Once a week.
Subscribe to our weekly newsletter.
Multivitamins are not only ineffective, but dangerous
You already get all the vitamins you need on your dinner plate.
For many years, when my doctor would ask what vitamins or supplements I consume on a regular basis, I would reply by saying "a multivitamin." Never once in all those years did she (or he; I've bounced around a bit) ask what type of vitamins were included in the cocktail. No question of percentages, minerals, vitamins—just a head nod and a mouse click.
A few years ago I stopped saying "multivitamin" because I stopped taking one, and he (or she) never asked why, recommended advice, anything. They simply unchecked the box.
For more than half of Americans—68 percent of adults over age 65—a multivitamin (among a few, or many, supplements) is part of the daily ritual. Overloading your body with five or ten times the recommended daily allowance of this or that vitamin is treated as folk wisdom. It's such basic science that questioning it seems like a complete waste of a thought.
Problem is, the National Institute of Health spent $2.4 billion studying vitamins and supplements only to find out they really don't work. As Pieter A. Cohen writes in JAMA:
During the past 2 decades, a steady stream of high-quality studies evaluating dietary supplements has yielded predominantly disappointing results about potential health benefits, whereas evidence of harm has continued to accumulate.
This includes clinical trials showing that vitamin E, once promoted as heart healthy, actually increases your risk of heart failure and prostate cancer. Multivitamins do not prevent cancer and heart disease; St John's wort will do nothing for your depression; Echinacea is no match for the common cold. In smokers, beta-carotene increases the risk of lung cancer.
Photo: patel.dharmesh.vb / Shutterstock
A large part of the problem is how comfortable we are swallowing pills with no understanding of what they contain. Whenever we feel slightly off we immediately imagine the pill that will alleviate the distress. Pain, however, is a sign that something is wrong. Ignoring the signal doesn't solve the problem, it only prolongs the agony.
Since multivitamins have predominantly been marketed as healthy or, at the furthest end of the spectrum, benign, we've overlooked the fact that many are, in the long run, damaging. No vitamin or mineral is without effect. Because we don't exactly understand how these pills operate should not mean we want to pop as many of them as possible.
Cohen points out that while vitamin and supplement bottles must include the standard “not evaluated by the FDA" jargon, most eyes pass right over the small print, instead focusing on unproven health claims scripted in bold, bright letters.
This has caused a number of researchers to remind us that we get all the vitamins we need on our plates. Even those eating a “Western" diet— which is the culprit of America's obesity epidemic—achieve the basic requirements our bodies require. There is simply no proven track record showing that the isolation of certain vitamins from the foods that contain them is beneficial.
This is not to say some people don't require certain vitamins or minerals for a variety of issues. That's a different case from overloading your body with a flood of them hoping something works.
As Marjorie McCullough, strategic director of nutritional epidemiology for the American Cancer Society, is paraphrased in the NY Times:
It's possible that the chemicals in the fruits and vegetables on your plate work together in ways that scientists don't fully understand—and which can't be replicated in a tablet.
Physician Paul Offit agrees. In study after study Offit shows that cancer and heart disease rates increase with the consumption of vitamins and supplements. A few examples:
- A 1996 study in Seattle of 18,000 people showed that people exposed to asbestos who were taking megavitamins with large doses of vitamin A and beta-carotene were 28 percent more at risk of developing lung cancer and 17 percent more at risk for developing heart disease.
- A 2004 study in Copenhagen conducted 14 randomized trials with 170,000 people and discovered that those taking large amounts of vitamins A, C, E, and beta-carotene were more likely to develop intestinal cancer.
- A 2005 study at John Hopkins School of Medicine performed a meta-analysis of 19 studies with over 136,000 people. Those taking megavitamins were at an increased risk of early death.
- Another 2005 study of 9,000 people published in JAMA found increased risks of cancer and heart disease in those taking large doses of vitamin E.
