Calcium is crucial for strong bones and teeth, but it also plays a vital role in blood clotting, muscle contractions, heart rhythm, and nerve function. About 99% of your body’s calcium resides in your bones, while the remaining 1% circulates in your blood, muscles, and other tissues. Maintaining adequate calcium levels is essential for overall health. This article explores the importance of calcium, recommended intakes, health impacts, and – most importantly – answers the question: What Foods For Calcium should you include in your diet?
Understanding Calcium’s Role in the Body
Your body works tirelessly to maintain stable calcium levels in your blood and tissues. When these levels dip too low, parathyroid hormone (PTH) triggers the release of calcium from bones into the bloodstream. PTH also activates vitamin D to enhance calcium absorption in the intestines and signals the kidneys to conserve calcium by reducing its excretion in urine. Conversely, when calcium levels are sufficient, calcitonin lowers blood calcium by inhibiting its release from bones and promoting its excretion through the kidneys.
Your body obtains calcium through dietary sources and by drawing from bone reserves. If your diet lacks calcium-rich foods, your body will borrow calcium from your bones. While this borrowed calcium should ideally be replenished, it doesn’t always happen, potentially leading to long-term bone loss.
top view wooden board with various cheese, nuts, broccoli, canned fish, and jug of milk
How Much Calcium Do You Need?
The Recommended Dietary Allowance (RDA) for calcium varies by age and gender:
- Women (19-50 years): 1,000 mg daily
- Women (51+ years): 1,200 mg daily
- Pregnant and Lactating Women: 1,000 mg daily
- Men (19-70 years): 1,000 mg daily
- Men (71+ years): 1,200 mg daily
Calcium and Your Health: Beyond Strong Bones
While bone health is often associated with calcium, research suggests its impact extends to other areas:
Calcium and Blood Pressure
Studies indicate a possible link between calcium intake and lower blood pressure. However, further research is needed to confirm this connection and establish whether increased calcium intake, beyond the RDA, can effectively treat hypertension.
Calcium and Cardiovascular Disease
Some research raises concerns about calcium supplements and heart health, suggesting a potential link to cardiovascular events. However, current guidelines from the National Osteoporosis Foundation and the American Society for Preventive Cardiology state that calcium from food or supplements, within recommended limits (2,000-2,500 mg daily), has no significant impact on cardiovascular disease in healthy adults.
Calcium and Bone Health
Calcium is fundamental for bone health. Throughout life, bones undergo continuous remodeling, with bone cells called osteoblasts building new bone and osteoclasts breaking down old bone. Adequate calcium intake is vital for maintaining bone density and reducing the risk of osteoporosis, particularly in postmenopausal women.
Calcium and Colorectal Cancer
Observational studies suggest a protective role of high calcium intake against colorectal cancer. While randomized controlled trials using calcium supplements have yielded mixed results, the World Cancer Research Fund and the American Institute for Cancer Research report strong evidence that calcium supplements (over 200 mg daily) and high-calcium dairy foods likely decrease colorectal cancer risk.
Calcium and Kidney Stones
Contrary to previous beliefs, adequate calcium intake from food sources, particularly dairy, may actually reduce the risk of kidney stones. This is thought to be due to calcium’s ability to bind with oxalates in the gut, preventing their absorption and subsequent formation of calcium-oxalate stones. However, calcium supplements may increase the risk of kidney stones.
What Foods for Calcium: Exploring Your Options
Calcium is abundant in various foods beyond dairy. Let’s delve into the best sources:
Dairy Products
Milk, cheese, and yogurt are well-known for their calcium content.
Leafy Green Vegetables
While spinach is high in calcium, its oxalates inhibit absorption. Other leafy greens like kale and collard greens offer better bioavailability.
Fortified Foods
Many foods, including plant-based milk alternatives, juices, and cereals, are fortified with calcium.
Beans and Lentils
These legumes are good sources of calcium and other essential nutrients.
Nuts and Seeds
Almonds, sesame seeds, and chia seeds provide calcium along with healthy fats and fiber.
Fish with Edible Bones
Sardines and canned salmon with bones offer a unique way to boost calcium intake.
Calcium Deficiency and Toxicity
Calcium Deficiency
While true calcium deficiency (hypocalcemia) is rare due to the body’s regulatory mechanisms, long-term inadequate intake can lead to bone loss and osteoporosis.
Calcium Toxicity
Excessive calcium intake (hypercalcemia) can lead to various health issues. The Upper Limit for calcium is 2,500 mg daily for adults under 50 and 2,000 mg daily for those over 50.
Key Takeaways: Answering “What Foods for Calcium?”
A balanced diet rich in calcium-rich foods is essential for overall health. Focus on incorporating a variety of sources, including dairy, leafy greens, fortified foods, beans, nuts, and fish with edible bones. If you have concerns about your calcium intake, consult with a healthcare professional or registered dietitian. They can help you determine the best approach to meet your individual needs. Remember, understanding “what foods for calcium” are best for you is key to a healthier future.
