Scurvy on a diet devoid or nearly devoid of vitamin C, had blood levels of vitamin C too low to be accurately measured when they developed signs of scurvy, and in the Iowa study, at this time were estimated (by labeled vitamin C dilution) to have a body pool of less than 300 mg, with daily turnover of only 2.5 mg/day. The vast majority of animals and plants are able to synthesize vitamin C, through a sequence of enzyme-driven steps, which convert monosaccharides to vitamin C. However, some mammals have lost the ability to synthesize vitamin C, notably simians and tarsiers.
Vitamin E are needed to compensate for the lack of α-TTP Vitamin E deficiency due to either malabsorption or metabolic anomaly can cause nerve problems due to poor conduction of electrical impulses along nerves due to changes in nerve membrane structure and function. In addition to ataxia, vitamin E deficiency can cause peripheral neuropathy, myopathies, retinopathy and impairment of immune responses. In the United States vitamin E supplement use by female health professionals was 16.1% in 1986, 46.2% in 1998, 44.3% in 2002, but decreased to 19.8% in 2006. Similarly, for male health professionals, rates for same years were 18.9%, 52.0%, 49.4%