Still news of the study made its to the United States, where vitamin D deficiency is still less common, and NPR said “A Bit More Vitamin D Might Help Prevent Colds And Flu.” Time went further, with “Here's How to Avoid Catching Colds and the Flu.”

The evidence on vitamin D supplements is deeply mixed, of course. At least eight other meta-analyses in the last five years have analyzed the effects of vitamin D supplements on respiratory infections, and only three found benefits. This study was a step toward understanding if fortifying foods would benefit more people than it would potentially harm, but it does not suggest that all people should begin supplementing themselves. So the nut of it—because all of this is understandably tough to make practical, but inevitably will be put into practice one way or another—is that Vitamin D works differently in everyone depending on their levels of vitamin K, phosphate, magnesium, and other elements of diet, as well as exposure to sunlight, clothing choices, and the amount of melanin in a person’s skin (blobs of pigment that block sunlight from creating vitamin D in the body).

There is no consensus on how much vitamin D should to be consumed by “the average person” for optimal health, and I doubt there ever will be—so long as people’s diets and lifestyles vary as much as they do. If we have reached a point as a global population where we need to consider recommendations wherein all people are supposed to be taking a pre-hormone every day for the rest of their lives, there is more to interrogate about how and why that could really be necessary and sufficient.

Most of our vitamin D comes from sunlight, and that creates a huge variable for any attempt at dietary recommendations. No one who works outdoors in the tropics is likely ever going to need a vitamin D supplement. Probably almost everyone who lives in Alaska in the winter (and doesn’t constantly eat fish or drink antique cans of Sunshine Schlitz) would benefit. At the latitudes in between, the amount of melanin in a person’s skin matters a lot. For people living in the U.S., the FDA’s approach seems well worded: “If you are an older adult, have dark skin, or are exposed to insufficient ultraviolet band radiation (such as sunlight), consume extra vitamin D from vitamin D-fortified foods and/or supplements.”

The lead author of the BMJ study, Adrian Martineau at Queen Mary University of London, is an advocate of fortifying foods with vitamin D, as opposed to testing individuals and “topping up those with lowest levels.” In the meantime, he recommends that people in the U.K. take a supplement during the darker winter months. Even though people in the United States are less likely to have a clinically-defined “deficiency,” the new study might be useful to consider for people who get a lot of respiratory infections—or for whom those infections are particularly dangerous—and considered on a person-to-person basis with a physician.

So people are elaborate ecosystems that aren’t begging for blanket recommendations. But if sales of Vitaminwater are any indication, vitamin beer today could sell extremely well. Though the only clear benefit would be to the person selling it.