Calcium is a micronutrient required for proper formation and maintenance of bones and teeth. Over 99 percent of all the calcium in the body is stored as calcium hydroxyapatite and is found in bones and teeth where it is vital to the strength of these tissues. The remaining calcium circulates in the body and is part of muscle function, nerve signal transmission, signaling, and more. Therefore, dietary calcium intake is important to maintaining not only bone and tooth health but also overall body health.
The recommended daily intakes provided by the National Institutes of Health for adults is around 1,000 mg of calcium per day with higher requirements of up to 1,300 mg per day for children and adolescents. As calcium is so important to proper bodily functioning, it is also important to consider the best sources of dietary calcium. Dairy products provide the richest natural source of calcium, particularly as many milk options are additionally fortified with calcium. For example, a single serving of plain yogurt provides almost half of the daily requirement for calcium.
An important factor to consider when looking for dietary calcium sources is the bioavailability of each source. While non-dairy foods like spinach do contain high levels of calcium on a molecular level, this calcium is not easily accessed by the digestive system. This is because these non-dairy calcium sources contain compounds that bind calcium and limit its digestibility by the body. One such compound is oxalic acid, which is high in spinach, collard greens, and beans. Moreover, studies have also demonstrated that consuming foods high in oxalic acid together with dairy products limits the bioavailability of calcium from the dairy as well.
Are milk and milk products the best source of calcium?
Altogether, dairy products provide the best source of calcium. Milk and other dairy products have been shown to have a positive impact on bone mineral density, no correlation with fractures, and improved dental health, particularly in children and growing adolescents. Studies also noted that while plant-based alternatives may objectively have similar amounts of calcium, there is not enough research to conclude that they have similar bioavailability or positive impact in the body.
In conclusion, milk and dairy products are important for maintaining optimal health. A major component of milk is calcium, which is required for maintaining a strong body infrastructure and for ensuring that bodily functions such as cellular signaling and neuron communication perform adequately.