These days, the immunity section of Ritzman Natural Health Pharmacy never gets a moment of peace. “It’s an active section year-round,” says Janine Black, retail operations manager for the nine-store chain in Ohio. “Sure, you get a spike during a bad cold and flu season, but it’s never a quiet section.”

Consumers are becoming more proactive about their health, which has turned immunity supplements into a popular category throughout the year. “Most of us have been trained to wait until we’re sick and then do something,” says Gary Kracoff, ND, registered pharmacist for Johnson Compounding and Wellness Center in Waltham, Mass. Now his customers ask how to fend off bugs before they attack. “We’re getting more of those questions, which is great because it’s easier to help a person stay healthy rather than get healthy,” he says.

Fueled by consumer demand for continual protection against sickness, along with new research support for natural options, U.S. consumer sales of cold and immunity supplements climbed to nearly $2 billion in 2010—a 1 percent gain over 2009, according to Nutrition Business Journal.

Although cold and immunity supplements sales remained healthy in 2010, their growth paled in comparison to the 7 percent rise in 2009 and 10 percent expansion in 2008.  “H1N1 gave immunity supplements a very meaningful boost in 2009 and 2008,” says Marc Brush, editor-in-chief of Nutrition Business Journal. “As those sales leave the data set, it makes sense that growth rates slow.”

The H1N1 flu scare may be over, but the sales trajectory of immune supplements remains upward, as new science-backed ingredients emerge and old standbys continue to bolster the category.

What should you stock in your immune-support section? Here are nine brand picks in three product categories that could help drive sales all year long.