TIME Diet/Nutrition

Which Fad Diet Is Best for Weight Loss?

Researchers combed through all the available data on these popular diets and compared them head-to-head on weight loss and how well they lowered risk of heart disease

If you’re going to go on a diet, you might as well pick one that meets the most basic criteria of actually working. But proving a diet can deliver weight loss over the long term requires reliable data—and lots of it. That’s what Dr. Mark Eisenberg, professor of medicine at McGill University, and his colleagues went looking for. They scoured existing research about Atkins, South Beach, Weight Watchers and the Zone diets to find out which was most effective and which had the most scientifically rigorous proof to back up its weight-loss claims, especially over the long term. Their results were published Tuesday in the journal Circulation: Cardiovascular Quality and Outcomes.

Each year, north Americans spend more than $66 billion on these and other diets in an effort to shed pounds and keep them off. But when the scientists culled they data on these diets, they could find only 12 studies that met criteria for being scientifically sound and well designed. “What is incredible to me is that dieting is a multibillion-dollar industry, and if we look at the amount of data out there, it’s miniscule in comparison to the market,” he says. “There are very few well-done studies, and most of them look at the short term. And weight loss is obviously a long term issue.”

To qualify as well-done, studies had to involve enough people to produce statistically significant results, have a control group that wasn’t put on a diet but simply educated about good nutrition and the importance of exercise, and follow individuals for more than a year to see if the results held. “In heart-health studies, they involve thousands, and tens of thousands of people. With [diet] studies we’re talking about hundreds at the most,” says Eisenberg.

The 12 strong studies revealed that none of the four diet plans led to dramatic weight loss, and none was significantly better than the others when it came to keeping weight off for a year or more. All were effective in helping dieters to shed about the same number of pounds in the short term: around 5% of their starting body weight. Weight Watchers was more effective than average care in dropping weight, but head-to-head comparisons showed that at one year, Atkins, Weight Watchers and Zone resulted in similar weight loss on average, and that after two years, some of the lost weight was regained by people who followed Atkins or Weight Watchers.

The diets also did not result in differences in heart-disease risk factors, such as high cholesterol, high blood pressure or blood sugar levels. “We couldn’t find big differences between the different diets,” says Eisenberg.

MORE: 14 Fad Diets You Shouldn’t Try

Some of the studies he and his team reviewed included information on how much the dieters were exercising, but others did not. It’s possible that some people who change their eating habits to lose weight may also start exercising, which can contribute to weight loss—suggesting the diet alone may not be responsible for the dropped pounds.

He says that these results shouldn’t discourage dieters who need to lose weight, and suggests that since the diets produce similar results, people should find the one that’s most suited to the way they live and therefore are more likely to stick with. Weight Watchers, for example, involves a more group-based, behavior-modification approach that may be better for people who work well in groups and need some external motivation, while the other three are more centered around individuals and dependent on their own ability to stay with a program over several months. Atkins and South Beach and Zone all focus on lowering carbohydrates and increasing consumption of healthy fats and proteins.

MORE: Americans’ Diets Are Improving (Sort Of)

Given the enormous amount of money spent on diets—and the rates of obesity and type-2 diabetes in the U.S. and Canada—Eisenberg says what’s really needed is more information that can help people to make better choices about which plan is right for them, and to improve their chances of losing weight, not just for a few months but for the long term.

Read next: How to Get in Shape Using Psychology: 6 New Tricks From Research

TIME ebola

Ebola Patient in New York Is Cured and Released From Hospital

Physician who worked in Guinea urged public to refocus attention on West Africa

Craig Spencer, the physician who became the fourth person diagnosed with Ebola in the U.S., was released Tuesday after being deemed free of the virus.

“Today I am healthy and no longer infectious,” he said at a news conference.

Spencer was treated at Bellevue Hospital in New York City for just under three weeks. It’s not clear exactly what therapies Spencer received, although officials said he received “innovative, state of the art treatments” that were learned from other facilities that have successfully treated Ebola patients in the U.S., including Emory University, the University of Nebraska and the National Institutes of Health. Both Spencer and the medical staff at Bellevue, however, did also mention the importance of the supportive care he got, including hydration and nutrition fluids.

“My early detection, reporting and recovery from Ebola infection speak to the effectiveness of the protocols in place for health staffers returning from West Africa,” he said. “I am a living example of how those protocols work. Early detection is critical for both surviving Ebola and ensuring that it is not transmitted to others.”

