If we have a food supply that we can't trust, that has enormous implications for the way we view government, for the way we trust business, and for our international trade relations.

Unbelievable as it may seem, one-third of all vegetables consumed in the United States come from just three sources: french fries, potato chips, and iceberg lettuce.

What we know about diets hasn't changed. It still makes sense to eat lots of fruits and vegetables, balance calories from other foods, and keep calories under control. That, however, does not make front-page news.

We don't have a farm-to-table food safety system. I keep saying this. It came as a big surprise to the FDA that tomatoes were being grown in the United States, sent to Mexico for packing, and then sent back. I mean, they had no idea that our food chain worked like this.

There are loopholes big enough to drive trucks through. And Congress needs to take a look at those laws and make sure that they're much more rigorous.

Food safety oversight is largely, but not exclusively, divided between two agencies, the FDA and the USDA. The USDA mostly oversees meat and poultry; the FDA mostly handles everything else, including pet food and animal feed. Although this division of responsibility means that the FDA is responsible for 80% of the food supply, it only gets 20% of the federal budget for this purpose. In contrast, the USDA gets 80% of the budget for 20% of the foods. This uneven distribution is the result of a little history and a lot of politics.

What it requires is that first of all you identify the hazards: Where in your production chain can contamination occur? This could be a simple matter of cooking a product to kill bacteria and making sure that the product is actually brought to that temperature.