- A 2011 study at the Cleveland Clinic involving 36,000 men found a 17 percent increased risk of prostate cancer in those consuming vitamin E and/or selenium.
Regarding the antioxidant craze—and certain levels of them are healthy—Offit notes that oxidation is required to “kill new cancer cells and clear clogged arteries." Overloading on antioxidants reduces your body's ability to do this.
Fruits and vegetables contain many other ingredients that appear to, as McCullough mentions above, boost the efficacy of vitamins. Offit continues:
Half of an apple has the antioxidant activity of 1,500 milligrams of vitamin C, even though it contains only 5.7 milligrams of the vitamin. That's because the phytochemicals that surround vitamin C in apples enhance its effect.
American regulatory bodies have been too lax in their policing of vitamin and supplement manufacturers. Many are either blatantly lying or ignorant of the science behind the products they're selling. The dietary supplement industry raked in over $32 billion in 2012, most of which profited from junk science, or at best, unproven claims. That's great business for those companies. Unfortunately, it's terrible for us.
Some mysteries take generations to unfold.
- In 1959, a group of nine Russian hikers was killed in an overnight incident in the Ural Mountains.
- Conspiracies about their deaths have flourished ever since, including alien invasion, an irate Yeti, and angry tribesmen.
- Researchers have finally confirmed that their deaths were due to a slab avalanche caused by intense winds.
In February 1959, a group of nine hikers crossed through Russia's Ural Mountains as part of a skiing expedition. The experienced trekkers, all employed at the Ural Polytechnical Institute, were led by Igor Dyatlov. On the evening of February 1, all nine appear to have fled their tents into the Arctic temperatures, for which they were unprepared. None survived.
Six of the members died of hypothermia; three suffered from physical trauma. Some members were missing body parts—a tongue here, a few eyes there, a pair of eyebrows for good measure. According to reports, no hiker appears to have struggled or panicked. They were likely too quickly overtaken by the hostile environment in Western Russia.
All the members were young, mostly in their early twenties; one member, Semyon Zolotaryov, was 38. Good health didn't matter. Given the uncertain circumstances—what made them flee into the bitter cold?—the incident known as Dyatlov Pass has long been the type of Area 51-conspiracy theory that some people love to speculate about. A vicious animal attack? Infrasound-induced panic? Was the Soviet military involved? Maybe it was the katabatic winds that did them in. Local tribesmen might not have liked the intrusion.
Or perhaps it was aliens. Or a Yeti. Have we talked about Yeti aliens yet?
These theories and more have been floated for decades.
a: Last picture of the Dyatlov group taken before sunset, while making a cut in the slope to install the tent. b: Broken tent covered with snow as it was found during the search 26 days after the event.
Photographs courtesy of the Dyatlov Memorial Foundation.
Finally, a new study, published in the Nature journal Communications Earth & Environment, has put the case to rest: it was a slab avalanche.
This theory isn't exactly new either. Researchers have long been skeptical about the avalanche notion, however, due to the grade of the hill. Slab avalanches don't need a steep slope to get started. Crown or flank fractures can quickly release as little as a few centimeters of earth (or snow) sliding down a hill (or mountain).
As researchers Johan Gaume (Switzerland's WSL Institute for Snow and Avalanche Research SLF) and Alexander Puzrin (Switzerland's Institute for Geotechnical Engineering) write, it was "a combination of irregular topography, a cut made in the slope to install the tent and the subsequent deposition of snow induced by strong katabatic winds contributed after a suitable time to the slab release, which caused severe non-fatal injuries, in agreement with the autopsy results."
Conspiracy theories abound when evidence is lacking. Twenty-six days after the incident, a team showed up to investigate. They didn't find any obvious sounds of an avalanche; the slope angle was below 30 degrees, ruling out (to them) the possibility of a landslide. Plus, the head injuries suffered were not typical of avalanche victims. Inject doubt and crazy theories will flourish.
