HAVANA — Alejandrina Hernández packed only light clothes and a makeup bag when she flew here from Miami this spring. As always, she kept her baggage to a minimum.

Her own baggage, that is.

Ms. Hernández also brought more than 100 pounds of food, clothes and medicine for her family and other Cubans whose relatives in the United States paid her $8 a pound to ferry gifts.

“I need to see my family, but these trips are very expensive,” said Ms. Hernández, who has returned eight times to see her husband and mother in the past 18 months. “This way, I more or less break even.”

Ms. Hernández is part of a surge in Cuban and Cuban-American visitors from the United States since President Obama lifted travel restrictions in 2009 for those with family here.