What do astronauts absolutely need to eat?

Astronauts need a balanced diet that provides essential nutrients to maintain their health and energy levels in space. This includes carbohydrates for energy, proteins for muscle maintenance, fats for overall health, vitamins, and minerals to support immune function. They often consume specially prepared, shelf-stable foods that ensure safety and nutrition, such as freeze-dried fruits, packaged meals, and rehydratable soups. Hydration is also crucial, so they need ample water, often provided through a recycling system on the spacecraft.