Some people are more likely than others to get sick from harmful bacteria that can be found in food. And once they are sick, they face the risk of more serious health problems, even death.

Seniors are more susceptible to food borne illness because the immune system weakens as we age. In addition, stomach acid also decreases as we get older - and stomach acid plays an important role in reducing the number of bacteria in our intestinal tracts - and the risk of illness. Plus underlying illnesses such as diabetes, some cancer treatments and kidney disease may increase a person's risk of food borne illness.

It can be difficult to recognize when harmful bacteria in food have made them sick. For instance, it is difficult to tell if food is unsafe, because you cannot see, smell or taste the bacteria it may contain.

Oftentimes people think their food borne illness was caused by their last meal. In fact, there is a wide range of time between eating food with harmful bacteria and the onset of illness. Usually food borne bacteria take one to three days to cause illness. But you could become sick anytime from 20 minutes to six weeks after eating some foods with dangerous bacteria. It depends on a variety of factors, including the type of bacteria in the food.

If you get food borne illness, you might be sick to your stomach, vomit, or have diarrhea. Or, symptoms could be flu-like with a fever and headache and body aches. The best thing to do is check with your doctor. And if you become ill after eating out, also call your local health department so they can investigate.

Food borne illness can be dangerous, but is often easy to prevent. By following four basic rules of food safety: Clean, Separate, Cook and Chill, you can help prevent food borne illness for yourself and others.