Want to make sure you get those discounts on canned peaches without Big Brother tracking every move in Aisle 6? Some ways to ensure your privacy when using loyalty cards, according to privacy experts:

• Withhold as much information as possible, from your license plate number to income. In many cases, it’s not necessary for shoppers to supply name and address to get a loyalty card and take advantage of the weekly discount offers. But they won’t be able to receive extra coupons and other information in the mail based on what they buy. Read the application carefully to find out the options.
• Use cash. Even if you didn’t use your name to get the card, using a credit card or writing a check immediately links your past and future purchases to your name, according to Katherine Albrecht, founder and director of Consumers Against Supermarket Privacy Invasion and Numbering.
• Find out whether the store has a stated privacy policy by checking the back of the card, the application or signs. Some stores have vague policies, so customers need to ask a manager or an executive if the data is being sold to manufacturers and marketing firms. Privacy expert Larry Ponemon said he is worried that data like weekly alcohol purchases could be used against consumers in such areas as divorce and custody battles.
• Find out who in the company has access to the buying information. Is the data readily accessible by sales staff members and sloppily managed?