KATHMANDU: Maintaining bone health is essential for overall well-being, particularly as we age. Bones provide structural support, protect vital organs, store and release minerals, and facilitate movement.

Strong, healthy bones are key to an active, disease-free life. One of the most effective ways to support bone health is through a calcium-rich diet. Calcium is the most abundant mineral in the body, with about 99% stored in the bones and teeth, playing a vital role in their strength and function.

In this article, we’ll explore calcium’s role in bone health, recommended daily intake at various life stages, dietary sources of calcium, and tips to maximize calcium absorption.

How Much Calcium Do You Need?

Calcium requirements vary depending on age, sex, and life stage. According to the National Institutes of Health (NIH), the recommended daily intake is:

• Infants (0–6 months): 200 mg
• Infants (7–12 months): 260 mg
• Children (1–3 years): 700 mg
• Children (4–8 years): 1,000 mg
• Children (9–18 years): 1,300 mg
• Adults (19–50 years): 1,000 mg
• Women (51+ years): 1,200 mg
• Men (51–70 years): 1,000 mg
• Men (71+ years): 1,200 mg
• Pregnant and breastfeeding women:
  • Under 19 years: 1,300 mg
  • 19 years and older: 1,000 mg

These figures reflect the body’s changing calcium needs at different stages of life.

Why Is Calcium Important for Bone Health?

• Bone Density and Formation: Calcium is a fundamental component of bone tissue. It is especially crucial during the growth years—from childhood to early adulthood—when bone mass is being built.
• Bone Strength: Calcium supports bone structure and density, reducing the risk of fractures and conditions such as osteopenia and osteoporosis.
• Hormonal Regulation: Calcium helps regulate hormones that affect bone health. The body maintains stable calcium levels in the blood to support muscle contractions, nerve signals, and blood clotting. When dietary calcium is low, the body pulls calcium from bones, weakening them over time.
• Bone Remodeling: Bones are continuously renewed through remodeling—a process where old bone is replaced with new tissue. Calcium is essential to maintain bone integrity during this cycle.

Dietary Sources of Calcium

Here are some excellent calcium-rich foods:

• Dairy Products: Milk, yogurt, and cheese are top sources. One cup of milk typically provides around 300 mg of calcium.
• Leafy Green Vegetables: Greens like mustard greens (rayo) and broccoli are good plant-based sources.
• Nuts and Seeds: Almonds, chia seeds, and sesame seeds are calcium-rich. One ounce of almonds contains about 76 mg of calcium.
• Beans and Lentils: Varieties such as white beans, navy beans, and black beans are calcium sources. A cup of cooked white beans contains around 160 mg.
• Fruits: Fruits like oranges and blackberries offer small amounts of calcium. For example, a medium orange has approximately 60 mg.
• Fortified Foods: Many plant-based products are calcium-fortified, such as soy milk, almond milk, oat milk, and orange juice.
• Fish with Edible Bones: Sardines and canned salmon provide calcium when eaten with bones. A 3-ounce serving of sardines contains about 325 mg.
• Tofu and Tempeh: Especially when prepared with calcium sulfate, tofu can offer 200–400 mg of calcium in just 4 ounces.

Tips to Boost Calcium Absorption

• Vitamin D: Essential for calcium absorption. Sources include fatty fish, egg yolks, and fortified foods. Sunlight exposure also stimulates vitamin D production in the skin.
• Limit Sodium: High sodium intake can increase calcium loss through urine.
• Moderate Caffeine and Soda: Excessive caffeine and phosphoric acid (in sodas) can hinder calcium absorption and increase calcium excretion.
• Balanced Diet: A diet rich in fruits, vegetables, whole grains, and healthy fats can support overall calcium metabolism.

Calcium Supplements: When Are They Needed?

Food should be your primary calcium source, but some individuals may require supplements—especially those with dietary restrictions like vegans. Always consult a doctor before starting supplements to determine the right dosage. Excessive calcium intake, particularly through supplements, can cause kidney stones, constipation, and other issues.

• Upper Intake Limits:
  • Adults under 50: 2,500 mg/day
  • Adults over 50: 2,000 mg/day

Other Lifestyle Factors That Support Bone Health

• Regular Exercise: Weight-bearing and resistance exercises, such as walking and lifting weights, strengthen bones and improve balance.
• Quit Smoking: Smoking reduces bone density and increases the risk of fractures.
• Limit Alcohol: Excessive alcohol weakens bones; moderate consumption helps maintain bone strength.

Conclusion

Maintaining strong bones requires a lifelong commitment to healthy eating and lifestyle habits. A calcium-rich diet—incorporating dairy, leafy greens, fortified foods, and fish—plays a foundational role. Additionally, ensuring sufficient vitamin D intake, engaging in regular weight-bearing exercises, and avoiding harmful habits like smoking and heavy drinking are all critical to preserving bone health over time.