Is that salad safe to eat? How to keep germs, bacteria out of your leafy greens

PHILADELPHIA (WPVI) -- A big green, crisp salad is a healthy diet staple, but it doesn't come without risks.

You've probably noticed within the last decade, the Centers for Disease Control and Prevention reported nearly 80 foodborne disease outbreaks linked to leafy greens.

Consumer Reports' food experts say don't give up lettuce, just take a few extra precautions.

Most recent romaine lettuce recalls are linked to E. coli and listeria.

Why and how? That's tricky to answer. Contamination can happen anywhere from farm to table. Cattle can carry deadly strains of E. coli. Their manure that has the bacteria can seep into irrigation water and contaminate crops.

No single type of leafy green is risk-free, but hydroponic lettuces, which are greenhouse-grown without soil, are less likely to be contaminated by bacteria from animal droppings.

Even when leafy greens are grown free of harmful bacteria, contamination can still occur during harvesting, processing, or packaging. That's why it's so important you take extra steps to protect yourself.

Whole heads of lettuce instead of bagged greens might be safer. Whole heads don't necessarily have lower bacteria levels, but their inner leaves are less exposed to sources of contamination and are handled less than bagged greens.

Refrigerate bagged lettuce right after you buy it. It won't prevent foodborne illness, but will slow spoilage.

Buy packages with expiration dates as far in the future as possible and don't buy more than you can eat in a few days.

Another strategy is to opt for leafy greens that can be cooked, like spinach or kale because the heat will kill bacteria.

This is particularly important for people who are more susceptible to the ill effects of food poisoning, such as those who are immunocompromised, pregnant, or elderly.