With his parents in attendance, and surrounded by the doctors, nurses and lab technicians who contributed to his care, Spencer thanked the staff at Bellevue. New York Mayor Bill de Blasio mentioned that staffers had delivered Spencer’s banjo to him as well to help him pass the time.

Spencer, however, was eager to turn the conversation back to West Africa, where he spent five weeks in Guinea, one of the three hardest-hit nations in the outbreak that has killed some 5,000 people. “I cried as I held children who were not strong enough to survive the virus,” he said. Within weeks of his own diagnosis, he received calls on his personal cell phone from many of the patients he had cured who wanted to wish him well and offer any help he might need.

“Please join me in turning the attention back to West Africa, to ensure that medical workers and volunteers do not face stigma upon returning home,” he added. “Volunteers need our support in order to fight the outbreak at its source.”

Sophie Delaunay, executive director of Medecins Sas Frontiers (Doctors Without Borders)-USA, the group for which Spencer was working when he was infected in Guinea, echoed that message. “We could not be more proud of Craig,” she said at the news conference. “He and others [who volunteer to work in west Africa] are to be respected and honored. They protect us all. As they tirelessly care for the sick and try to stop this outbreak, it is imperative that our focus remains squarely on west Africa, the source of the Ebola epidemic. Stopping it there protects us here.”

Spencer’s fiancée, one of the four people who had direct contact with him before he was placed in isolation, remains in quarantine out of an abundance of caution as she monitors her temperature for any potential signs of Ebola. Her quarantine is expected to be lifted on Nov. 14.

TIME Brain

New Hope for Replacing Nerves Damaged by Parkinson’s Disease

Stem cells may provide a new way of regrowing the motor neurons affected by the movement disorder

Reporting in the journal Cell Stem Cell, scientists say that stem cells turned into motor nerves function nearly identically to fetal motor nerves: the kind now used to treat some patients with Parkinson’s disease. That could mean that the stem cells may become an important source of new nerves to replace the ones damaged in diseases like Parkinson’s.

In Parkinson’s, motor nerves that normally produce dopamine, which is critical for regulating muscle movements and controlling dexterity, are damaged, and dopamine levels drop dramatically. The researchers, led by Malin Parmar, an associate professor of regenerative neurobiology at Lund University, took human embryonic stem cells extracted from excess IVF embryos and treated them to develop into motor neurons. They transplanted these neurons into the brains of rats bred to develop Parkinson’s and found that the lab-made cells brought dopamine levels in these animals back to normal levels in five months. The nerves sent out long extensions to connect with other nerve cells in the brain—such networks are important to ensuring coordinated and regulated muscle movements, and without them, patients experience uncontrollable tremors. The effects were similar to those seen when fetal nerves are transplanted into Parkinson’s patients, a treatment currently used to help alleviate symptoms in some patients.

While the results are exciting, it’s just the first step in bringing stem cell-based treatments to human patients. The study did not delve into how well the new neurons functioned and whether they could reverse symptoms of Parkinson’s in the animals. And even if they do improve those symptoms, scientists still have to show that humans could get the same effects. In an editorial accompany the article, Roger Barker of Addenbrooke’s Hospital and the University of Cambridge warned that the exciting possibilities of stem-cell based therapies shouldn’t push scientists—or patients—to expect too much too soon. Before the cells can be tested in people, he writes, it’s necessary to have “a knowledge of what the final product should look like and the need to get there in a collaborative way without being tempted to take shortcuts, because a premature clinical trial could impact negatively on the whole field of regenerative medicine.”

TIME HIV/AIDS

It May Be Possible To Prevent HIV Even Without a Vaccine

"We're removing the doorway that HIV uses to get into cells"

Natural immunity is the most reliable way to protect yourself from viruses, bacteria and parasites. And the best way to acquire such immunity, in most cases, is to expose your immune system to the bug in question—either by getting infected or getting immunized.

Until now, such protection was only possible with diseases like chicken pox or polio. But now, scientists at Harvard University say that people might soon arm themselves against HIV in a similar way, but through a different method.

