12, and sometimes iron and zinc.

• People with restrictive diets or poor appetite: may not meet needs for calcium, magnesium, or iron.

• People taking certain medications:

  • Methotrexate users often need folate (vitamin B9) supplementation to prevent side effects.

  • Metformin (commonly used for diabetes) can lower vitamin B12 over time, so periodic monitoring and supplementation may be needed.

🩺 Kidney MD tip: If you’re on long-term medications, ask your clinician if any vitamins or minerals should be checked regularly — sometimes simple supplementation can prevent fatigue, nerve issues, or anemia before they start.

💉 For People Using GLP-1 Medications

GLP-1 receptor agonists (e.g., semaglutide, tirzepatide, liraglutide) help with weight loss and diabetes by reducing appetite and slowing digestion. While effective, this can also mean eating much less — sometimes under 1,200–1,800 calories per day — which may not provide enough nutrients.

🔍 Commonly Low Nutrients on GLP-1s

• Vitamin D

• Vitamin B12 and folate

• Iron

• Calcium, magnesium, and zinc

  
  

If you’ve noticed appetite suppression, nausea, or skipping meals, you may benefit from a daily multivitamin or targeted supplements.We recommend:

• Baseline labs for vitamin D, B12, iron, and ferritin before starting treatment

• Re-checking every 3–6 months, especially if losing weight quickly

• Pairing supplementation with protein-rich, nutrient-dense foods (e.g., eggs, fish, yogurt, lentils, leafy greens)

  
  

🩺 Kidney MD tip: Not every GLP-1 user needs a multivitamin — but if your diet shrinks or varies little, one can prevent fatigue, hair loss, or dizziness related to low nutrients.

⚖️ After Bariatric (Weight-Loss) Surgery

After procedures like gastric sleeve or gastric bypass, your body can no longer absorb vitamins and minerals as efficiently. That means lifelong supplementation is essential.

Standard Post-Bariatric Recommendations

• Multivitamin: a bariatric-specific formula taken daily

• Vitamin B12: 350–500 mcg daily or monthly injection

• Iron: 45–60 mg elemental iron daily (for menstruating females and bypass procedures)

• Folate: 400–800 mcg daily (up to 1,000 mcg for women of childbearing age)

• Thiamine (B1): at least 12 mg daily

• Calcium + Vitamin D: as prescribed based on labs

Even with supplementation, regular lab monitoring (every 3–6 months the first year, then yearly) is essential to prevent anemia, neuropathy, and bone loss.

🩺 Kidney MD tip: Consistency matters more than brand — skipping doses for weeks or months can lead to serious deficiencies.

🩸 For People with Chronic Kidney Disease (CKD)

Nutrient needs in CKD are unique because of dietary restrictions and changes in how the kidneys handle vitamins and minerals.

CKD (Not on Dialysis)

• Focus: Balanced intake; avoid unnecessary supplements.

• Commonly low: Vitamin D, sometimes B-vitamins or iron.

• Avoid high doses of vitamins A and E — they can accumulate and become toxic.

• Ask about: a renal-specific multivitamin if appetite is poor or diet is limited.

ESRD / Dialysis Patients

Dialysis removes water-soluble vitamins, so supplementation is often necessary.Most dialysis patients are prescribed a renal multivitamin that includes:

• B-complex vitamins (B1, B2, B6, B12, folate)

• Vitamin C in moderate doses

• Zinc and selenium if levels are low

However, vitamins A and E should not be taken unless your clinician prescribes them. Vitamin D and iron are usually given separately and require close monitoring.

🩺 Kidney MD tip: Always check your current labs before starting anything new — what’s “healthy” for the general population may not be safe in CKD.

🍎 The Bottom Line

• Most healthy adults can meet nutrient needs from food alone.

• Multivitamins may help during periods of low intake or for specific populations (pregnant, older adults, restricted diets).

• People on GLP-1s, post-bariatric, or with CKD/ESRD often need targeted supplementation and lab monitoring.

• Food first, supplements second — real foods provide fiber, antioxidants, and plant nutrients that pills can’t match.

✅ Takeaway from Kidney MD

A multivitamin isn’t a magic bullet — but it can be a smart safety net for those at risk of deficiencies. Talk to your clinician before starting one, especially if you have kidney disease or take GLP-1 medications.