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In this 2012 photo, a medical technician fills test tubes with serum and a reagent used to measure the levels of vitamin D in a person’s blood. ( Chicago Tribune)

Medicine

The vitamin D factor

Research shows vitamin D sometimes prevents the common cold. Could it help ward off the new coronavirus?

The research world has mounted an electrifying response to the new coronavirus: Those playing a role include vaccine developers, drug researchers, gene sequencing labs, and the fields of public health and artificial intelligence. In the shadows of this effort is a less glamorous role—that of checking the archives of past research for clues to better treating and preventing COVID-19.

WORLD reader Dr. John Umhau thus calls our attention to a 2017 paper in The BMJ (formerly British Medical Journal). In it, a team performed a meta-analysis—basically, a study of other studies—investigating a common compound and its effect on immunity against respiratory infections like the common cold. The meta-analysis didn’t focus specifically on coronaviruses (a family of viruses that can also cause colds), but it may still apply to them. The drug in question? A humble compound we associate more with milk and bone health: vitamin D.

The meta-analysis combined 25 separate studies and went about it the hard way: Researchers obtained and reanalyzed individual participant data for all 25 studies, tallying up almost 11,000 study participants in what one of The BMJ’s peer reviewers called a Herculean effort. The paper is free to the public, but I’ll summarize it here: The results show that taking a moderate dose of vitamin D daily or weekly (but not more irregular, large doses) helps to protect users from respiratory infections. 

Unsurprisingly, vitamin D supplements were most helpful for study participants who started out deficient in the vitamin, but the supplements may help even those who aren’t. Equally important, people appeared to tolerate the vitamin well: The main problems linked to vitamin D supplementation were high blood calcium levels (in 1 in 200 participants) and kidney stones (in 1 in 500).

Time for a caveat. A figure called the “number needed to treat” (NNT) helps us understand how effective a treatment is. For daily or weekly vitamin D users in the meta-analysis, the overall NNT was 20, indicating a measurable but limited effect. Translating the research lingo into English, this figure means that 1 in 20 people taking vitamin D supplements could expect to avoid a cold because of it. But for study participants with “profound” vitamin D deficiency, the NNT was 4: Every fourth person taking the supplements likely dodged a cold.

So, the big question: Do I, as a doctor, advocate vitamin D supplements based on this research? In moderate doses, yes—especially for those at risk of vitamin D deficiency. (By this point in winter, that’s probably most of us.)

What’s a moderate dose? As the Mayo Clinic notes, “The recommended daily amount of vitamin D is 400 international units (IU) for children up to age 12 months, 600 IU for ages 1 to 70 years, and 800 IU for people over 70 years.” Mayo also offers useful information on potential drug interactions (that’s important to know if you’re on other medications) and cautions that over 4,000 IU per day of vitamin D increases the risk of harmful effects. For those who want to be certain they’re getting enough vitamin D, bloodwork can check whether they’ve hit the recommended level of 50 nanograms per milliliter.

None of this substitutes for the usual advice: Wash your hands frequently, don’t touch your face needlessly, and avoid being around sick people more than necessary. But given how cheap and safe vitamin D is, I’d recommend adding it as well.

In summary, while the research doesn’t yet prove vitamin D is effective against the new coronavirus strain, it does show the vitamin helps protect against common respiratory infections. With the coronavirus and other bugs going around, I plan to start taking vitamin D supplements myself, at least during the winter months.

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Patrick Allard/REA/Redux

(Patrick Allard/REA/Redux)

Medicine

Peanut protection

A new treatment gives hope to children with severe allergies

The doctor fed peanuts to a patient with a serious peanut allergy … 

That may sound like a teaser for a murder mystery or the opening statement in a malpractice lawsuit, but it’s actually a new treatment for food allergies. Oral immunotherapy, or OIT, works the way the ancient King Mithridates VI protected himself from poisons: The patient takes an almost undetectable amount of the harmful substance, then gradually larger doses, until the immune system becomes less sensitive to it. At least, that’s the theory.

Oral immunotherapy moved into the mainstream on Jan. 31, when the U.S. Food and Drug Administration approved Palforzia, the first standardized peanut allergy treatment for children. Palforzia is a peanut flour product designed to provide precise OIT dosings to young patients. Allergists have been preparing similar, customized treatments for individual patients for years.

Mayo Clinic estimates up to 8 percent of children under 3 are allergic to at least one food. The prevalence of food allergies and the lifestyle changes they cause have fueled public interest in potential treatments. Parents of children with food allergies often avoid playdates, camp, and restaurants. At home, cooking a family meal involves thinking about ingredients to avoid. Outside the house, the EpiPen is an ever-present reminder to its owner not to risk trying the food at the party.

The dogma has long been to keep peanut products away from children under 1 year of age, but a 2015 study changed that: The Learning Early About Peanut Allergy (LEAP) study proved infants who regularly eat peanut products are one-fifth as likely to develop a peanut allergy. A follow-up study, Enquiring About Tolerance (EAT), provided similar encouragement for other foods, such as milk, eggs, and fish.

But what of those who already have food allergies? The main advice is still to avoid allergens and carry an EpiPen. The American Academy of Allergy, Asthma, and Immunology cautions on its website that oral immunotherapy’s results are far from the guaranteed safety Mithridates had hoped for: “It is not expected that OIT will lead to ingestion of the allergen without limitation.” 

