I have to backtrack a little. Several weeks ago I suggested using olive oil as a spread for bread instead of butter (high in saturated fat) or margarine (high in trans-fatty acids), because it's a healthier kind of fat.
I'll stand by that recommendation, but with some caveats.
One is to limit the quantity you use, because eating too much fat of any kind increases the likelihood of unnecessary weight gain, as well as increasing your risks for some kinds of cancer.
The second is to be very careful if you're inclined to prefer garlic in your oil. Several years ago the Food and Drug Administration (FDA) found commercially prepared chopped garlic-in-oil to be the cause of two outbreaks of botulism -- a type of food poisoning historically associated with foods improperly canned at home, but more recently with various soil-grown vegetables.
Botulism is quite virulent, causing blurred vision, paralysis, speech and breathing difficulty and even death when not treated promptly. Its tough and resistant spores are found in soil, so any vegetable that grows down in the dirt can carry a few. But the organisms require a special circumstances to grow and multiply enough to make you sick.
They need both an oxygen-free environment (provided by smothering the garlic in oil), and several hours at room temperature.
The FDA solved the grocery store problem of garlic-in-oil by requiringmanufacturers to add an anti-microbial agent (citric acid phosphoric acid), and a warning to refrigerate after opening. Heed that warning and you'll be OK.
But be especially careful if you make your own garlic-flavored oil or find it in a restaurant where it contains no anti-microbial ingredient.
Robert E. Harrington, assistant director of technical services for public health and safety of the National Restaurant Association, warns, "Although the FDA did not directly address the hazards of garlic-in-oil prepared on-premises, there is the same potential for outgrowth."
He further recommends that restaurants guard against this hazard by limiting the time that garlic-in-oil mixtures stand at room temperature to "no more than a few hours."
Mr. Harrington says, "Probably the best advice is to discard such mixtures after a single meal setting, thoroughly wash, rinse and sanitize the containers, and do not "marry" newly prepared stock with leftovers."
You may want to check into this policy at your favorite restaurant, and follow the same rules at home.
Colleen Pierre, a registered dietitian, is the nutrition consultant to the Union Memorial Sports Medicine Center in Baltimore.