everyday chemistry - Which side of an aluminum foil should I put in contact with food?

Aluminum foil has two sides: a matte one, and a shiny one.
My question is: which one should I put in contact with food?

Criteria are lowest risk of toxicity and best qualities for food preservation (e.g. do not favor oxidizing, or react with acid nor alkaline ingredients)

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For information, I've come across these several explanations; they are however contradictory (and might not be accurate):

• Both side have same properties. The difference in terms of appearance is only due to the manufacturing process. (Two foils are laminated at the same time, so each foil is in contact with the rolls on one side only — hence the asymmetrical look).
  In this case, we can use both side of the foil.


• Aluminum foil is actually made of two layers: one of aluminum, another that is coating. The surface of the aluminum layer that is in contact with atmosphere oxidizes and turns into aluminum oxide — hence the matte side.
  In that case, we should use the shiny side, since aluminum oxide is not that healthy.