As of May 1, 2010, the Cuban authorities require travel insurance with coverage for medical expenses to enter the country.
When traveling to Cuba you can purchase insurance of this type in your country of origin, prior to the trip, or you can purchase it upon arrival in Cuba, at the point of entry into the country.

The visitor must have a valid passport or a travel document issued in their name and the corresponding visa or Tourist Card. The countries with which Cuba maintains free visa agreements are excepted. The Tourist Cards can be requested before the Cuban consular representations. Also, in travel agencies and airlines. They are of two types: for individual tourists or for tourists traveling in a group.

Yes, you may pack food in your carry-on or checked bag, but remember all food must undergo x-ray screening. Foods that are liquids, gels, or aerosols must comply with the 3-1-1 liquids rule.