Configuration of the Dyatlov tent installed on a flat surface after making a cut in the slope below a small shoulder. Snow deposition above the tent is due to wind transport of snow (with deposition flux Q).
Photo courtesy of Communications Earth & Environment.
Add to this Russian leadership's longstanding battle with (or against) the truth. In 2015 the Investigative Committee of the Russian Federation decided to reopen this case. Four years later the agency concluded it was indeed a snow avalanche—an assertion immediately challenged within the Russian Federation. The oppositional agency eventually agreed as well. The problem was neither really provided conclusive scientific evidence.
Gaume and Puzrin went to work. They provided four critical factors that confirmed the avalanche:
- The location of the tent under a shoulder in a locally steeper slope to protect them from the wind
- A buried weak snow layer parallel to the locally steeper terrain, which resulted in an upward-thinning snow slab
- The cut in the snow slab made by the group to install the tent
- Strong katabatic winds that led to progressive snow accumulation due to the local topography (shoulder above the tent) causing a delayed failure
Case closed? It appears so, though don't expect conspiracy theories to abate. Good research takes time—sometimes generations. We're constantly learning about our environment and then applying those lessons to the past. While we can't expect every skeptic to accept the findings, from the looks of this study, a 62-year-old case is now closed.
Stay in touch with Derek on Twitter and Facebook. His most recent book is "Hero's Dose: The Case For Psychedelics in Ritual and Therapy."
A recent study analyzed the skulls of early Homo species to learn more about the evolution of primate brains.
For nearly two centuries, scientists have known that humans descended from the great apes. But it's proven difficult to precisely map out the branches of that evolutionary tree, especially in terms of determining when and where early Homo species first developed brains similar to modern humans.
There are clear differences between ape and human brains. Compared to apes, the Homo sapiens brain is larger, and its frontal lobe is organized such that we can engage in toolmaking, planning, and language. Other Homo species also enjoyed some of these cognitive innovations, from the Neanderthals to Homo floresiensis, the hobbit-like people who once inhabited Indonesia.
One reason it's been difficult to discern the details of this cognitive evolution from apes to Homo species is that brains don't fossilize, so scientists can't directly study early primate brains. But primate skulls offer clues.
Brains of yore
In a new study published in Science, an international team of researchers analyzed impressions left on the skulls of Homo species to better understand the evolution of primate brains. Using computer tomography on fossil skulls, the team generated images of what the brain structures of early Homo species probably looked like, and then compared those structures to the brains of great apes and modern humans.
The results suggest that Homo species first developed humanlike brains approximately 1.7 to 1.5 million years ago in Africa. This cognitive evolution occurred at roughly the same time Homo species' technology and culture were becoming more complex, with these species developing more sophisticated stone tools and animal food resources.
The team hypothesized that "this pattern reflects interdependent processes of brain-culture coevolution, where cultural innovation triggered changes in cortical interconnectivity and ultimately in external frontal lobe topography."
The team also found that these structural changes occurred after Homo species migrated out of Africa for regions like modern-day Georgia and Southeast Asia, which is where the fossils in the study were discovered. In other words, Homo species still had ape-like brains when some groups first left Africa.
While the study sheds new light on the evolution of primate brains, the team said there's still much to learn about the history of early Homo species, particularly in terms of explaining the morphological diversity of Homo fossils discovered in Africa.
"Deciphering evolutionary process in early Homo remains a challenge that will be met only through the recovery of expanded fossil samples from well-controlled chronological contexts," the researchers wrote.
Are "humanized" pigs the future of medical research?
The U.S. Food and Drug Administration requires all new medicines to be tested in animals before use in people. Pigs make better medical research subjects than mice, because they are closer to humans in size, physiology and genetic makeup.
In recent years, our team at Iowa State University has found a way to make pigs an even closer stand-in for humans. We have successfully transferred components of the human immune system into pigs that lack a functional immune system. This breakthrough has the potential to accelerate medical research in many areas, including virus and vaccine research, as well as cancer and stem cell therapeutics.
