But it isn't yet clear whether the benefits are only seen in people who are low in vitamin D, and the benefit to people with severe asthma is unclear.
Three people in every 100 who took vitamin D in the studies had to go to hospital with an asthma attack, compared to six in every 100 who took placebo supplements (odds ratio 0.39, 95% CI 0.19 to 0.78).
Asthma is a chronic disease that affects around 300 million people around the world, often giving symptoms of wheezing, coughing, chest tightness and shortness of breath. None of the people taking a supplement suffered any adverse reactions. Evidence suggests it may help prevent respiratory infections, such as the common cold, which can lead to exacerbations in patients.
Review author Professor Adrian Martineau from the Asthma UK Centre for Applied Research, Queen Mary University of London, says in a statement: "This is an exciting result, but some caution is warranted".
The results of a double blind, placebo-controlled study showed that vitamin D made asthma a little easier to live with.
Study researchers mentioned that in the past also there have been studies that have linked low levels of vitamin D in children to increased cases of severe asthma.
An independent review by the Cochrane research body analysed nine recent clinical trials - seven involving 435 children and two studies involving 658 adults, lasting up to a year. The patients were suffering from mild to moderate asthma with a minority having severe asthma. Two trials in more than 2,500 people showed that a year's course of benralizumab injections reduced asthma attacks by a third to a half, according to The Lancet.
Soaking in the sunlight or popping a vitamin D supplement won't worsen your asthma symptoms, but doing either doesn't mean you should leave your emergency inhaler at home.
But vitamin D didn't improve the strength of the lungs or asthma symptoms day-to-day. "We need more trials specifically focusing on children and also specifically focusing on adults with severe asthma to see if those patient groups could benefit", Martineau said. People with low levels of vitamin D seem to be more likely to have asthma attacks. "Further analyses to investigate this question are ongoing, and results should be available in the next few months".
"You can think of vitamin D nearly as a designer drug because it has these two actions, the first being to boost immunity to infections and the second to dampen down inflammation", said Martineau.
Dr. Imran Rafi, chair of clinical innovation and research at the Royal College of General Practitioners, said that to be able to prescribe vitamin D supplements for asthma patients further, research involving both children and adults are necessary.
He said: "More work still needs to be done in gathering the evidence, particularly around effectiveness for young people and children - especially as it now affects as many as one in 11 children".
Tropical Storm Nora brought Yuma its wettest day on record, Meyer said, when nearly four inches of rain fell in one day. The Hurricane Center says Newton's forecast track will take it into southeastern Arizona in the afternoon.
The 17-year-old, who is studying mechanics at Truro College, agreed that she found their confessions reassuring. After the royal couple had left the biomes, en route to the education centre, they ran into someone they knew .
A law enforcement official told The Associated Press that Heinrich took authorities to a field in central Minnesota last week. In 1994, Congress passed a law named after Jacob Wetterling requiring states to establish sex offender registries.
In other news, Auburn defensive back Stephen Roberts will return this week after he served a one-game suspension against Clemson . While getting a win on the road against an SEC team is always a good thing, there is plenty that Clemson has to clean up.
Instead, it says it will use "check and inject" kits - essentially just a dose of epinephrine, a needle, and a syringe. According to NBC New York , the price for two portable shots was $100 in 2008 but this year it's climbed to $600.
He ended up at East Mississippi Community College (aka "Last Chance U") past year , then transferred to Auburn this season. But the Tigers have to play a much more consistent game if they wish to remain behind Alabama in the national rankings.
It has also said it would support any USA initiative to strike Islamic State's stronghold of Raqqa, further to the southeast. They have also clashed with Kurdish-allied forces that Turkey wants to prevent from further expansion in northern Syria.
Under the new deal , PayPal and Venmo uses will also be able to transfer money to their MasterCard debit cards instantly. Apple already offers a mobile wallet and will soon be rolling out an online payment tool, PayPal's bread-and-butter.
Sterling rose to $1.3350, its highest level since August 3 and was on track for the third straight week, its best run since April. This article was published on 2 Sep 2016 (last updated on 2 Sep 2016).
Williams also wowed the crowd when he announced that the hit game Pokemon Go would be coming to the Apple Watch. Williams also announced a special Nike Plus branded Apple Watch, targeted specifically at runners.
The Sioux at Standing Rock have been seeking meaningful dialog and expressing concerns for more than two years with the U.S. The Bakken Pipeline is a 1,134 mile long underground oil pipeline project by the Texas-based company Dakota access.
IOC's Hickey declines questions on ticket scalping in Rio
Share with Us - We'd love to hear eyewitness accounts, the history behind an article, and smart, constructive criticism. Mr Mallon, an executive with THG Sports, was detained in Rio on August 5th along with another employee of the firm.
Robbie Lawler vs. Donald Cerrone set for UFC 205 in NY
The brawl-to-end-all-brawls will take place on the main card of the UFC's inaugural trip to New York City at UFC 205 in November. UFC officials have yet to announce a main event or any other bouts for the promotion's debut event in NY .
Chris Brown And Lawyer Reveal Evidence In Gun Assault
Curran's representatives told ABC News that they don't believe the text is real, and that Curran stands behind her story. He said Los Angeles police made a thorough search of Brown's home, and no guns or drugs were found.
Hull City sign United striker Keane
It felt cruel, on Davies' desire and the spirit Mike Phelan, the temporary manager of Hull, had dragged from his players, but no one from United cared.
UN to meet on N.Korea missile
In 2003, North Korea also tested an anti-ship missile during an Asia-Pacific Economic Cooperation (APEC) summit held in Bangkok. In early August, North Korea fired a missile-also thought to be a Rodong-that landed about 150 miles west of northern Japan.
Deaf driver's shooting death by trooper under investigation
Harris' family said they were not talking to the media Tuesday because they wanted the focus to be on a memorial held at a church. Mecklenburg County District Attorney's Office plans on evaluating the case after law enforcement finishes its investigation.
Hamilton takes Italian Grand Prix pole position
The only problem was that he had his best qualifying in a long time . "It's great to see that we've got so much support". The crowd were unbelievable over the entire weekend and especially during the podium ceremony.
Serena reaches milestone 307th Grand Slam win
In the nightcap in Ashe, 14th-seeded Nick Kyrgios gets his chance on center stage, facing 63rd-ranked Illya Marchenko of Ukraine. Elsewhere, Serena's sister Venus also progressed , along with fourth seed Agnieszka Radwanska and fifth seed Simona Halep.
Germany to fund new school in Italy after quake
In following months Germany took in more than a million migrants, mostly young men from Muslim and Arab countries. Merkel's migration policy "revealed a lack of solidarity in Europe", said Andreas Roedder of Mainz University.