Chad Cowan and Derrick Rossi, both in the department of stem cell and regenerative biology at Harvard University, and their colleagues report in the journal Cell Stem Cell that they have successfully edited the genomes of blood cells to make them impervious to HIV. In order survive, HIV needs to insert its genome into that of a healthy cell, and to infect these cells, HIV latches onto a protein on their surface called CCR5. If CCR5 is mutated, however, it’s as if the locks have been changed and HIV no longer has the right key; it can’t attach itself and the cells are protected from infection. So the scientists tried a new gene editing technique called CRISPR that allows them to precisely snip out parts of a cell’s genome, and they spliced out the CCR5 gene. To their surprise, the technique was relatively efficient, transforming about half of the cells they treated with CRISPR into CCR5-free, or HIV-resistant, cells.

“It was stunning to us how efficient CRISPR was in doing the genome editing,” says Cowan.

Scientists have previously used CRISPR to make another change in how HIV infects cells; they snipped out the HIV genes that the virus inserted into healthy cells. That process essentially returned HIV infected cells back to healthy ones.

The latest results, however, suggest that the technique may be useful even before HIV gets inside cells. CRISPR could be useful in treating HIV patients if it can replace patients’ own immune cells with the blockaded versions. The cells Cowan and Rossi used were blood stem cells, which give rise to the body’s entire blood and immune system. In order to work as a potential treatment for HIV, patients would provide a sample of blood stem cells from their bone marrow, which would be treated with CRISPR to remove the CCR5 gene, and these cells would be transplanted back to the patient. Since the bone marrow stem cells populate the entire blood and immune system, the patient would eventually have blood cells that were protected, or “immunized,” against HIV. “We’re removing the doorway that HIV uses to get into cells,” says Cowan.

To test this idea, they are already working with another research group to see if the HIV-impervious cells can treat mice infected with HIV.

Because healthy cells would be barricaded from HIV, the process might also lead to a cure for the disease. While the results are currently being tested to treat animals already infected with HIV, it may also be possible to one day transform a person’s immune cell genomes to be protected against the virus. Some people are already fortunate enough to be protected this way—a small percentage of people of European ancestry have natural immunity against HIV because they have two copies of mutated CCR5. They have been well studied and so far, their CCR5 aberrations don’t seem to be linked to any known health issues. “They are totally normal except for the fact that they are resistant to HIV,” says Cowan. “That’s a heartening thing: to have a group of people who are alive today who have been studied and looked at and seem totally fine.”

That’s why clinicians who research the virus and treat HIV patients are excited by the possibilities of CRISPR-aided strategies. If it’s possible to close the door on HIV, then it may be realistic to start thinking about closing the door on the AIDS epidemic in the near future.

Read next: How Meditation May Help People With HIV

TIME ebola

How Guinea Found the Best Way to Survive Ebola

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A medical staff worker of the 'Doctors without Borders' medical aid organization at a center for victims of the Ebola virus in Guekedou, Guinea on April 1, 2014. Seyllou—AFP/Getty Images

As the world waits for new treatments and a vaccine, doctors in Guinea have found the best way to help patients survive Ebola

With the number of cases topping 13,000 and deaths climbing close to 5,000, the current outbreak of Ebola in West Africa is the virus’s worst yet. But from the tragic illness and mortality emerge some important lessons from the region.

The latest, published in the New England Journal of Medicine, details the cases that first appeared in Guinea’s capital city of Conakry between March and April. Unlike in other parts of the region, where the mortality rate from Ebola averages around 60% to 70%, in Conakry it has remained around 43%.

MORE: Here’s What Scientists Know About Ebola in Sierra Leone

Why? As Dr. Robert Fowler, a clinician in pandemic and epidemic diseases with the World Health Organization (WHO) and physician at the University of Toronto, explains, Guinea’s first Ebola treatment center, established in the capital, took a very aggressive approach to handling patients. Working with the humanitarian aid group Medecins Sans Frontieres (MSF) or Doctors Without Borders, the WHO and the country’s Ministry of Health set up a facility where Ebola patients were immediately hooked up to IV fluids and treated for dehydration—often a complication of infection. They were also monitored regularly for changes in their blood chemicals, including the electrolytes that are a marker for whether the body’s cells are getting enough water and nutrients to function. While routine blood work is standard practice at every hospital in developed nations, such testing wasn’t at Conakry health facilities.

“At the beginning of the outbreak, there was no [Ebola] treatment center,” says Fowler. “It evolved from an old cholera treatment facility and the evolution of care went from having no beds to having IVs, IV fluids, antibiotics and antimalarial [drugs]. We were only able to do hand-held point-of-care testing [of blood samples] but that was quite novel for treatment centers anywhere in the outbreak, even though that’s expected and routine almost everywhere else in the world.”

