Publications and Resources. Read the groundbreaking 1977 publication â Phylogenetic structure of the prokaryotic domain: The primary kingdoms ,â by Carl R. Woese and George E. Fox, in which Archaea, the third domain of life, is identified.
Youâre quite right that cod liver oil is a good source of vitamin D. According to the National Institutes of Health, it gives you 1,360 IU per tablespoon (I now recommend 2,000 IU daily). However, at least some kinds of cod liver oil provide as much as 13,500 IU of vitamin A, and thatâs way too much. The Upper Limit of vitamin A set by the Food and Nutrition Board of the National Academy of Sciences is 10,000 IU per day.
Liver damage, however, is a possibility â though only if you were to regularly take a lot of acetaminophen. In people with normal livers, up to 3000mg per day of acetaminophen (that's 9 325mg tablets a day, remember) is incredibly unlikely to cause damage, even if taken daily for weeks or months. For those who worry, it's also fairly easy to check on how the liver is doing with a simple blood test.