Its summer. And just when you thought it was safe to go back in the water our critics are at it again.

In 2011, a few researchers from the University of Minnesota published a study in Archives of Internal Medicine that purported to show that older women who took a multivitamin, or a host of other single ingredient nutrients, were at an increased risk of total mortality. In other words, according to the researchers, supplement usage might decrease, rather than increase, life expectancy. As you might expect, the study generated headlines warning people to stop taking their multivitamin.

At the Council for Responsible Nutrition (CRN), we didnt take those accusations lightly, and we published a peer-reviewed paper that refuted this theory. The article shined a light on the study itself, pointing out flaws, such as the comparisons used to develop the statistics considered participants who were using any combination of other supplements as nonusers" when compared to the multivitamin group.

Last fall, came some good news from the Physicians Health Study II: among the more than 14,000 predominantly white, well-educated and otherwise well-nourished male doctors in the study, those who took a multivitamin had a small, but statistically significant, lower risk of developing cancer.

Now, those who believe in only one way to good health are once again generating headlines that urge people not to take their vitamins. The culprit is a new book (Do You Believe in Magic? The Sense and Nonsense of Alternative Medicine" by Paul A. Offit) that purports to argue mega-dosing of vitamins is unhealthy and FDA is helpless to stop itbut in reality, the publicity campaign goes way beyond that premise.

To begin with, who is advocating mega-dosing of beta carotene or vitamin A? Likely not any mainstream practitioners. The scenarios portrayed in the book are so extreme, they dont reflect the reality of what your average consumer is doing. Moreover, the whole premise from the author illustrates a surprising lack of understanding of the difference between the recommended dietary allowances (RDAs)those levels determined to be the levels we need to maintain sufficiency (to ward off diseases such as scurvy and rickets)and the upper levels (ULs), below which no known adverse effects are seen. For instance, the RDA for vitamin C is 90 mg for an adult man; the UL is 2,000 mg. So if a person decided to use a 500-mg, or even a 1,000-mg, vitamin C supplement, there is still an ocean of safety in between.

For many nutrients, the government-determined RDA may actually be too low (and too outdated) to benefit from science that has demonstrated good news at levels beyond the RDA. Even though the Institute of Medicine (IOM) now says we need" 600 international units (IU) of vitamin D a day, numerous studies have shown benefits for daily intakes of 1,000 IU or more. The IOMs UL for vitamin D is 4,000 IU. 

Its even more alarming the way our critics are also distorting the safety events data about dietary supplements. When FDA received fewer than 2,000 serious adverse reports for supplements in 2012, our critics intimated this was evidence of massive under-reporting of adverse events, rather than acknowledging these numbers could actually demonstrate the relative safety of these products. More recently, data from the U.S. Poison Control Centers were misinterpreted to suggest that every exposure" to a dietary supplement was an actual adverse event.

Finally, there is the question of whether you really need a multivitamin in the first place. A recent Consumer Reports analysis of popular vitamins and other supplements suggested most people dont need to take a dietary supplement if their diet already provides the recommended amount of nutrients.  Thats a pretty big IF. Its sort of like saying we wouldnt need cars if we already had bio-fuel jet packs strapped to our backs.

I still recall an article in the Washington Post from a dietitian who tried to follow the Dietary Guidelines for Americans.  For two weeks, she tried getting all the recommended amounts of all the essential nutrients without completely overdosing on calories by selecting all the perfect fruits and vegetables, grains and lean meats.  Her conclusion is that unless you have a personal shopper and chef, thats a pretty hard goal to reach. So maybe supplements have an important role after all?

The empirical data back this up too. Several recent studies have evaluated the nutrient intake of Americans while examining the eating and supplement habits of the U.S population.  The conclusions repeatedly demonstrated that non-supplement users have significantly higher rates of nutrient insufficiencies. Even among supplement users, RDAs are not always met.  And while there is some hand-wringing of the potential for over-nutrification, the data show the risk of insufficiency is far more prevalent than the risk of consistently exceeding ones ULs. 

So despite the fanfare and headlines, Im going to keep taking my multivitamin for good measure, as well as the other supplements Ive chosen. And Ill keep making sure my family takes theirs too. Im going to keep swimming in the ocean until someone shows me that object on the horizon really is a shark fin, and not just a figment of someones imagination. 

Steve Mister is the president/CEO of the Council for Responsible Nutrition (CRN, crnusa.org), a trade association for the dietary supplement industry.