Vitamin D has been credited for maintenance of healthy bones and teeth and protection against cancer, diabetes and other diseases. But thanks to researchers at University of Colorado, USA, we now know that higher doses of vitamin D – 3300-4300 units daily – can also prevent against acute respiratory infections (ARIs) by cutting down the risk of influenza, bronchitis and pneumonia by 40% in older adults.
The US Center For Disease Control And Prevention (CDC) states that 8.1% of the US population is vitamin D deficient with African Americans and Hispanics at higher risk than the Caucasian population.
To overcome the vitamin deficiency, the National Institute of Health (NIH), USA, recommends a dietary intake of 400 International Units (IU) of vitamin D in children aged 0 to 12 months, 600 IU in people from ages 1 to 70 years and 800 IU in old people aged 70 years and above. The recommendations are equal for both males and females.
Acute respiratory infections interfere with the proper functioning of the respiratory system due to a viral or bacterial infection in the upper respiratory tract, bronchial tubes or in the lungs. The infections include pneumonia, bronchitis, influenza, asthma and a few others and can be dangerous in people with weak immune systems such as old people.
The findings of the trial, led by Adit Ginde, MD, MPH, and professor of emergency medicine at the University of Colorado School of Medicine, aim to help reduce the chances of serious illnesses, especially ARIs and death among older patients aged 80 and above, in long-term care nursing homes and other medical facilities.
The clinical trial is the first to examine the benefit of vitamin D on respiratory infections in old people at nursing homes. 107 patients with an age of 60 years or older were selected for the trial over a 12 month period and were divided into 2 groups.
The first group comprising 55 patients received a dose of 100,000 IU of vitamin D on a monthly basis, about 3,300-4,400 UI daily, while the other group of 52 people received a lower dose of 400-1,000 UI on a daily basis.
The scientists found that those receiving higher doses had a reduced risk of developing ARIs but had an increased chance to suffer falls without injuries.
Ginde says, “This is a potentially life-saving discovery. There is very little in a doctor’s arsenal to battle ARI, especially since most are viral infections where antibiotics don’t work. But vitamin D seems able to potentially prevent these infections.”
The study was published in Journal of the American Geriatrics Society.
Vitamin D, or the sunshine vitamin, is crucial for bone growth and strength. Earlier this year, we found vitamin D to prevent risk and exacerbations of asthma in patients.
According to the study, severe asthma attacks require systemic corticosteroids such as vilanterol. However, vitamin D supplements taken with standard asthma drugs have the potential to reduce asthmatic bouts.
A similar study looks at the effects of vitamin D supplements in reducing the risks of influenza in school children, the results of which proved that vitamin D supplements can reduce influenza symptoms in school children.
Additionally, there is a need to get as much sunlight in autumn, winter and cloudy weather since sunshine is scarce during these times of the year. Therefore, children are at greater risk of developing vitamin D deficiency during colder periods of the year which can lead to a weak immune system resulting in cases of influenza, bronchitis and asthma.
Proper intake of vitamin D has other benefits as well. A study has proved that vitamin D can enhance exercise performance and reduce the risk of cardiovascular diseases by reducing blood pressure and lowering the levels of cortisol in the urine.
In addition, adequate levels of vitamin D in the body assist in the regulation of calcium and phosphate in the blood which is essential.
Different Ways To Get Vitamin D
Almost all of the American milk supply is fortified with 100 IU of vitamin D per cup. The other sources of vitamin D include fish like salmon, mackerel and tuna, beef liver, cheese, yogurt and egg yolks. Some varieties of mushrooms also contain vitamin D.
Some people meet their requirements of vitamin D through exposure to sunlight. When ultraviolet radiation touches skin, it converts 7-dehydrocholesterol to previtamin D3, which in turn becomes vitamin D3. Season, time and length of the day, cloud cover and melanin content in the skin are factors to how much vitamin D is synthesized in the body through sunlight exposure.
According to the American Dietary Guidelines, approximately 5-30 minutes of sun exposure between 10 AM to 3PM at least twice a week without sunscreen could lead to sufficient vitamin D synthesis. In addition, those tanning beds which emit 2% to 6% ultraviolet B radiation are also effective.