Winter and early spring are associated with vitamin D deficiency and the risk of infections. Vitamin D is produced in our skin after exposure to sunlight. In addition, vitamin D, which is essential for our health, is found in fatty fish (mackerel, tuna, and sardines), mushrooms, and milk or dairy products. To fight infections and maintain health, a person needs vitamin D. Ironically, in winter and early spring, when we need vitamin D the most, many of us do not get enough. It is interesting to know how much vitamin D should we take? Should we take it in the form of food supplements? How to get the necessary amount and most importantly - who needs vitamin D the most? 

In this article, we will discuss the benefits of vitamin D. We will learn what happens to the body when we don't get enough of this vitamin, and we will also learn how to increase our vitamin D levels.

What is vitamin D?

As a result of exposure to sunlight, our body produces vitamin D. However, in early spring, when we are deficient in vitamin D, we can increase our intake of this vitamin through certain foods and supplements. 

Vitamin D is essential for several reasons, including maintaining healthy bones and teeth. What's more, this vitamin may protect us from a number of diseases, including type 1 diabetes.

• Despite its name, vitamin D is not just a vitamin – it is a prohormone, or hormone precursor!

In general, vitamins are nutrients that the body cannot produce, so we must include them in our diet. However, unlike other vitamins, the body can produce vitamin D.

Beneficial functions of vitamin D

This vitamin has many beneficial functions, but above all, vitamin D helps the body:

• Maintaining healthy bones and teeth;

• Helps boost immunity, brain and nervous system function;

• Regulates insulin levels in the blood, which is why it is essential in managing diabetes;

• Supports lung function and cardiovascular health;

• Affects the expression of genes involved in cancer development.

Let's take a closer look at each of these, starting with healthy bones. Various studies have shown that vitamin D plays an important role in regulating calcium and phosphorus levels in the blood. These factors are vital for maintaining healthy bones.

• Vitamin D deficiency in children causes rickets – a condition in which bones soften and the appearance changes dramatically and significantly.

Similarly, in adults, vitamin D deficiency manifests as osteomalacia, or softening of the bones. Osteomalacia leads to decreased bone density and muscle weakness.

Vitamin D deficiency can lead to osteoporosis. According to statistics, more than 53 million people in the United States are either at risk of osteoporosis or are already being treated for it. 

Does vitamin D reduce the risk of flu?

One medical study conducted in 2018 confirmed that vitamin D protects people from the flu virus. However, the authors also reviewed other studies that supported the completely opposite view. 

Therefore, further research is needed to confirm whether vitamin D has a protective effect against the influenza virus. 

Healthy Babies – Vitamin D and Eggs

Vitamin D deficiency leads to high blood pressure in children. A 2018 study showed a possible link between low vitamin D levels and hardening of the artery walls in children. 

In addition, experts from the American Academy of Allergy, Asthma, and Immunology (AAAAI) suggest that a lack of vitamin D increases the risk of allergies. An example of this is children who live near the equator - they almost never end up in the hospital due to allergies. Moreover, these children are not even allergic to peanuts.

AAAAI specialists emphasize in this study that eggs are a source of vitamin D. Infants who started eating eggs after six months were more likely to develop food allergies than those who started eating eggs earlier – at four to six months of age.

Healthy pregnancy

In a 2019 medical study, experts suggested that pregnant women who are deficient in vitamin D may be at risk of developing preeclampsia and premature birth. According to the same study, vitamin D deficiency has also been linked to gestational diabetes and bacterial vaginosis in pregnant women.

Vitamin D deficiency

Although the body can produce vitamin D, deficiency can occur for a variety of reasons, including skin type. For example, dark skin or sunscreen use can reduce the body's ability to absorb ultraviolet (UVB) radiation. However, sunlight exposure is necessary for the body to produce vitamin D. 

• Various sunscreens with SPF factors reduce the body's ability to absorb vitamin D.  

Vitamin D deficiency also depends on geographical location. In particular, people who live in northern latitudes, in areas with high pollution, or who work night shifts should definitely get vitamin D from food.

As for infants who have dark skin and are breastfed, you should definitely add vitamin D to their diet in the form of a food supplement. 

Symptoms of vitamin D deficiency are:

• Regular illness or infections;
• Fatigue;
• Bone and back pain;
• Bad character;
• Impaired wound healing;
• Hair loss;
• Muscle pain.

If vitamin D deficiency persists for a long time, it can lead to complications such as:

• Deterioration of cardiovascular condition;
• Autoimmune problems;
• Neurological diseases;
• Infections;
• Pregnancy complications;
• Some types of cancer – breast, prostate and colon.

The main sources of vitamin D are:

• Fatty fish, such as salmon, mackerel, and tuna;
• Egg yolk;
• Cheese;
• Beef liver;
• Mushroom;
• Yogurt;
• Cereals and juices.