Nutrition for Strong Bones: Why Calcium and Vitamin D Are Only Part of the Story

When people think about bone health, two nutrients usually come to mind: calcium and vitamin D. And while those are essential, your bones are far more complex than that. Bone is living tissue - constantly breaking down and rebuilding - and it relies on multiple nutrients working together to stay strong, resilient, and metabolically active.

If long-term bone health is your goal (and it should be!), it’s time to expand beyond the basics. Here are the six key nutrients that matter most, and the whole-food strategies to help you get them.

1. Protein: The Structural Framework of Bone

Most people don’t realise that bone is about 50% protein by volume. Collagen - a structural protein - forms the framework that minerals attach to. Without enough dietary protein, bones can become brittle even when calcium intake is adequate.

Whole-food protein sources

Aim to include high-quality protein at each meal:

• Beef, lamb, chicken, turkey

• Fish and seafood (especially sardines, salmon, snapper)

• Eggs

• Greek yoghurt or cottage cheese

• Tofu and tempeh

• Legumes (lentils, chickpeas, beans)

• Nuts and seeds

  
  

2. Calcium: Essential, But Not in Isolation

Calcium provides the mineral hardness that gives bone its rigidity and strength. But calcium doesn’t work alone - it requires sufficient protein, vitamin D, vitamin K2, sodium, and magnesium to be properly absorbed, transported, and incorporated into the bone matrix.

Whole-food calcium sources

• Dairy

• Canned salmon or sardines with bones

• Tahini and sesame seeds

• Leafy greens: kale, bok choy, broccoli

3. Vitamin D: The Gatekeeper for Calcium Absorption

Vitamin D allows the gut to absorb calcium effectively. Without adequate vitamin D, even a nutrient-rich diet won’t optimise bone density.

How to get vitamin D

• Sun exposure: 10–20 minutes of midday sun depending on season, skin type, and location.

• Limited food sources:

  • Oily fish such as salmon, sardines, mackerel

  • Egg yolks

Because food sources are minimal, many adults require supplementation based on blood test results and clinical guidance.

4. Vitamin K2: The Unsung Hero of Bone Mineralisation

Vitamin K2 activates osteocalcin - a protein that directs calcium into the bone matrix. Without K2, calcium may circulate without being effectively deposited into bone tissue.

Whole-food vitamin K2 sources

• Natto (the richest source)

• Hard cheeses (gouda, edam)

• Soft cheeses (brie, camembert)

• Egg yolks

• Grass-fed meats

Individuals who avoid dairy and eggs may find it harder to obtain sufficient K2 through food alone.

5. Magnesium: The Mineral That Balances Bone Metabolism

Magnesium is involved in hundreds of biological processes, including vitamin D activation, bone formation, and calcium regulation. Low magnesium levels can impair bone density even if calcium and vitamin D intake are adequate.

Whole-food magnesium sources

• Pumpkin seeds, sunflower seeds, sesame seeds

• Almonds, cashews, Brazil nuts

• Legumes: black beans, lentils, chickpeas

• Leafy greens: spinach, silverbeet

• Avocado

• Berries

• Sardines

• Mineral water

Magnesium content in Australian soils has been depleted over time, meaning many individuals do require supplementation to support their health and wellbeing, and assist in the prevention and management of chronic conditions, such as osteoporosis.

6. Sodium: An Essential Mineral Stored in Bone

Sodium, contained in salt, is frequently misunderstood, but it is essential for human health and plays a meaningful role in skeletal strength. A significant portion of the body’s sodium is stored in bone tissue, where it contributes to overall bone mineral density and serves as a reservoir for maintaining fluid balance, nerve function, and blood pressure regulation.

Putting It All Together: A Whole-Food Approach to Strong Bones

Supporting bone health doesn’t require perfection - just a consistent, well-rounded approach. Here’s an example of what a bone-supportive day might look like:

Breakfast

• Omelette with spinach and cheese cooked in butter

• Greek yoghurt with almonds and berries

• Salt to taste

  
  

Lunch

• Grilled salmon with avocado, leafy greens, pumpkin seeds, and fetta

• Olive-oil and lemon dressing

• Salt to taste

  
  

Dinner

• Stir-fried beef with broccoli, bok choy, and sesame seeds

• Salt to taste

  
  

Snacks

• Cottage cheese with cucumber

• Hard-boiled eggs and a handful of mixed nuts

• Greek yoghurt and berries

  
  

Final Thoughts

Strong bones are built on more than calcium and vitamin D. Protein, magnesium, vitamin K2, and sodium all play critical - and often overlooked - roles in building, maintaining, and protecting the skeletal system. When you bring these nutrients together through whole foods, sensible sun exposure, and balanced eating patterns, you create the foundation for lifelong bone strength and mobility.

In 2026, Tom will be collaborating with the team at Conveniently Active to deliver a unique life-style based program for building strong bones - The Bone Lab. All patients welcome.