We should never have told people to start taking vitamins, and new research linking one type to cancer shows why

They're colorful, chewable, and more affordable than a doctor's visit. And if you believe some of their claims, supplements can do everything from give you an energy boost to help you lose weight. At the very worst, your daily tablet can't do any harm — right?

Not so fast. A growing body of research — including a study published August 22 in the Journal of Clinical Oncology — suggests that some supplements can carry real health risks. These risks range from vomiting and nausea to an increased risk of cancer and death.

Epidemiologists at two American cancer research institutes and the National Taiwan University found evidence to suggest that long-term, high-dose supplementation with vitamins B6 and B12 — two supplements that allegedly increase energy — was linked with an increased risk of developing lung cancer in men who regularly smoked.

For their research, they looked at data from more than 77,000 men aged 50-76 who had signed up for a long-term observational study designed to look at potential connections between supplements and cancer risk. After observing them for 10 years, the researchers found that the men who took more than 20 mg of B6 or 55 micrograms of B12 every day were three times more likely to develop lung cancer than those who didn't take the supplement.

RELATED: See the symptoms of lung cancer: 

6 PHOTOS
Symptoms of advanced lung cancer
See Gallery
Symptoms of advanced lung cancer

Back pain

Getty

Headaches

Getty

Weight loss

Getty

Fatigue

Getty

Bone pain

Getty

HIDE CAPTION
SHOW CAPTION
of
SEE ALL
BACK TO SLIDE

The study has key limitations. First, the men in it all smoked regularly, were older, and were already predisposed to develop the disease. Still, it was large and done over a long period, which suggests that its findings should be taken seriously. The study is also the first of its kind to look at the link between the two supplements, which had been believed to reduce cancer risk, and lung cancer.

"This is certainly a concern worthy of further evaluation," Theodore Brasky, one of the study authors and a cancer researcher at Ohio State, said in a statement.

Most importantly, the work jibes with other research which increasingly hints that supplements are far from the panacea that they have long been made out to be.

Should we have started taking supplements in the first place?

When supplements were introduced in the 1930s and 1940s, they were presented as a way to address nutrient deficiencies that caused illnesses like rickets and scurvy. They were also seen as a way to avoid expensive and difficult-to-access medical treatment.

In recent years, however, a new generation of supplements that targets primarily middle-class and affluent women has emerged . These formulas ooze with the lifestyle trends of 2017: minimalism ("Everything you need and nothing you don't!"), bright colors, "clean eating," and personalization.

The actress Gwyneth Paltrow's new lineup of $90 monthly vitamin packs — released through her controversial wellness company, Goop — have appealing names like "Why Am I So Effing Tired" and "High School Genes." They claim to deliver health benefits like energy boosts and metabolism jump-starts.

Meet some of the most famous people who've battled cancer: 

16 PHOTOS
Well-known figures who have battled cancer
See Gallery
Well-known figures who have battled cancer

Former U.S. President Jimmy Carter

(REUTERS/Neil Hall)

Television personality Robin Roberts

(REUTERS/Lucas Jackson)

Another basal cell carcinoma. Thanks to frequent checks & amazing doctors, all's well. Looks worse w the dressing o… https://t.co/cFIi0Zhmtr

Actress Shannen Doherty

(REUTERS/Mario Anzuoni)

Chef Sandra Lee

(Photo by Noam Galai/WireImage)

Cyclist Lance Armstrong

(Photo by Tom Pennington/Getty Images)

Actress Rita Wilson attends

(Photo by Tara Ziemba/Getty Images)

Former GMA anchor Joan Lunden

(Photo by Lou Rocco/ABC via Getty Images)

TV host Sharon Osbourne

(REUTERS/Kevork Djansezian)

Journalist Tom Brokaw

(Photo by Dimitrios Kambouris/Getty Images)

Actress Christina Applegate

(Photo by Tibrina Hobson/WireImage)

Comedian Wanda Sykes

(Photo by Tara Ziemba/Getty Images)

TV personality Giuliana Rancic

(Photo by Jeff Schear/Getty Images for Michigan Avenue)

Musician Sheryl Crow

(Photo by Kevin Mazur/Getty Images)

Musician Rod Stewart

(REUTERS/Rick Wilking)

HIDE CAPTION
SHOW CAPTION
of
SEE ALL
BACK TO SLIDE

Goop"What is different about what Goop offers is that the combinations, the protocols put together, were done by doctors in Goop's team," Alejandro Junger, a cardiologist who helped design several of Goop's multivitamin packs, told Business Insider.

But a look at the ingredients in "Why Am I So Effing Tired," which Junger helped design, suggests the formula is not based on rigorous science. The vitamin packets include 12.5 milligrams of vitamin B6 — about 960% of the recommended daily allowance (although on Goop's label it is listed as 625%) — and ingredients like rosemary extract and Chinese yam, whose effects have never been studied in humans and for which no standard daily allowance exists.

