In that riveting courtroom scene we all know from the movie A Few Good Men, Jack Nicholson’s character famously tells us: We can’t handle the truth. That often seems the case with regard to food.

I have encountered the resistance to fundamental truths about food often, but I am committed to doing the best I can to tell them even so. I tell them in narrative every chance I get. I tell them to kids. I tell them with numbers. I tell them in song. I would tell them on a boat; I would tell them to a goat.

I care deeply about the truth about food, because this particular truth could set us substantially free from the threat of chronic disease and premature death. Chewing and swallowing the truth about food could add years to our lives, and lives to our years. That’s my mission, and the truth about food is at its very foundation.

And so I was very gratified to find a recent Huffington Post blog post all about NuVal, and telling the blunt truth about the truths we are trying to tell with that nutrition guidance system. The author, Professor Marty Kaplan of USC, entitled his article “Supermarkets Say: Please Don’t Buy the Crap We Sell.” Too blunt, if anything!

Prof. Kaplan went on to point out the many instances in which NuVal — which provides a summative score for overall nutritional quality from 1-100, the higher the number, the more nutritious the food — is surprising. Many products with implied nutritional virtues — such as multigrain crackers, or heavily-fortified breakfast cereals — are quite dubious when nutritional quality is measured objectively and comprehensively. NuVal is, in fact, of greatest use when at its most surprising — because that’s when we need it most. Prof. Kaplan highlighted that very fact.

But, of course, supermarkets aren’t really saying anything about not buying what they sell. Rather, those stores that use NuVal — including Big Y and Price Chopper here in my home state of Connecticut — are committed to providing nutrition guidance as a service to their customers. NuVal doesn’t tell anybody what to buy, any more than GPS tells anybody where to go. Both are intended just to help you get there. Both tell you what’s what, not what to do.

And, since supermarkets sell lots of nutritious food along with a whole lot of junk, if anything NuVal really helps them say: You can trade up if you want. You can find more or less nutritious foods in every aisle — and here they are. Choose as the spirit moves you.

While I am gratified by Prof. Kaplan’s endorsement of truth-telling, I am more often beleaguered by the gripes of those who don’t like it at all. They come in several varieties.

Manufacturers who sell junk food don’t much care for the truth about food being on at-a-glance display. No great surprise that the makers of things like Fluffernutter and Velveeta don’t much care for NuVal. More surprising is that our federal agencies may have reservations, too, if only or mostly because of their entanglements with just such manufacturers.

But the more troubling gripes — including some appended as comments to Prof. Kaplan’s overwhelmingly well-received article — are from the devout friends of better nutrition. Devout friends of public health nutrition, but with very strong opinions.

Some of them think that all sugar substitutes are the worst thing in the food supply. Others think that sugar is, and replacing it with anything is trading up. Others think sodium is the bigger concern. Others think saturated fat is a problem, and others think it’s omega-6 fat. Some think canned pears in heavy syrup qualify as “fruit,” and others think — not so much.

These, and others, invariably manage to find NuVal scores they don’t like. Or, even more commonly, they find score comparisons they don’t like — such as a breakfast cereal that scores higher than, say, lobster. But most such comparisons are ludicrous; who would ever be making a choice between lobster and breakfast cereal anyway? The greatest utility of the system is to inform real-world choices, which are mostly among closely related items on the same supermarket shelf.

Most scores, and score comparisons, people don’t like are simply at odds with their personal priorities. NuVal, in contrast, is a product of the best available science and the consensus judgment of a diverse team of renowned scientists. It does not represent anyone’s opinion.

Sometimes, the scores that are challenged deserve to be revisited. This can be because of inaccuracies in nutrition fact panel data or ingredients, evolving nutrition science, or changes in the operational capacity of NuVal itself. To that end, a process of constant quality control is in place, and scores are routinely updated — as is the scoring algorithm.

What those highlighting scores they don’t like generally fail to consider, however, is how rare such finds are in a database of over 100,000 foods. I’ve never seen anyone find more than a handful of scores they wanted to protest.

Imagine if you could find 500. Even 500 scores you didn’t like, out of a database of 100,000, would be one-half of 1 percent. That’s a 99.5 percent accuracy rating on your personal scale. How many things in your life would clear that bar?

NuVal isn’t perfect; it can’t be. We don’t have perfect knowledge of nutrition. But we should avoid making perfect the enemy of good. If finding a score you don’t like is a reason to denigrate NuVal, then finding an app you don’t like is a reason to trash your iPhone. Getting advice to turn left where you prefer to turn right is a reason to toss your GPS.

GPS is a good analogy, because it works very reliably — but doesn’t replace your native priorities. In your neighborhood, where you know best, you will outthink your GPS. But the whole point of GPS is to help you get there when you don’t know the way. NuVal is just the same.

New and refined scores are always in the works, just as refinements to the iPhone and iPad are always in the works. But in the interim, NuVal works very well. We know, because it is the first and to date only nutrition guidance system shown to correlate directly with lower rates of chronic disease and premature death. We know, because people using it in the real world have lost over 100 pounds, just by trading up their groceries. Really.

NuVal tells the truth about nutritional quality, as best we can tell it based on the available science, and the consensus of leading experts. As best we can tell it across an expanse of literally hundreds of thousands of foods. It may not be perfect truth, but perfect should not be the enemy of good, or public health will go nowhere. NuVal tells a truth that is good, and reliable, and whole, and effective.

The question now is whether we can handle the common truth, rather than argue over competing priorities. I hope we can, and think we should. We should handle it, taste it, chew it, and swallow. If we can’t handle the truth, then I’m sure that Big Food will be only too happy to keep feeding us their diet of willfully addictive junk, and marketing distortions. Bon appétit.

David L. Katz is the founding director, Yale-Griffin Prevention Research Center.