MORE: This Map Will Show You Every Ebola Outbreak in History

The key to helping Ebola patients survive their infection, Fowler and his colleagues saw, was hydrating them with IV fluids, ensuring that their blood work remained stable and addressing any changes in their metabolites as quickly as possible. In the first month of Ebola cases, 37 patients tested positive for the virus, 28 were treated with IV fluids and 16 died. While the death rate remained high, it was lower than that typically seen in other parts of West Africa.

“Our hypothesis has always been that we wanted to establish a culture of very aggressive supportive care for patients who were coming in dehydrated with electrolyte and metabolic abnormalities and try to correct those very early on, so the complications of very severe depletion don’t compound the effects of Ebola virus infection,” Fowler says.

MORE: Why Cuba Is So Good at Fighting Ebola

Fowler is convinced that the key to improving Ebola survival rates is to think about it differently. Instead of thinking of Ebola as an almost-always fatal disease, see it instead as one that is survivable with the right treatments, he says. If people understood that survival is possible—and at higher rates than previously thought—then more people who might be exposed or infected would seek care sooner rather than later, when it’s too late. “I truly do think we can change the way people think about this illness if we evolve the thinking from needing to have isolation facilities…to saying we need rapidly mobilized treatment facilities that can help care for patients with aggressive supportive care as early as possible,” he says.

Even with the dozens of patients he and his team saw at the treatment facility in Conakry, “we just weren’t keeping up with their fluid needs as much as we needed to,” he says. “Collectively as a team, we were thinking we were failing miserably in terms of our goal of delivering optimal care.”

To succeed takes an enormous amount of resources, labor and personnel. Health workers need to routinely draw and measure patients’ blood to track any slight negative changes in their physical state. Fowler acknowledges the need for drug treatments and an effective vaccine, but for now, as thousands of patients struggle to fight off the virus, “we really, really need more health care workers so we can spend enough time with patients and deliver the kind of supportive care that will improve their outcomes,” he says.

MORE: Nurse Explains Why She Fought Ebola Quarantine

Fowler admits the challenges facing recruitment. For starters, working with Ebola patients requires health care personnel to suit up in personal protective equipment that leaves no skin exposed, making them uncomfortable in the equatorial heat of the region. “We are nowhere near hitting the mark that needs to be hit to improve outcomes,” he says. But as data like his starts to build, best practices and the most effective ways to treat Ebola patients are emerging. And hopefully they will start to make a difference.

TIME Developmental Disorders

ADHD Linked to the Air Pregnant Women Breathe

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Heavy traffic can pollute the air with compounds that can contribute to ADHD Alan Hicks—Getty Images

Everything an expectant mother does can have an impact on her baby’s development—including the air she breathes

Research has long connected what a mom-to-be eats and drinks to the health of her baby, and recent studies have even linked behavioral experiences such as stress, sleep and mood to the growing fetus’s development.

Now, scientists reporting in the journal PLOS ONE have pinpointed one exposure that could contribute to a baby’s higher risk of developing attention deficit hyperactivity disorders (ADHD), which the latest data from the Centers for Disease Control show affects around 11% of children aged four to 17 years.

MORE: Early Exposure to Air Pollution Tied to Higher Risk of Hyperactivity in Children

Frederica Perera, director of the center for environmental health sciences at the Mailman School of Public Health at Columbia University, and her colleagues focused in on how the pollutants in the air that pregnant women breathe can affect their babies’ cognitive development. Perera previously found a correlation between polycyclic aromatic hydrocarbons (PAHs) emitted by burning fossil fuels (such as in car exhaust and some forms of residential heating) to developmental delays by age three, reduced IQ in kindergartners and attentional problems by age six. So the team looked specifically at symptoms associated with concentration and evaluated how these effects connected to PAHs might be contributing to ADHD.

The scientists measured the level of PAHs in both the cord blood retrieved when the mothers gave birth and the mothers’ blood following delivery. They also collected urine samples from the children at age three or five years and analyzed them for PAH levels. The children born to mothers with higher levels of PAH during pregnancy had five-fold increased odds of showing symptoms of ADHD than those who were born to mothers with lower levels. The effect remained strong even after the researchers adjusted for the babies’ exposure to air pollution and smoking after birth.

“This is a new finding, and if the PAHs are identified as a contributor to ADHD, that opens up new avenues for preventing ADHD,” says Perera.

