The Essential Role of Calcium in Bone Health and Athletic Performance
Today, I want to go deeper into the crucial mineral that often gets overshadowed by the trendier nutrients in the spotlight: calcium. While many might only associate calcium with building strong bones, its significance stretches far beyond that, particularly for those of us dedicated to athletic performance and overall health.
Why Calcium Matters for Your Bones and Beyond at All Ages
First things first—calcium is the cornerstone of healthy bones and teeth. About 99% of the calcium in our bodies is stored in our bones and teeth. The remaining 1% (small but significant) plays a vital role in various bodily functions, including muscle contraction, blood clotting, and nerve transmission.
For athletes and active individuals, maintaining strong bones is paramount. While weight-bearing exercise is indeed helpful to building strong bones, the repetitive stress exerted during high-intensity workouts or endurance training can lead to stress fractures or osteopenia/osteoporosis if calcium intake is consistently inadequate. More than 95% of the adult skeleton is formed by the end of adolescents with peak bone mass being reached by age 30.
But here’s a crucial point: ensuring adequate calcium intake isn’t just about preventing bone injuries; it’s about optimizing performance. And while strong bones support stronger muscles and better endurance there are other important factors to consider:
- Calcium is essential for muscle contractions, including the smooth functioning of the heart muscle. It helps in transmitting nerve signals that control muscle contractions, which contribute to muscle performance and strength.
- Some studies suggest that calcium may aid in weight management by potentially reducing fat absorption in the gut. Higher calcium intake has been associated with lower body weight and a better ability to maintain a healthy weight.
- Calcium plays a role in various metabolic processes, including hormone secretion, enzyme activation, and energy metabolism. Appropriate calcium intake can help support overall metabolic health and energy production.
- Adequate calcium intake is linked to a reduced risk of hypertension and cardiovascular diseases. Calcium helps in regulating blood pressure, supporting healthy blood vessels, and improving overall heart function.
- Calcium is involved in the release of neurotransmitters, which are essential for communication between nerve cells. Optimal calcium levels are necessary for cognitive function, memory, and mood regulation.
The Misleading Nature of Calcium Blood Markers
One common misconception I want to address is the reliance on blood markers to assess calcium levels. Many people assume that if their blood calcium levels are normal, their dietary intake of calcium must be sufficient. However, this is a dangerous thought process.
Our bodies are incredibly adept at maintaining stable blood calcium levels — at the expense of our bone health. When dietary calcium is insufficient, our body will pull calcium from our bones (the body’s largest store) to keep blood levels stable, leading to weakened bones over time. This means you can have normal blood calcium levels while your bones are silently suffering from a lack of this essential mineral.
Calcium’s Role in Preventing Kidney Stones
Another important, yet often overlooked, aspect of calcium intake that I think is worth mentioning is its role in the prevention of kidney stones. Contrary to popular belief, higher dietary calcium intake can actually reduce the risk of kidney stones, not increase it. When you consume adequate calcium, it binds to oxalates (compounds found in certain foods) in the intestines, preventing them from being absorbed into the bloodstream and later forming stones in the kidneys.
Adequate and consistent fluid intake is, of course, the biggest prevention tool for preventing kidney stones, but calcium is worth the mention based on the uninformed and potentially harmful dietary recommendations that athletes receive when dealing with kidney stones.
It’s important to differentiate between dietary calcium and calcium supplements. While dietary calcium (from food sources like dairy, leafy greens, and fortified products) has protective effects against kidney stones, excessive calcium supplementation can contribute to stone formation. Therefore, aim to get your calcium primarily from a balanced diet.
Getting Enough Calcium: Tips and Recommendations
In the US, the recommended daily calcium intake ranges from 1,000mg-1,300mg for adults depending on your age and gender.
So, how can you ensure you’re getting enough calcium? Here are some practical tips:
- Choose 3 Calcium-Rich foods each day (one per meal): When reading a nutrition label, look at the % DV of calcium. 20% or greater (per serving) is an “excellent” source so choose these most often. 10-19% DV represents a “good” source and can also be the calcium selection for your meals. Any food with a DV of less than 10% should be thought of as bonus foods for your calcium intake and paired with other foods or added to snacks to bump your intake.
Dairy products are well-known as the best sources of calcium. However, if you don’t do dairy there is good news — most of the plant-based dairy alternatives are now fortified with calcium. Be sure to check the nutrition facts.
Other sources, mostly in the good or bonus category are leafy green vegetables (like collard greens, bok choy, kale), chia seeds, tofu, soybeans and canned fish with bones.
- Monitor Vitamin D: Vitamin D3 (25-OH) enhances calcium absorption, so make sure you’re getting enough of this vital vitamin through sun exposure, diet, or supplements. Blood markers are useful for Vitamin D, so have your levels checked at least once a year.
Calcium is a non-negotiable nutrient for anyone aiming to maintain peak physical health and performance. Don’t be misled by blood markers—ensure your dietary intake is sufficient to support your bones, muscle contractions, metabolism and overall health. By remembering to choose a calcium-rich food at each meal, you’re not just protecting a strong skeletal foundation, you are also supporting your athletic performance and longevity.