where does most of the salt we eat come from
Seawater.
Salt
 A major source of salt is seawater, which has a salinity of approximately 3.5%. 
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Salt [SEP] Production
Food-grade salt accounts for only a small part of salt production in industrialized countries (7% in Europe), although worldwide, food uses account for 17.5% of total production. In 2018, total world production of salt was 300 million tonnes, the top six producers being China (68 million), the United States (42 million), India (29 million), Germany (13 million), Canada (13 million) and Australia (12 million). The manufacture of salt is one of the oldest chemical industries. A major source of salt is seawater, which has a salinity of approximately 3.5%. This means that there are about of dissolved salts, predominantly sodium () and chloride () ions, per kilogram (2.2 lbs) of water.