Although the results are somewhat skewed due to the extensive use of supplements - apart from the MCT oil in the MCT group, all children received an additional mulit vitamin [either Forceval Junior capsules (Unigreg, Morden, UK) or Phlexy-vits powder sachets (SHS International)], the results (cf. figure 1) suggest that, after all, ketogenic dieting cannot be that detrimental to you vitamin and mineral status as one might expect.
|Figure 1: Effects of 12 month on classical or MCT based ketogenic diet on vitamin and mineral status in 49 children.|
(data adapted from Christodoulides. 2011)
It is particularly interesting that while vitamin E increased dramatically in the long-chain fatty acid fed "classical keto" group (no wonder in view of the amount of vitamin E present in most long-chain seed oils), the vitamin A level in that group dropped similarly dramatically.
In comparison, the changes in Zinc, Selenium and Magnesium appear to be negligible. In the case of magnesium the observation that
the pairwise comparison with baseline in children who provided data at both time points showed a significant decrease at 3 and 6 months and a highly significant decrease [of magnesium levels] at 12 monthsespecially in the classical diet is a cause of concern for "those using the diet to treat children with intractable epilepsy", where low(er) magnesium levels appear to correlate with seizures and magnesium supplementation is used as part of the common treatment strategy.
I leave it up to you to decide, whether your think that either a classical or, let alone, a MCT based (with MCTs from supplements instead of whole food sources) diet can be more than a temporary intervention or treatment strategy. Despite the positive evidence that you won't die from mineral insufficiencies or vitamin deficiencies within 12 month of vitamin and mineral supplemented (I assume every keto dieter will take a good multi vitamin anyway) ketogenic dieting, I am still not even remotely considering this to be an option for me.