“Before you jump on a nutrition bandwagon, and start taking supplements or radically change your diet, dig deeper. Be wary. Find reliable sources. Read the actual study.”
As a dietitian working in the wellness field, nutrition-related news always catches my eye. So I was intrigued when I saw several headlines last summer pertaining to vitamin B3. The first group of headlines were about miscarriage: “Vitamin B3 may prevent miscarriage and birth defects, study suggests” and “Landmark Vitamin Discovery Could Prevent Miscarriages and Birth Defects” Then a second group of headlines appeared, this time for vitamin B3 links to skin cancer prevention: “Vitamin therapy could prevent melanoma” and “New review shows potential of Vitamin B3 in preventing melanoma”. Reading the media-written articles about the research, things sounded pretty promising!
However, if there’s one thing I’ve learned as a dietitian, it’s to be skeptical of “too good to true” headlines. So I decided to take some time and investigate the actual basis of the headlines. What I found was surprising, and not in a good way, especially if you went out and bought a bunch of vitamin B3 supplements based on the headlines.
For some background info to start, vitamin B3 comes in two forms: niacin and niacinamide. Niacinamide is derived from niacin, but the two forms are nearly interchangeable in low doses, like the doses found in vitamin supplements. In bigger doses, niacin and niacinamide do vary in their ability to treat certain conditions such as high cholesterol. Vitamin B3 plays an important role in our body’s metabolism, helping convert food into usable energy. Good sources of the vitamin in our diet include meat, fish, nuts, mushrooms, and fortified cereal.
Now, let’s take a look at the study related to miscarriage. An estimated 10-25% of known pregnancies end in miscarriage, so there could be huge implications for millions of people if the headlines are true and vitamin B3 can prevent miscarriage. Researchers were looking specifically at a group of birth defects known as VACTERL association, which causes abnormalities in many different body systems including the spine, heart, kidneys, and limbs. VACTERL association is rare, affecting 1 in 10,000 to 40,000 babies. Researchers studied four families who had been affected by this particular type of birth defect and found that this association was related to a deficiency of a certain compound in the body known as NAD, or niacinamide adenine dinucleotide. NAD is a coenzyme formed from niacin, which allows cells to produce energy, and which is important for normal organ development.
The discovery that NAD was involved and responsible for this group of birth defects alone was a big deal, but then scientists went further and found that when mice with the genetic mutation that will result in VACTERL were given extra niacin, their mouse babies didn’t end up with the expected defects.
It was a well designed study and an important one for the prevention of this specific type of birth defect. But, notice that the study was conducted on only four families and mice, and no niacin was actually given to humans! Furthermore, the dose given to mice was the equivalent of ten times the recommended daily amount for people. We also know that body mass index and diabetes can affect how someone produces NAD, and developing fetuses are particularly sensitive little beings. So, while it’s true that niacin may potentially prevent a certain type of birth defects (if humans react in the same way as mice), we are still a long ways off from recommending extra niacin to all pregnant women or being able to say that niacin will prevent miscarriage and birth defects. In other words, it’s an exciting study, but certainly shouldn’t be interpreted as having widespread ramifications for our entire population yet.
Next, let’s take a look at the study, or review rather, that spawned the headlines related to melanoma. A clinical trial known as ONTRAC was recently conducted which looked at the effect of niacin supplementation on the recurrence of skin cancer. Researchers found a 23% reduction in basal cell and squamous cell skin cancers (both non-melanoma cancers) when people with a history of skin cancer were given 500 mg of niacinamide twice per day as compared to a randomized control group receiving a placebo. It’s a compelling finding for people with a history of non-melanoma skin cancer, especially since niacinamide is safe, inexpensive, and easily available.
However, researchers then hypothesized that vitamin B3 might also be effective in helping to prevent melanoma, based on the promising ONTRAC trial results, as well as the assumed role of vitamin B3 in relation to skin cancer. Vitamin B3 is thought to reduce inflammation and suppression of the immune system caused by UV radiation, and is involved in DNA repair.
So, scientists never actually studied Vitamin B3 in relation to melanoma. They just called for future studies. And yet, somehow, their untested hypothesis that niacin might be able to prevent melanoma got translated into headlines that at first glance anyway, certainly give the impression that there is more of a connection.
Bottom line? Before you jump on a nutrition bandwagon, and start taking supplements or radically change your diet, dig deeper. Be wary. Find reliable sources. Read the actual study. You don’t have to have an advanced degree to find serious limitations of studies including small sample size, animals only, or no control groups. Or, in the case of the melanoma headlines, no study at all; simply a call for future research!
Hopefully we will see follow-up research that support these findings and hypotheses, but in the meantime, the best approach is to get your niacin from a whole-foods based, healthy diet!
Want to learn more about dietary supplementation? Check out our 2016 Webinar Smart About Supplements