The Mineral Mix: Calcium, Magnesium, Iron & More

Your mineral heroes come from your plate! 🍽️ This image showcases the wide variety of whole foods—from lean proteins (Iron) and nuts (Magnesium) to dark leafy greens (Calcium)—that naturally provide the essential minerals your body needs. Before reaching for a supplement, prioritize a balanced diet. If you have kidney disease, remember that balance is key; some minerals, like Sodium, Potassium, and Phosphorus, require careful, individualized monitoring.

By Kidney MD | Vitamins & Minerals Simplified Series

Vitamins often get all the attention, but minerals are the quiet heroes that keep your body functioning. They build your bones, move your muscles, carry oxygen, and balance your fluids.

Let’s look at the most important minerals — what they do, where to find them, and how to keep levels in check for both general wellness and kidney health.

🦴 Calcium – The Bone Builder

What it does: Keeps bones and teeth strong, helps muscles contract, supports heartbeat and nerve transmission.Where to get it: Dairy products, fortified plant milks, sardines, tofu, leafy greens (collards, kale).

Too little: Can cause bone loss, muscle cramps, or brittle nails.Too much: May lead to kidney stones or interfere with absorption of other minerals.

🩺 Kidney MD tip:People with chronic kidney disease (CKD) need individualized calcium goals. Some may require calcium binders; others should limit supplements to prevent calcification of blood vessels. Always review calcium intake and lab results with your clinician.

⚡ Magnesium – The Calmer Mineral

What it does: Helps regulate muscle and nerve function, blood sugar, and blood pressure; supports sleep and relaxation.Where to get it: Nuts, seeds, whole grains, beans, leafy greens, dark chocolate.

Too little: Can cause fatigue, cramps, irregular heartbeat, or poor sleep.Too much (from supplements): May lead to diarrhea or low blood pressure.

🩺 Kidney MD tip:Magnesium levels can drop in people using GLP-1 medications, diuretics, or after bariatric surgery. In advanced kidney disease, excess magnesium can build up — so supplements should be taken only if recommended.

❤️ Iron – The Oxygen Carrier

What it does: Builds hemoglobin, the protein that carries oxygen to your tissues.Where to get it: Lean meats, beans, lentils, tofu, spinach, fortified cereals.

• Heme iron (from meat) is absorbed best.

• Non-heme iron (from plants) is better absorbed with vitamin C–rich foods.

Too little: Causes anemia, fatigue, dizziness, hair loss.Too much: Can cause constipation or damage organs if taken in excess.

🩺 Kidney MD tip:Iron deficiency is common in CKD and dialysis. Your care team may recommend oral or IV iron based on ferritin and TSAT levels. Avoid self-supplementing without lab guidance.

🧘 Zinc – The Immune and Healing Mineral

What it does: Boosts immune response, helps wounds heal, supports taste and smell.Where to get it: Seafood, pumpkin seeds, beans, nuts, whole grains.Low levels: May cause slow wound healing, frequent infections, or hair loss.

🩺 Kidney MD tip: Zinc deficiency can occur with poor intake, dialysis, or GLP-1–related appetite suppression. Low-dose supplementation (8–11 mg/day) is safe, but high doses can lower copper levels — balance matters.

🧬 Selenium – The Antioxidant Partner

What it does: Protects cells from oxidative stress and supports thyroid function.Where to get it: Brazil nuts (just 1–2 nuts meet your daily need!), tuna, eggs, sunflower seeds.Too much: Chronic high intake can cause hair loss, fatigue, or a garlic-like breath odor.

🩺 Kidney MD tip: Selenium deficiency is more common in dialysis patients and those on restrictive diets. A balanced renal multivitamin usually provides safe replacement amounts.

🧂 Sodium, Potassium, and Phosphorus – The Balancers

These minerals regulate fluid, muscle, and nerve function — but balance is key.

Mineral	Function	Too Much	Too Little	Kidney MD Guidance
Sodium	Maintains fluid & blood pressure	Raises BP, causes swelling	Fatigue, low BP	Limit processed foods; aim <2,300 mg/day
Potassium	Heart & muscle function	Dangerous heart rhythms in CKD	Weakness, cramps	Adjust intake based on kidney labs
Phosphorus	Bone & cell structure	Bone loss, calcification	Rare	Limit additives & sodas if kidney function reduced

🩺 Kidney MD tip:If you have CKD or are on dialysis, phosphorus and potassium often need careful monitoring. “Hidden” phosphorus in processed foods is a major source — check ingredient labels for words ending in -phosphate.

🍎 Putting It All Together

• Eat a variety of whole foods to naturally meet mineral needs.

• Drink enough water and avoid over-the-counter “mega-minerals.”

• If you have CKD, are post-bariatric, or on GLP-1 therapy, discuss supplements and labs with your clinician.

🩺 Kidney MD takeaway:

Minerals keep your body in balance — but too much of a good thing can strain your kidneys. Smart, individualized intake matters more than quantity.