- Emily Thomas and Simon Tollett
- BBC Food Chain Program
Vitamin D is known to strengthen the health and strength of bones, teeth and muscles, but scientists recently suggested that it has a role in supporting the immune system as well, and it can be used to prevent diseases caused by viruses, such as Covid-19.
What is Vitamin D?
Vitamin D is known as the “sunshine vitamin” because it is the only substance that the body excretes when the skin is exposed to the sun.
Vitamin D helps the body absorb elements such as calcium and phosphorous once it enters the body’s metabolic processes. They are important elements for healthy teeth, muscles and bones.
Studies show that diseases such as rickets, weakness and osteoporosis are a direct result of a significant vitamin D deficiency.
But Professor Kevin Cashman, who specializes in the study of vitamin D, nutrition and bone health at University College Cork in Ireland, says the vitamin is linked to more health problems. He says that those suffering from a deficiency of this vitamin “are more at risk of infection or congestion, which are very important this year.”
He says, “During the past two decades, a new vision for vitamin D has emerged, which has proven its health importance in other areas that are not limited to the skeleton. It helps regulate the immune system.”
Does vitamin D fight viruses like corona?
Professor Cashman says that scientists believe that any vitamin D deficiency, no matter how minor, is associated with “an increased risk of heart and circulatory diseases, diabetes, types of cancer, infectious diseases, and some congestive diseases.”
But is there a direct link between vitamin D and Covid?
Cashman says that preliminary scientific studies “confirm the existence of links between vitamin D deficiency and the effects of Covid-19 on health,” but they are not strong enough to recommend vitamin D “as a method of prevention or treatment” yet.
However, he believes that the research is on the right path, and that the epidemic “has pushed the problems of vitamin D deficiency into the spotlight.”
Scientists agree that the scientific evidence is not yet strong, but experiments are continuing, and “there is new evidence on its way to appear. Covid-19 is one year old, and the data needs some time.” This is surprising if it is proven that vitamin D deficiency is linked to problems with breathing, cold, flu, and more.
“We know that we need vitamin D mainly for bones. If it has been shown to have a positive, or even preventive, effect against respiratory diseases, then it is an added benefit.”
Where do we get vitamin D?
The primary source of vitamin D is mostly sunlight, Cashman said, but the amount we get depends on its concentration in the skin, which changes according to our location on the planet and the time of year.
A general rule of thumb is that the closer we get to the equator, the stronger the sun’s rays and the more vitamin D we get. But some regions, such as India and many African countries, are among the most vulnerable to vitamin D deficiency. How is that?
Cashman says that there are many factors, such as pollution that blocks the sun’s rays or urban life, “along with many cultural reasons, such as clothing related to religion or people fleeing the heat of the sun in the middle of the day.”
But there is another reason that has to do with skin color. Data published by the European Journal of Medical Nutrition indicate that 12 percent of European citizens suffer from vitamin D deficiency, “but this number increases to double and sometimes triple among ethnic groups living in European countries”, because melanin present in dark skin forms A natural sunscreen.
How do we get vitamin D in our food?
Fortunately, food provides an alternative source of vitamin D, as it is found in oily fish, red meat, egg yolks, and dairy products. But for most people, it is difficult to get enough of this vitamin through diet alone.
Most of the foods rich in vitamin D are derived from animal sources, while this element is absent from plants, “which means that a vegetarian diet or the inability to purchase specific foods increases the risk of vitamin D deficiency,” Cashman said.
This is the case in a town like Mongolia, where a study by the BBC’s “food chain” program revealed that about 70-80 percent of adults and 90 percent of children suffer from vitamin D deficiency.
“Food rich in vitamin D is expensive for those who live in poor communities,” said Amara Por, chief operating officer at the Christina Noble Foundation for Children in Mongolia.
She added that the government announced plans to add the vitamin to wheat flour, which is one of the most consumed products in the country, and an easy way to ensure that the vitamin reaches everyone.
Could you be getting too much vitamin D?
Most health organizations recommend a daily dose of vitamin D of at least 10 micrograms, but more than 100 micrograms can be harmful. Large doses over long periods of time can lead to the accumulation of excess calcium in the body, which leads to weak bones and kidney and heart problems.
Cashman says that “vitamin consumption can increase unintentionally, by buying nutritional supplements high in vitamin D or consuming more than one pill.”
He added, “But it is difficult to increase the consumption of the solution required by foods rich in vitamins, because they are added in a more moderate form.”
What other ways to get vitamin D?
One way is to take pills or supplements rich in vitamin D, but it can be costly to millions around the world.
So, an alternative way is to add more vitamin D to our diet, by adding it to “the staple foods that are widely consumed,” Cashman says.
This process is known as food immunization, and it is a method that has been used in industrialized countries for 80 years, and is now being used more in developing countries. And for many nutritionists, this is the best way to beat Vitamin D deficiency around the world.
The types of food that nutrients can be added to vary according to the geographical location, but they include milk and its vegetable alternatives (such as soy, oats, almonds, and rice), juices, yogurt, cream, margarine, wheat flour, cooking oils, breakfast chips and even eggs.
Governments can dictate the addition of these elements or make them a choice for food processors depending on the levels of vitamin D deficiency in the country. Currently, few countries impose vitamin D immunization programs, such as Canada and Finland, which do not have sunlight most days of the year.
“The idea is to find food sources that reach most people so that they get what they need,” says Professor Christel Lamberg-Allardit, Professor of Food and Nutrition at the University of Helsinki in Finland, as she talks about her experience working with the government on vitamin D fortification policies.
Cashman says that the Corona pandemic will encourage other countries to consider strategies such as that of Finland, and he believes that investing in these immunization programs makes sense for several reasons.
One of these reasons is that the vaccination process is inexpensive. Adding vitamin D to a ton of wheat flour costs “several pennies”, in addition to the long-term benefits stemming from improved population health.
A study conducted by the health authorities in Germany in 2015 estimated that fortifying bread reduces fractures among women over the age of 65 by more than ten percent, which means saving $ 380 million annually in treatment expenses.
“Such cost savings are amazing,” says Cashman.