Vitamin D can prevent autoimmune diseases, study claims
Taking vitamin D and omega-3 fish oil supplements daily may reduce your risk of developing arthritis, research suggests.
Scientists found that middle-aged adults who took daily doses of the “sunshine vitamin” were 22 percent less likely to be affected by an autoimmune disease.
This umbrella term includes conditions such as rheumatoid arthritis and psoriasis, which are caused by the body’s own immune system attacking its own tissue.
The researchers said more studies were needed to find out why the supplements have the protective effect.
Millions of people in the UK and US have an autoimmune disease and there is no way to reduce the risk of developing it.
But researchers from Brigham and Women’s Hospital in Boston say their new findings suggest this is one way to reduce their risk.
Experts conducted a five-year trial involving nearly 26,000 people over the age of 50. The results were published in the British medical journal.
A long-term study of nearly 26,000 Americans over the age of 50 found that taking a vitamin D supplement reduced the rate of autoimmune disease by 22 percent compared to a placebo group. Most people get the vitamin D they need from sunlight, but in the winter they can get it from oily fish and egg yolks or pills
What is vitamin D and how do I get it?
Vitamin D is a type of vitamin that the human body both obtains from food and produces when exposed to sunlight.
What does it do?
It helps regulate the amount of calcium and phosphate in the body.
These nutrients are needed to keep bones, teeth and muscles healthy.
People who do not get enough vitamin D can develop bone disorders such as rickets in children and osteomalacia (a softening of the bones) in adults.
How do I get enough vitamin D?
In the UK, most people get the vitamin D they need from sunlight between April and September, as long as they go outside.
The body naturally produces vitamin D when it is exposed to sunlight.
Vitamin D is also found in foods such as oily fish, liver and egg yolks.
Should I take a supplement?
The NHS says people should consider taking a vitamin D supplement in the winter month, when sunlight is weaker.
Other people may need vitamin D all year round because they are housebound, or if they have dark skin, which reduces the amount of sunlight their skin absorbs.
Children ages one to four should also receive a 10-microgram (µg) vitamin D supplement daily throughout the year.
How much should I take?
The NHS advises that 10g per day is sufficient for most people.
What happens if I take too much?
Taking too much for a long time can lead to a dangerous build-up of calcium in the body, which can weaken the bones and also damage the heart and kidneys.
The NHS advises adults against taking more than 100 µg per day.
Children from one to ten years old should not consume more than 50 g per day and infants under 12 months should not consume more than 25 mg per day.
Vitamin D is often sold in units called IU. One microgram of vitamin D is equal to 40 IU.
Volunteers were randomly assigned to four different groups, allowing scientists to test the effects of daily vitamin D supplements and omega-3 fatty acids.
One group received a daily dose of 2,000 IU (international units) of vitamin D. They were compared with volunteers who received a placebo.
Anther was given a 1000 mg omega-3 supplement and a placebo daily. They were also compared with a placebo group.
The NHS recommends adults get at least 40 IU of vitamin D a day, but are warned not to take more than 4,000 IU a day as it can be harmful.
After five years, reported cases of autoimmune disease were confirmed using medical records. Those with insufficient documentation for certainty were classified as probable cases.
Of the patients who received vitamin D, only 123 developed an autoimmune disease, compared with 155 in the placebo group.
The scientists calculated this a reduction of 22 percent.
Meanwhile, there were 130 confirmed cases of a diagnosed autoimmune disease in the omega-3 group, compared with 148 in the placebo group — calculated on the equivalent of a 15 percent reduction.
However, the team claimed that this finding was not statistically significant.
But when probable cases were included, the percentage for omega-3 rose to 18 percent, compared to the placebo. This gap was defined as significant.
There was also evidence of increased protection the longer the omega-3 supplement was taken.
The study’s author, Dr. Jill Hahn, said that while autoimmune diseases are common in older adults, before that, medics had no way of reducing people’s risk.
“Autoimmune diseases are common in older adults and negatively impact health and life expectancy,” she said.
“Until now we haven’t had a proven way to prevent them, and now we do for the first time.”
She added that she was excited to see if vitamin D had a similar preventive effect in younger people.
dr. Karen Costenbader, an autoimmune disease expert at Brigham’s, said: “This is the first direct evidence we have that daily supplementation can reduce the incidence of autoimmune diseases, and what appears to be a more pronounced effect after two years of vitamin D supplementation.”
The authors note that their findings may not apply to people who develop autoimmune diseases early in life, and patients should be followed longer to determine how long to protect against supplements.
Autoimmune diseases occur when the immune system cannot distinguish between normal cells and foreign entities.
This causes it to attack healthy tissue, causing a range of problems depending on the nature of the condition.
Psoriasis, rheumatoid arthritis, and lupus are three of the most common autoimmune diseases.
Rheumatoid arthritis affects approximately 400,000 people in the UK and nearly 1.3 million in the US. One in 50 people in the UK are thought to have psoriasis.
Lupus affects the organs, in addition to the skin and joints. In the UK, an estimated 50,000 people have it, with three times as many in the US living with the condition.
While there are treatments available to help alleviate autoimmune diseases, there is currently no cure.
Vitamin D, also called the ‘sunshine vitamin’, is produced by the human body when it is in direct contact with sunlight. It is also found in certain foods such as fatty fish, liver and eggs, and can also be purchased as a supplement.
Many Brits don’t get enough vitamin D in the winter months because of the lack of sunlight and our indoor lifestyle.
Not getting enough vitamin D can cause bones to become soft, weak and develop deformities because of the body’s role in absorbing calcium and phosphate, important nutrients for healthy bones.