Most people don't think of fruits and vegetables as being hazardous to their health. We tell our kids to eat their leafy greens and juicy fruits so they can grow up to be healthy and strong. But did you know that the "healthiest" foods are on the list of the 10 riskiest foods to eat in the U.S.?

A recent report published by the Center for Science in the Public Interest (CSPI) using data from the Centers for Disease Control and Prevention, state health department and federal government publications, found that leafy greens (including lettuce and spinach), tomatoes, sprouts and berries are among the top 10 riskiest FDA-regulated foods in the U.S. Other foods on this list include eggs, tuna, oysters, potatoes, cheese, and ice cream. (Beef and poultry were not included in the study as they are monitored by the Department of Agriculture.)

Why are they risky?

The short answer is "foodborne illnesses." The researchers found that the top cause of illness were pathogens such as E. coli, Norovirus and Salmonella.

The study, which looked at 16 years of data on food outbreaks (1990-2006), found that more than 1,500 separate outbreaks were associated with these top 10 riskiest foods, causing nearly 50,000 reported illnesses, ranging from temporary gastrointestinal distress to long-term disability and death.

Here is the breakdown of reported cases:

  • Leafy greens, 363 outbreaks, 13,568 illnesses
  • Eggs, 352 outbreaks, 11,163 illnesses
  • Tuna, 268 outbreaks, 2,341 illnesses
  • Oysters, 132 outbreaks, 3,409 illnesses
  • Potatoes, 108 outbreaks, 3,659 illnesses
  • Cheese, 83 outbreaks, 2,761 illnesses
  • Ice cream, 74 outbreaks, 2,594 illnesses
  • Tomatoes, 31 outbreaks, 3,292 illnesses
  • Sprouts, 31 outbreaks, 2,022 illnesses
  • Berries, 25 outbreaks, 3,397 illnesses

The study indicated that most foodborne illnesses don't get treated or reported, so the real total for each food listed is likely much larger.

And the culprits of these foodborne illnesses?

  • Contaminated irrigation water
  • Manure
  • Inadequate storage
  • Improper handling of food
  • Improper preparation and cooking practices

Here's a look at the 10 riskiest foods, why they are risky, and some tips to help you reduce possible exposure to foodborne illness.

Leafy greens. Many of the leafy green outbreaks were associated with eating bagged, pre-washed greens. Bagged greens are more processed and handled and because of this, might have a higher risk of contamination. Greens as a whole, grow close to the ground, and therefore are more susceptible to pathogens due to contaminated irrigation water, manure, and unsafe handling practices.

Eggs. Eggs can be contaminated with salmonella both on the outside and inside of the egg. Cooking your egg thoroughly is the best way to protect yourself.

Tuna. The type of tuna largely associated with outbreaks was fresh or raw tuna. Unfortunately, the type of contaminant found in tuna cannot be cooked away.  Do be sure that the tuna you eat comes from reputable source. Most fish contamination occurs when the fish is left in warm temperatures for too long.

Oysters. Most reported oyster outbreaks tended to occur from restaurants where poor food handling was the culprit. You'll have to weigh the pros and cons of eating oysters.

Potatoes. The potato is on the list because of the ingredients its associated with-- mayonnaise and sour cream. The potato is also more susceptible because it is in close contact with the soil and therefore is at higher risk. Scrub your potatoes well and don't leave potato salad out for longer than two hours.

Cheese. Making cheese requires several steps (curdling, salting, processing); therefore there are more opportunities for contamination.

Ice Cream. The outbreaks with ice cream were linked to using contaminated eggs and unsafe food handling practices.

Tomatoes. Because tomatoes are frequently eaten raw, and usually come into contact with soil, they also have a higher risk of carrying pathogens. Washing tomatoes well and using separate cutting boards for produce and raw meat will help to minimize risk.

Sprouts. Some say we should completely avoid eating sprouts like alfalfa or mung bean sprouts because the "seed" houses the contaminant, and therefore no amount of rinsing can remove the problem.

Berries. The largest outbreak with berries (strawberries) occurred in 1997, but all berries carry risk of foodborne illness. Wash all of your berries thoroughly.

How to identify if you have a foodborne illness:

Symptoms of a foodborne illness typically are experienced within six hours of eating tainted food, though it may be longer. The symptoms vary according to the source of contamination but generally include diarrhea, nausea, abdominal pain, and sometimes vomiting.

What to do if you think you have a foodborne illness:

If you develop symptoms of a foodborne illness, doctors recommend resting and drinking plenty of fluids. Taking anti-diarrheal medications is not advised because they may slow elimination of bacteria from your system.

Foodborne illness often improves on its own within 48 hours, according to the Mayo Clinic. However, if you feel ill for longer than two or three days, or if blood appears in your stools, contact your doctor.

Sources

Center for Science in the Public Interest. Leafy Greens, Eggs & Tuna Top List of Riskiest FDA-Regulated Foods. Washington, DC. October 6, 2009.

Website: http://www.cspinet.org/new/200910061.html

Family Health Watch: Local News. Study Lists 10 riskiest FDA-regulated Foods That Could Make us Sick. KY3News. October 7, 2009.

Klein, S., Witmer, J,, Tian, A., and C.S. Dawall. Center for Science in the Public Interest. The Ten Riskiest Foods Regulated by the U.S. Food and Drug Administration. Washington, DC. October 2009.

Website: http:// www.cspinet.org

Food-borne Illness Information Page. MayoClinic.org. http://www.mayoclinic.com/health/first-aid-food-borne-illness/FA00043

Scott, J. Take Care to Prevent Foodborne Illnesses. Oregon State University News Service. February 25, 2009.

United States Department of Agriculture, Food Safety and Inspection Service. Safe Food Handling Fact Sheet. June 2006.

Website: http://www.fsis.usda.gov/Factsheets