MORE: Study Links Exposure to Pollution with Lower IQ

PAHs, says Perera, circulate in the body for a long time, so even brief exposures could contribute to changes in the body. And each person processes the chemicals differently. Some may be more prone to breaking down the compounds into their potentially toxic elements, while others are less affected by the exposure.

While mothers may not be able to control some exposures, such as those from traffic and heating sources, there are some ways that expectant women can reduce their risk. Pushing local legislators to adopt clean air laws is one way to improve air quality, and on a more personal level, families can make sure that cooking areas have proper ventilation, avoid burning candles and incense and other sources of PAHs, and most importantly, ensure that they aren’t exposed to tobacco smoke. “Air quality is a policy problem, but individuals can be empowered to take steps,” Perera says.

MORE: Mom’s Exposure to Air Pollution Can Increase Kids’ Behavior Problems

Women who are pregnant can also eat more antioxidants from sources like fresh fruits and vegetables, since these can counteract some of the oxidative damage that PAHs wreak on fetal cells.

Perera stresses that limiting exposure to PAHs isn’t the only answer to reducing the increasing rate of ADHD in the country. Genetic and other environmental factors all contribute to the disorder, but identifying as many potential factors as possible could start to reduce the effect that the chemicals have not just on mothers, but on their developing babies as well.

TIME Cancer

Promising New Cancer Treatment Uses Immune Cells

A one-two punch is more effective than using two cancer-fighting drugs that boost the immune system against tumors

Cancer researchers are pumping out study after study trying to figure out how best to use the body’s own immune system to fight cancer tumors.

Reporting in the Journal of the American Medical Association, scientists led by Dr. F. Stephen Hodi at Dana Farber Cancer Institute show for the first time that combining two drugs that target the immune system in different ways could help melanoma patients survive longer.

From 2010 to 2011, 245 patients with advanced skin cancer who had not responded to at least one previous treatment were randomly assigned to get a newly approved drug, ipilimumab, designed to help the immune system better target tumors, either alone or in combination with another drug. Ipilimumab (marketed as Yervoy), was among the first anti-cancer medications that allows immune cells to “see” tumors better; since tumors grow from originally normal cells, the immune system often gives them a pass and doesn’t attack them as foreign. But drugs like ipilimumab, called checkpoint blockade inhibitors, help immune cells to look past cancer’s disguise and target abnormally growing tumors.

MORE: A Shot at Cancer

In the study, those who received the combination of ipilimumab and sargramostim, another drug that gives the immune system a laser-like focus on the proteins found on tumors, survived an average of 17.5 months after the study began, compared to 12.7 months for those who took ipilimumab alone. At the end of a year, nearly 70% of those receiving the combination were alive, while 53% of those in the ipilimumab alone group were.

“We show that the combination improves survival, and at the same time decreases side effects,” says Hodi. The patients receiving the two drugs reported fewer gut and respiratory complications, two of the organ systems most affected by checkpoint inhibitor drugs like ipilimumab.

MORE: Why Cancer Drugs May Work Better While You Sleep

The combination, he says, may be more effective since one drug works to suss out tumor cells, like shining a molecular spotlight on them, while the other builds up the body’s defenses against them, allowing immune cells to better target and eliminate cancers.

The time that both groups of patients enjoyed before their melanoma recurred, however, was similar. But Hodi and his team note that the inflammation caused as a side effect of the drugs could be interpreted as early tumor sites, leading researchers to record the presence of tumors that may not be there.

Teasing apart that issue and determining the safe and optimal doses of the combination will require more studies, says Hodi. The dose of ipilimumab he used, for example, was higher than the one approved by the FDA in 2011, since this study was begun before the agency approved the drug. But the idea that a combination of powerful immune-based drugs could help cancer patients fight their disease and survive longer is encouraging. “This world of [new cancer treatments] is moving fast, and there are a slew of possible combinations that others are studying now,” he says. “It’s where the future of cancer therapy will be.”

TIME medicine

Who’s Better at Baby Talk, Mom or Dad?

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ULTRA.F—Getty Images

The latest research shows that moms and dads use baby talk in different ways, and that boys and girls respond to them differently too

In the latest research on how babies first pick up language, it turns out that gender makes a difference.

Reporting in the journal Pediatrics, Dr. Betty Vohr and her colleagues decided to look at how both moms and dads talk to their young babies. Much research has focused on how mothers engage infants, even before they can speak, but fewer studies have focused on the male side of the equation.