“Without limitation” is an important caveat, though: Many patients with food allergies, having spent years fastidiously avoiding a particular ingredient, have no desire to sit down with a plate of it. Rather, their hope is to become “bite-proof”—that is, to avoid a serious reaction after a single accidental bite of food—and to tolerate incidental exposures such as a whiff of peanut dust.

Palforzia requires close monitoring by medical staff each time the patient’s dose goes up, which occurs several times over the course of treatment. Most patients do not have a life-threatening reaction to OIT, but it does carry risk. In three months of experimental treatment with Palforzia, almost 1 patient in 10 had a serious allergic reaction. Almost half had less serious reactions.

That’s the downside. The upside: Between one-half and two-thirds of patients in the Palforzia safety studies became able to tolerate 300 milligrams of peanut without serious consequences. In other words, they indeed became “bite-proof.”

Is the benefit worth the risks? The patient must decide that question, balancing the hope of partial immunity against the risk of reactions during treatment—and against the need to eat a small amount of the allergenic food every day, for life, lest the hard-won desensitization fade away. Even though OIT appears to be effective, the American Academy of Allergy, Asthma, and Immunology still offers patients this final piece of advice: Don’t leave the EpiPen at home—just in case.

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Handout

David Adams (second from right) with his 13-year-old son and the quadruplets. Joe McIlhaney and his wife Marion are on the left and right. (Handout)

Medicine

Life trajectory

A pro-life ethic challenged and shaped OB-GYN and fertility doctor Joe McIlhaney’s long career

As a high-school senior, Joe McIlhaney wrote an English class essay on why he wanted to be a veterinarian. When he realized becoming a vet would require four more years of school after college, McIlhaney wondered: “Why do all that to take care of dogs? Why not take care of people?” So he decided to become a doctor.

Now 84, McIlhaney during his 58 years of practice has been an OB-GYN, an in vitro fertilization (IVF) pioneer, and an educator on sexual health. His path was twisting and not without difficulties, but McIlhaney learned the importance of an ethical framework and Biblical foundation.

McIlhaney graduated from Baylor College of Medicine in 1961. After completing a three-year residency in obstetrics and gynecology, McIlhaney moved with his wife and daughters to Austin, Texas.

Soon after Roe v. Wade legalized abortion, a woman visited McIlhaney’s office and said she would kill herself if she couldn’t have one. McIlhaney felt conflicted, but after getting pro-abortion advice from a Christian Medical Society representative and Dallas Theological Seminary’s Bruce Waltke, McIlhaney concluded, “I guess it’s the medical thing to do.” So he performed the abortion. 

Another woman came with a similar story, and McIlhaney performed his second abortion. As he finished the procedure, he saw little legs and feet and what looked like “little, tiny spaghetti”—the baby’s intestines. McIlhaney felt nauseous: “I don’t care what anybody says. These are human beings.” He never aborted another baby.

As an OB-GYN, McIlhaney met many couples struggling with infertility and started the first in vitro fertilization practice in Austin in 1985. As a Christian, he had a few ethical concerns with IVF. He knew the embryos he helped create in the lab were human beings, like the ones he had aborted. So McIlhaney only fertilized as many eggs as a husband and wife were willing to use. 

McIlhaney’s approach to IVF attracted the attention of Eve and David Adams, a Christian couple who had struggled with infertility for nine years. Eve’s appendix had ruptured three months after the couple had their first child, and the scar tissue led to infertility. The couple decided to try IVF when they learned Dr. McIlhaney believed in the sanctity of life.

Eve and David Adams flew from Georgia to Austin, where McIlhaney and his wife, Marion, hosted them. The Adamses decided to have McIlhaney transfer four embryos to raise the chances of pregnancy. They knew the odds of all four implanting and surviving were low.

When Eve went in for her first ultrasound, she told the nurse she had a feeling there were four babies. The nurse brushed her off, until she started counting, “One, two, three, how many did you say?” She told Eve to hold on a minute and ran to get the doctor: Four babies were growing in her womb.

When McIlhaney heard the news, he asked Eve, “Are you mad at me?” She responded, “Are you kidding? No, we’re thrilled!”

On Aug. 31, 1995, Eve gave birth to the first set of quadruplets to be born at Tallahassee Memorial Regional Medical Center. A little more than a year later, McIlhaney and his wife pulled up to the Adamses’ home in Thomasville, Ga., and spotted four little green lawn chairs in the yard. They spent a few days getting to know Olivia, Emily, Stephen, and Stephanie—four healthy children. McIlhaney is thankful he could use IVF to help families like the Adamses: “I’m glad for the babies that I got to be a part of bringing about. It’s God that does it, not me.”

The Adams quadruplets are in their 20s now. Since their birth, a lot has changed in the world of IVF, which troubles McIlhaney: “When you see what’s happened to it, you wonder, was I complicit in that?”

When McIlhaney brought IVF to Austin in 1985, his practice didn’t accept donor sperm or eggs. Now potential parents can shop at an online embryo bank and choose frozen embryos based on the donor’s physical appearance. McIlhaney’s original practice would only freeze as many embryos as a couple agreed to use later in life. In 2017 the Department of Health and Human Services estimated 620,000 embryos were currently cryo-preserved in the United States. McIlhaney compares IVF to a loaded gun: It can protect and it can kill. 

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