Friday Favorites: Elderberry Benefits and Side Effects – Does It Help with Colds and the Flu?

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The CDC recommends everyone over the age of six months get a routine annual flu shot every year––unless you have some sort of contraindication, such as an allergy to any of the components. They recommend trying to get it by the end of October, but it may be beneficial even in December or later.

How effective are flu vaccines? It depends on the year, but typically, it reduces the risk of getting the flu by about 40 to 50 percent. So, in healthy adults, we can say with moderate certainty we can decrease the risk of getting it from like 2 percent each year down to just under 1 percent. Among older adults, you may get a similar relative risk reduction, but the baseline risk is higher, and the consequences greater; so, the absolute benefits are greater, too. In kids, flu vaccines really shine—a high certainty of evidence of a substantial drop in risk. But even in this kind of best-case scenario, with vaccination, there’s still a risk, so what else can we do?

Each year, Americans experience millions of cases of influenza, and hundreds of millions of colds. What about elderberry supplements? In a test tube, elderberry extracts can inhibit pathogens, including the flu virus. In a petri dish, it can rev up the production of flu-fighting molecules from human immune system cells, like tumor necrosis factor, as much as nearly 45-fold. And elderberry juice can help mice fight off the flu. But what about actual people?

The first clinical trial was published back in the 90s: a double-blind, randomized, placebo-controlled trial to treat flu-like symptoms. And the odds for improvement before the fifth day in the treated group were more than 20 times the odds in the control group (p < 0.001). Two subsequent double-blind, randomized, placebo-controlled trials showed similar accelerated healing in the elderberry groups.

This is the study I was excited to see: elderberry supplementation for cold symptoms in air travelers, given my 200-city book tour. It was a randomized, double-blind, placebo-controlled clinical trial of 312 economy-class passengers. And while taking elderberry didn’t seem to prevent people from coming down with cold symptoms, the duration and severity of symptoms in those who did get a cold seemed to have been lessened, suffering an average of about five days instead of seven.

A similar study using the herb echinacea found a lessening of symptom scores that was of only borderline statistical significance. But if you compile all such studies together, even though most of the individual trials didn’t find statistically significant improvements, put them together, and there may be about a 20 percent decreased cold incidence (though there is a concern about selective reporting and publication bias, meaning a bunch of findings and entire studies seem to be MIA, suggesting maybe negative studies were quietly shelved). So, we’re really not sure about echinacea, but all the elderberry studies seemed to have positive results, suggesting elderberry supplementation provides an effective treatment option when more serious treatment isn’t needed. This conclusion came from someone with apparent conflicts of interests, though: each of the four elderberry studies were funded by the elderberry product companies themselves.

Any other berries that might help? A randomized, placebo-controlled interventional study funded, predictably, by Ocean Spray, found that the gamma-delta-T-cells of those drinking a low-calorie cranberry juice beverage for 10 weeks appeared to be proliferating at nearly five-fold the rate. These immune cells serve as like our first line of defense. Though they didn’t get fewer colds, they did seem to suffer less, but not enough to actually prevent days missed from work or an impairment of their activities.

But at least cranberries have never been reported to cause pancreatitis. Some guy taking an elderberry extract not only suffered an attack of acute pancreatitis––a sudden painful inflammation of the pancreas, it went away when he stopped it, and then re-appeared again years later when he tried taking it again, which suggests a cause-and-effect. Why take elderberry extracts, though, when you can just eat the elderberries themselves? Well, cooked are fine, but consuming raw elderberries can cause you to puke your guts out.

Oh, now you tell me! I found out the hard way, as I explained in an answer to the question “What was the worst day of my life?” in my How Not to Die “London Real” interview. It turns out elderberry fruit form cyanide, such that eight people had to be medevacked out after someone brought freshly squeezed elderberry juice to a gathering.

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