Page 105 of the Stephen Sheffrey, D.D.S. book:
Steven Sheffrey wrote:......As mentioned, bioflavonoids aid in the absorption and utilization of C. [More is also absorbed from a C solution that is sipped slowly but the acid form will etch tooth enamel. Long-term use of the method is not advised.] Bioflavonoids are flavonoids the body can use. The trend is toward omitting "bio" and just calling them flavonoids. Some are powerful antioxidants. Some help prevent heart disease (Note 31). Some were once called vitamin P but the term was considered inappropriate by 1950.
......Plants differ in the type of flavonoid produced. Vitamin C extracted from plants in the 1930s contained about 2.5% impurities, probably including flavonoids. The impure C was more than twice as effective as synthetic C in preventing paralysis and death of monkeys infected with poliomyelitis (Note 32). The early belief that natural C is better than the synthetic product probably stemmed from that report. We can return our C to the "impure" state by taking it with added flavonoids or with fruits and vegetables. Citrus flavonoids appear to work well with C.
......Consider this 1937 report by two physicians, one a professor, at a university clinic in Copenhagen: Before synthetic C was available they cured scurvy with the juice of 5 to 10 lemons a day for a week or more. They switched to synthetic C after it became plentiful, giving 300 mg a day, the amount in the juice of 10 lemons. The synthetic C readily cured 26 of 29 patients---but had no effect on the other 3, not even when given intravenously! The 300 mg of injected C, equal to 600 mg of oral C, was in the bloodstream, available to the body but of no value because it could not be utilized. It even failed to raise the plasma C to normal. To achieve a cure it was necessary to give the patients lemon juice (Note 33). A look at the case histories of the 3 patients is of interest:
Vitamin C: how best to use it: how improper clinical trials have misled us!: separating fact from fiction to ensure proper use / Stephen Sheffrey, D.D.S. -- 2nd ed. (2002)
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