Taking advantage of a small recording device called LENA, which they attached to the babies on a vest for 16 hours, Vohr’s team analyzed all of the verbal interactions a group of 33 babies had (none of the babies were born premature). The recordings occurred just after they were born, while the infants were still in the hospital, and again at 44 weeks and seven months. The last two sessions were recorded on days when both the babies’ parents were home.

MORE: How to Improve a Baby’s Language Skills Before They Start to Talk

From more than 3, 000 hours of recordings, the scientists got a good snapshot of the babies’ verbal environments. And the results were both expected and surprising. When babies made sounds, moms were more likely to respond to them verbally than fathers were — “Oooo, sweetie pie, you’re talking this morning.” Mothers responded 88% to 94% of the time to the babies vocalizations, while dads responded only 27% to 33% of the time.

Perhaps because of the increased responsiveness, or because of other reasons, both boys and girls were also more likely to respond to their mothers’ or female voices than they were to male voices.

Vohr says it’s possible that mothers may use more mother-ese — the higher pitched, sing song-y conversational tone that women, more than men, tend to adopt with infants. Mothers may also pair their vocal interactions with more eye contact with the baby, encouraging them to respond more when they hear their mothers’ voices.

“It seems to me that adults talking to children is absolutely the most cost effective intervention a family could do to improve children’s language,” says Vohr, professor of pediatrics at Alpert Medical School at Brown University.

She also found other intriguing gender-based differences. When she compared mothers of girls to mothers of boys, she found that mothers of girls responded more frequently to their babies’ sounds than mothers of boys did to theirs. The same trend occurred for dads; those who had boys tended to respond more frequently to their infants than those who had girls.

“We’re not certain why that is, but the important thing here is knowing that of critical importance in early language development is the need to encourage both parents,” says Vohr. “The more we learn about it, the more we can inform parents of the power they have in just talking and interacting with their infants to improve the long term outcomes for their child and their school readiness.”

Previous studies have documented that the amount of verbal interaction, or “conversations” babies are exposed to even before they can speak, can predict their later language skills and even academic performance in school.

TIME

This Flu Shot Is Not Like the Others

Some people may get a new flu shot that’s made with dog cells instead of chicken eggs

This year Novartis shipped its first full batch of Flucelvax, a new vaccine that was only approved by the Food and Drug Administration in 2012. The company made a limited amount of the shot last year, but there are more doses to go around this flu season. And for the first time, the doses were made at the company’s newly approved U.S. plant in Holly Springs, North Carolina.

The vaccine is made without growing the influenza virus in chicken eggs, which is the way that flu shots were made for more than four decades. Instead, Flucelvax is grown in kidney cells from dogs. The technology means that the shot can be made in less time than a traditional flu shot—enough virus can be churned out in about 65 hours to 75 hours, compared to the six months or so it takes to grow in chicken eggs. It also means that people who are allergic to eggs now have another option for getting immunized against the flu.

MORE: Pregnant Women and the Flu: Why Influenza Is More Dangerous for Expectant Moms

In studies that the FDA reviewed before approving the vaccine, the shot was 84% effective in preventing flu among adults who were vaccinated compared to those who received a placebo. People getting Flucelvax produced around the same amount of antibodies to the influenza virus as those who were immunized with a chicken egg-based flu vaccine.

Using animal cells instead of chicken eggs, say Novartis officials, allows them to have more control over the purity of the final vaccine. How well influenza grows in the chicken eggs is variable—some eggs or batches of eggs help the virus grow, while others aren’t as conducive to producing large amounts of influenza.

The cell-based technology is also a plus during a flu pandemic, since the platform can produce more doses quickly to control an outbreak as a particular influenza virus spreads among a population. The kidney cells are frozen and can be thawed quickly to begin growing virus. The company has produced doses of pandemic flu vaccine against H5N1 using the cell technology, and it’s keeping them in deep freeze as part of the U.S. government stockpile in the event of a pandemic.

The FDA has approved seven different types of flu shots—in addition to Flucelvax and the standard vaccine made from chicken eggs that protects against three strains of influenza, there is also a shot that protects against four strains of flu; for the needle-phobic, one with a microneedle injects just into the skin and doesn’t penetrate into the muscle, making it less painful; for the elderly who need more protection, there is a high-dose vaccine; for younger children there is a nasal spray; and for those allergic to eggs, there’s a shot made from bits of influenza proteins grown in insect cells. Not every doctor’s office or clinic carries every shot, so if you prefer one over the others, call your health care provider to find out if it will be available.

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