According to the Mayo Clinic, vitamin B6 — one of the supplements involved in the latest study — is "likely safe" in the recommended daily intake amount: 1.3 milligrams for people ages 19-50. But taking too much of the supplement has been linked with abnormal heart rhythms, decreased muscle tone, and worsened asthma. High doses of B6 can also cause drops in blood pressure, the Mayo Clinic notes, and can interact with drugs prescribed for anxiety and Alzheimer's, as well as Advil and Motrin.

Mario Anzuoni / Reuters"People using any medications should check the package insert and speak with a qualified healthcare professional, including a pharmacist, about possible interactions," the Mayo Clinic's website says.

Junger declined to comment on specific ingredients in the formula but said that many of them were added to "address the most common nutrient-mineral deficiencies of today: B, C, D, and E vitamins, iodine, magnesium, molybdenum, among others."

Another new supplement product that has materialized in recent months is called Ritual, and it arrives at your doorstep in a white-and-yellow box emblazoned with the words "The future of vitamins is clear."

A month's supply of the glass-like capsules — filled with tiny white beads suspended in oil — costs $30. But the pills don't differ much from a standard, cheap multivitamin — they have similar amounts of magnesium, vitamin K, folate, vitamin B12, iron, boron, vitamin E, and vitamin D.

VitaMe, another new supplement manufacturer, ships personalized daily packets with names like "Good Hair Day" and "Bridal Boost" in a box resembling a tea-bag dispenser each month for $40.

Supplements and disease

Researchers have been studying potential links between supplements and disease for decades. The idea is that if supplements are doing any substantive good, we might see evidence of this in long-term studies. Yet the existing research has not supported that idea. In fact, it's mainly found the opposite.

A large recent review published in the Annals of Internal Medicine looked at 27 trials of vitamins involving more than 400,000 people. The researchers concluded that people who took vitamins did not live longer or have fewer cases of heart disease or cancer than people who did not take them.

Another long-term study published in the Journal of the American Medical Association in May divided nearly 6,000 men into groups and gave them either a placebo or one of four supplements touted for their brain-protecting abilities. The results showed no decreased prevalence of dementia among any of the supplement-taking groups.

Scientists have also turned a particular focus to smokers to see if supplements could help decrease the risk of developing diseases like lung cancer (which smokers are already at an elevated risk of developing).

Again, however, the existing studies suggest certain supplements are not providing benefits and may in fact be linked with harm.

Check out the best and worst dietary supplements: 

14 PHOTOS
Best and worst dietary supplements for you
See Gallery
Best and worst dietary supplements for you

Protein powder: Skip it — eat beans, tofu, nuts, fish, or meat instead.

Marketed as necessary for weight gain and muscle building, protein is one of the best-selling supplements in the US.

Protein is good for you — it helps build muscles — but most Americans get plenty in their diets. In fact, most of us get too much. Meat, fish, beans, tofu, and nuts are rich in protein. Plus, numerous companies have been accused of spiking their protein powders with cheap fillers — another reason to avoid the powdered stuff.

Homeopathic remedies: Skip them — they don't work.

Advocates of homeopathy — which involves diluting an active ingredient until there's no measurable quantity left — claim that the treatments can do everything from relieve colds to calm anxious pets.

But homeopathy has repeatedly been shown to be ineffective. A 2005 study published in the medical journal The Lancet found the approach was roughly as effective as a placebo.

Workout boosters like Jack3d or OxyElite Pro: Skip them — they've been linked to illness and at least one death.

For years, the makers of these supplements, whose active ingredient is dimethylamylamine (DMAA), claimed that they increased speed, strength, and endurance.

But in 2011, after two soldiers who used Jack3d died, the US Department of Defense removed all products containing DMAA from stores on military bases. A 2015 indictment against Dallas company USPlabs, which makes OxyElite Pro, accused the company of falsely claiming that its product was made of natural plant extracts. In reality, it contained synthetic stimulants made in China. The indictment also claimed that the use of OxyElite led to several liver injuries and at least one death.

Zinc: Take it — it's one of the only ingredients shown to shorten colds.

Zinc seems to interfere with the replication of rhinoviruses, the bugs that cause the common cold.

In a 2011 review that looked at studies of people who'd recently gotten sick, researchers compared those who'd started taking zinc with those who just took a placebo. The ones on zinc had shorter colds and less severe symptoms.

Creatine: Skip it — eat meat instead.

We all produce natural, low-level amounts of creatine, a compound that helps our muscles release energy. Studies show that we produce more of it when we  eat meat regularly.

Research suggests that taking creatine supplements could have moderate benefits on specific kinds of short-intensity workouts. It appears to help muscles make more adenosine triphosphate (ATP), a chemical-energy transporter. But unsurprisingly, there's no evidence that it's beneficial for other types of exercise involving endurance or aerobics.

So treat yourself to the occasional steak dinner instead.

Weight-loss pills like "Hydroxycut": Skip them — their claims are dubious.

