Technologies
Producing intravenous fluid from water could allow not having to carry this medical supply. A prototype for this concept was tested on the International Space Station in 2010.
Space bread has proved elusive because of a variety of challenges. By 2012 a method was suggested where dough is leavened by dissolved CO2 (as opposed to yeast) and cooked by a low temperature process. This could allow fresh baked bread from bulk ingredients on future spaceflights.
Mars habitats may use 40% Argon, 40% Nitrogen, and 20% Oxygen. Nitrogen and Argon can be taken from Mars air but are hard to separate from each other.
Read more about this topic: Manned Mission To Mars