What factor might improve the body's absorption efficiency of calcium when mustard greens are cooked versus raw?

Breakdown of the plant structure

While cooking can sometimes degrade certain heat-sensitive nutrients, such as Vitamin C, the application of heat to leafy greens like mustard greens can positively influence the absorption of certain minerals, particularly calcium. The structure of plant cells is composed of rigid cell walls, and heat processing helps to break down this tough matrix. This mechanical breakdown liberates the mineral content, making it more accessible for the digestive enzymes and absorption sites in the small intestine. Some studies suggest this structural degradation leads to a slightly more efficient uptake of calcium compared to when the vegetable is consumed entirely raw. It is important to contrast this with the effect of oxalic acid, which is present in some greens and known to actively inhibit or bind to calcium, thereby potentially reducing absorption, regardless of cooking method.