Vitamin C bioavailability
According to the review Synthetic or Food-Derived Vitamin C—Are They Equally Bioavailable? (Nutrients, 2013), the bioavailability of vitamin C from foods and supplements is similar:
...all steady state comparative bioavailability studies in humans have
shown no differences between synthetic and natural vitamin C,
LDL has the higher protein content than HDL. LDL consists of Apo B48 and Apo B100. These are proteins with higher molecular weights between 250 kDa to 550 kDa as compared to other apoproteins. And these apoproteins are not present in HDL.
And if lipoprotein (a) is included in comparison then it has highest protein content.