Final answer:
Table salt, or sodium chloride, is the major dietary source of chloride, essential for digestive and cellular functions.
Step-by-step explanation:
The major chloride source in the diet is table salt. This substance, also known as sodium chloride (NaCl), is a critical element of our diet that provides chloride for the production of hydrochloric acid in the stomach and helps in cell membrane transport. While other foods, such as aged cheese, roasted nuts, and low fat milk, do contribute to our chloride intake, none are as significant a source as table salt. Moreover, it's worth noting that chloride is abundantly available through table salt added to processed foods, ensuring that most diets provide plenty of this essential nutrient.