Next time you walk up and down the aisles of the grocery store, look at the thousands of different food and beverage products on every shelf and in every freezer and ask yourself how – or even if – you could come up with a rational system for declaring a food “good” or “bad” or “healthy” and “unhealthy.”

Obviously, many foods would be easy to classify; fruits and vegetables are good and healthy.

But what about meat? Thirty percent fat ground beef is high in protein. However, a three-ounce serving packs as much as 25 grams of fat. So would you call it “bad?” How about “unhealthy.” Would you tell people they can’t purchase 30 percent fat ground beef?

You probably don’t eat much beef liver, if at all, and while you might label it “bad” you probably wouldn’t label it “unhealthy.” However, for all the healthy iron, protein and vitamins in beef liver, it also contains high levels of Vitamin A, which can be dangerous if consumed in large quantities. Eat three-ounces of beef liver and you’ll get nearly twice the daily maximum amount of Vitamin A recommended.  You’ll also consume an entire day’s worth of cholesterol.

And that brings us to the egg. A decade or two ago, we were told to avoid eating eggs on a regular basis because of the cholesterol in yolks. Today, we’re told eating an egg a day is just fine because they contain less cholesterol than 10 years ago. So should we, or shouldn’t we, eat eggs and are they healthy or unhealthy? An article on the Mayo Clinic website advises, “Although eating too many eggs can increase your cholesterol, eating four egg yolks or fewer on a weekly basis hasn't been found to increase your risk of heart disease.” Clear as mud.

That lack of clarity and rational is why the USDA, which administers the federal food stamp program known as SNAP, has declined requests from states like Minnesota to limit the foods allowable for purchase with food stamps.

Simply put, “Federal dietary guidance uniformly applies to the total diet – there are no widely accepted standards to judge the ‘healthfulness’ of individual foods.”

South Carolina Governor Nikki Haley announced plans today to improve the health of low-income South Carolinians by asking the USDA to allow the state to limit the foods and beverages that poor people on food stamps are allowed to purchase in her state. The governor only wants these people to purchase “healthy” foods. She didn’t say whether or not South Carolina would put eggs on the “Do Not Purchase” list.

It’s worth noting that according to government reports, the purchasing habits of people on food stamps are “nearly identical” to those not on assistance. In other words, most Americans need to improve their diets – not just people with low or no incomes.

Finally, the USDA resists the process of characterizing more than 300,000 food items in grocery stores today, along with the 15,000 new foods each year, because doing so would increase program cost and complexity.

The USDA plays the important role of regulating food safety and inspection. Taking their focus off public health and forcing them down the slippery slope of picking and choosing what people should or shouldn’t put in their grocery carts is bad public policy.