Q: I heard that canned foods can cause food poisoning in pregnant women. Is it true?

A: Pregnant women are more susceptible to food poisoning. Canned foods if not closed or jarred properly can harbor bacteria, and lead to botulism and other bacterial diseases. Canned foods are heated to an extreme temperature to process them and kill micro-organisms before canning. This destroys most enzymes and nutrients in them, so they are almost like junk foods — a slow poison.

Moreover, canned foods including canned fruits, vegetables and soda contain a compound that can possibly cause birth defects. This compound is the BPA or bisphenol A, a toxic substance in the plastics and epoxy resins that line food cans. If pregnant women eat just a single serving of canned food they will be exposed to unsafe levels of BPA. Canned pasta, soup and infant formula have the highest BPA levels. BPA can cause cancer, fertility problems, heart diseases and liver ailments in pregnant women.

It is better to eat fresh or frozen food or eat food from glass jars. Alternatively, you can seek out canned food where a non-BPA method is used for lining cans. Rinsing canned fruits and vegetables before consumption may reduce the risk.

Recently pregnant women have been warned against eating canned tuna and tuna salad as these canned foods have very high levels of mercury in them that is highly poisonous. Canned tuna was found to have as much mercury as white tuna by research studies. When high mercury levels enter your bloodstream it may harm the development of nervous systems of the baby. FDA has advised pregnant women not to have no more than 170 grams of canned tuna per week.

In the end, it's better to avoid canned foods and focus on fresh healthy food while you're pregnant.