Weight-loss supplements like Hydroxycut claim that they can help you slim down with a boost of "pro clinical" ingredients. The formula once contained Ephedra, a powerful stimulant linked to 155 deaths that was banned by the US Food and Drug Administration in 2003.

Today's ingredients are simply caffeine and four herbal extracts: Lady's mantle, wild olive, komijn, and wild mint. Several studies shown caffeine can help boost metabolism and encourage moderate, short-term fat burning. But no long-term studies show caffeine helps with sustained weight loss.

Antioxidants: Skip them — an excess of these has been linked to an increased risk of certain cancers, and you can eat berries instead.

Coenzyme Q10, lipoic acid, selenium, flavonoids, polyphenols, and some vitamins (like vitamin E) are antioxidants found in many fruits — especially berries — and veggies. Some have been touted for their alleged cancer-prevention abilities, while others have been sold under the premise that they protect the brain against dementia.

But studies suggest that when taken in excess, antioxidants can actually be harmful. A large, long-term study of male smokers found that those who regularly took Vitamin A were more likely to get lung cancer than those who didn't. In a study published in March 2017, 7,500 men were split into four groups, and given vitamin E, selenium, both, or a placebo for 5 years. The results suggested that the prevalence of dementia didn’t differ significantly amongst any of the groups.

2007 review of trials of several types of antioxidant supplements put it this way: "Treatment with beta carotene, vitamin A, and vitamin E may increase mortality."

Folic acid: Take it if you're pregnant or want to get pregnant.

Our bodies use folic acid to make new cells. The National Institutes of Health recommends that women who are currently pregnant or who want to get pregnant take 400 micrograms of folic acid daily, since their bodies demand more of this nutrient when carrying a growing fetus.

Several large studies have also linked folic acid supplementation before and during pregnancy with decreased rates of neural-tube defects, which are serious and life-threatening defects of a baby's brain, spine, or spinal cord.

Green-coffee extract: Skip it — the only study backing it was pulled.

"You may think magic is make-believe, but this little bean has scientists saying they've found the magic weight-loss cure for every body type," Dr. Oz said of green-coffee extract on his show in 2012.

Unfortunately, there was only one study backing green coffee's alleged weight-loss capabilities, and it was funded by the extract's manufacturer. The study was retracted a few months later.

Green-tea extract: Try it — it's been linked with some health benefits, and is generally considered safe.

A series of preliminary Mayo Clinic studies conducted in 2010 showed promise for the potential use of a chemical component of green tea (epigallocatechin gallate) in reducing the number of cancer cells in patients with chronic lymphocytic leukemia. Research on green tea consumption in people with other forms of cancer has been too limited to say whether it's beneficial.

Brewing and drinking green tea is the easiest way to get the extract, but it's also added to foods like yogurt and other beverages, or available in pill form.

Fish-oil pills: Skip them — you can eat salmon instead.

It's been claimed that the omega-3 fats in fish oil can boost brain function. But the evidence isn't very strong. 

A 2012 review of three large studies found that older people who took omega-3 supplements for anywhere between five months and three years didn't see improved memory or verbal skills.

"Direct evidence on the effect of omega-3 ... on incident dementia is lacking," the authors wrote.

Ginseng: Skip it — scientists say more research is needed to prove that it's safe.

two-month 2010 study of nearly 300 cancer patients at the Mayo Clinic found that those given 1,000 or 2,000 milligrams of ginseng each day reported feeling more energized compared with those who took a placebo. Other research suggests that ginseng can help relieve moderate fatigue in healthy people as well.

But more studies on its long-term safety are needed.


 

Gingko biloba: Skip it — the studies don't prove it helps.

Ginkgo biloba, which comes from the maidenhair tree, is one of the best-selling products in the US for memory loss and is often marketed as a "brain booster."

But the evidence is inconsistent. A small 2006 study found ginkgo was as effective as the drug donepezil for boosting attention and memory in people with mild to moderate Alzheimer's. But a large 2008 study of healthy older people found no evidence that ginkgo helped to prevent dementia, including Alzheimer's. A 2009 follow-up study also found no evidence that gingko slowed cognitive decline or memory loss.

HIDE CAPTION
SHOW CAPTION
of
SEE ALL
BACK TO SLIDE

A large, long-term study of male smokers found that those who regularly took vitamin A were more likely to get lung cancer than those who didn't. And a 2007 review of trials of several types of antioxidant supplements put it this way: "Treatment with beta carotene, vitamin A, and vitamin E may increase mortality."

With all of this in mind, experts say it's wiser to hold off on taking supplements and instead look to food to get the nutrients we need.

"Consumers should expect nothing from [supplements] because we don't have any clear evidence that they're beneficial," S. Bryn Austin, a professor of behavioral sciences at the Harvard T.H. Chan School of Public Health, told Business Insider. "And they should be leery that they could be putting themselves at risk."

NOW WATCH: Here’s how to tell if the solar eclipse ruined your vision

See Also:

SEE ALSO: The $37 billion supplement industry is barely regulated — and it's allowing dangerous products to slip through the cracks

Read Full Story