Final answer:
Excessive intakes of phytates and oxalates interfere with the absorption of minerals such as calcium, phosphorus, and iron by forming insoluble compounds that the body cannot absorb effectively.
Step-by-step explanation:
Excessive intakes of phytates and oxalates can interfere with the absorption of minerals. These substances bind to minerals such as calcium, phosphorus, and iron in the intestines, forming insoluble compounds that cannot be absorbed. For example, oxalate can bond with calcium to form calcium oxalate, which precipitates in the intestine and reduces calcium absorption. Similarly, phytic acid from foods can bind with calcium and other minerals, reducing their bioavailability.
Moreover, excess iron can affect calcium and phosphorus absorption by forming insoluble ferric phosphate. Dietary factors like phytates, oxalates, high phosphate, and fibre can thus negatively impact mineral absorption and upset the Ca:P ratio. In contrast, dietary lipids can aid the absorption of certain minerals.