Existing biomedical models
Severe Combined Immunodeficiency, or SCID, is a genetic condition that causes impaired development of the immune system. People can develop SCID, as dramatized in the 1976 movie “The Boy in the Plastic Bubble." Other animals can develop SCID, too, including mice.
Researchers in the 1980s recognized that SCID mice could be implanted with human immune cells for further study. Such mice are called “humanized" mice and have been optimized over the past 30 years to study many questions relevant to human health.
Mice are the most commonly used animal in biomedical research, but results from mice often do not translate well to human responses, thanks to differences in metabolism, size and divergent cell functions compared with people.
Nonhuman primates are also used for medical research and are certainly closer stand-ins for humans. But using them for this purpose raises numerous ethical considerations. With these concerns in mind, the National Institutes of Health retired most of its chimpanzees from biomedical research in 2013.
Alternative animal models are in demand.
Swine are a viable option for medical research because of their similarities to humans. And with their widespread commercial use, pigs are met with fewer ethical dilemmas than primates. Upwards of 100 million hogs are slaughtered each year for food in the U.S.
In 2012, groups at Iowa State University and Kansas State University, including Jack Dekkers, an expert in animal breeding and genetics, and Raymond Rowland, a specialist in animal diseases, serendipitously discovered a naturally occurring genetic mutation in pigs that caused SCID. We wondered if we could develop these pigs to create a new biomedical model.
Our group has worked for nearly a decade developing and optimizing SCID pigs for applications in biomedical research. In 2018, we achieved a twofold milestone when working with animal physiologist Jason Ross and his lab. Together we developed a more immunocompromised pig than the original SCID pig – and successfully humanized it, by transferring cultured human immune stem cells into the livers of developing piglets.
During early fetal development, immune cells develop within the liver, providing an opportunity to introduce human cells. We inject human immune stem cells into fetal pig livers using ultrasound imaging as a guide. As the pig fetus develops, the injected human immune stem cells begin to differentiate – or change into other kinds of cells – and spread through the pig's body. Once SCID piglets are born, we can detect human immune cells in their blood, liver, spleen and thymus gland. This humanization is what makes them so valuable for testing new medical treatments.
We have found that human ovarian tumors survive and grow in SCID pigs, giving us an opportunity to study ovarian cancer in a new way. Similarly, because human skin survives on SCID pigs, scientists may be able to develop new treatments for skin burns. Other research possibilities are numerous.
The ultraclean SCID pig biocontainment facility in Ames, Iowa. Adeline Boettcher, CC BY-SA
Pigs in a bubble
Since our pigs lack essential components of their immune system, they are extremely susceptible to infection and require special housing to help reduce exposure to pathogens.
SCID pigs are raised in bubble biocontainment facilities. Positive pressure rooms, which maintain a higher air pressure than the surrounding environment to keep pathogens out, are coupled with highly filtered air and water. All personnel are required to wear full personal protective equipment. We typically have anywhere from two to 15 SCID pigs and breeding animals at a given time. (Our breeding animals do not have SCID, but they are genetic carriers of the mutation, so their offspring may have SCID.)
As with any animal research, ethical considerations are always front and center. All our protocols are approved by Iowa State University's Institutional Animal Care and Use Committee and are in accordance with The National Institutes of Health's Guide for the Care and Use of Laboratory Animals.
Every day, twice a day, our pigs are checked by expert caretakers who monitor their health status and provide engagement. We have veterinarians on call. If any pigs fall ill, and drug or antibiotic intervention does not improve their condition, the animals are humanely euthanized.
Our goal is to continue optimizing our humanized SCID pigs so they can be more readily available for stem cell therapy testing, as well as research in other areas, including cancer. We hope the development of the SCID pig model will pave the way for advancements in therapeutic testing, with the long-term goal of improving human patient outcomes.
Adeline Boettcher earned her research-based Ph.D. working on the SCID project in 2019.