Learn about the symptoms, consequences and ways to prevent vitamin D deficiency. Find out how to take care of your vitamin D levels and when to get tested.
Table of contents
- What is vitamin D and why is it so important?
- The most common symptoms of vitamin D deficiency
- What does long-term vitamin D deficiency lead to?
- Vitamin D level testing – when and how to perform it?
- How to prevent vitamin D deficiency?
- Recommendations for supplementation and healthy lifestyle
What is vitamin D and why is it so important?
Vitamin D is a unique fat-soluble compound that plays a key role in the human body not only as a classic vitamin, but also as a hormone. There are two main forms of this substance – vitamin D2 (ergocalciferol) of plant origin and vitamin D3 (cholecalciferol) synthesized in the skin under the influence of solar UVB radiation and supplied from animal products. The main source of vitamin D for humans is skin exposure to the sun, but in our latitudes and with limited time spent outdoors, we are not always able to ensure that we get enough. Vitamin D is being discovered as one of the most important substances responsible for the proper functioning of the body. Its properties go beyond the classic role of supporting calcium-phosphate metabolism and bone mineralization, with which it has long been associated. It is thanks to vitamin D that the body can effectively absorb calcium from the gastrointestinal tract, which is crucial for maintaining strong bones and teeth and preventing rickets in children and osteoporosis in adults. Adequate levels of this vitamin also reduce the risk of fractures, promote the healthy development of the skeletal system during growth, and slow the demineralization of bones in later life.
The need to maintain proper vitamin D concentrations in the body is also due to its very broad effects on other systems and organs. Numerous scientific studies confirm that receptors for vitamin D are found in virtually every cell of the human body, which means that its deficiency can negatively affect many aspects of health. Vitamin D has an immunomodulatory effect, participates in the proper functioning of the
The most common symptoms of vitamin D deficiency
Vitamin D deficiency is one of the most commonly diagnosed nutritional deficiencies in the population, and its effects are often hidden or nonspecific, so they can go unnoticed for a long time. Symptoms of vitamin D deficiency tend to increase gradually, and their intensity and type largely depend on age, lifestyle, chronic medical conditions and individual predispositions of the body. The most common and recognizable symptom is chronic fatigue and a feeling of general weakness. People deficient in this component often complain of reduced physical performance, difficulty concentrating and increased susceptibility to infection, which is associated with a weakened immune system. It is also not uncommon to experience muscle, joint and bone pain – these can be one of the first signs that the body is lacking vitamin D. Bone pain, especially in the lumbar spine, ribs or limbs, as well as stiffness and difficulty moving in the morning, are symptoms to watch out for, especially in people who lead sedentary lifestyles and avoid sun exposure. In children, vitamin D deficiency most often takes the form of rickets, manifesting itself in disorders of bone mineralization, delayed growth, skeletal deformities or muscle pain, while in adults the consequences are sometimes osteomalacia and
Less obvious, but equally significant, symptoms of vitamin D deficiency also include lowered mood, a tendency to depressive states, irritability and decreased sleep quality. The link between vitamin D deficiency and mental disorders is the subject of numerous studies, which confirm that regular deficiency of this vitamin can lead to an increased risk of depression, mood swings or chronic feelings of apathy, which significantly reduces the comfort of daily functioning. It is worth noting that vitamin D deficiency can also affect calcium-phosphate metabolism, resulting in the deterioration of teeth (including brittle teeth, susceptibility to decay) and weakening of hair and nails – they become brittle, grow more slowly and lose their healthy appearance. Dermatological changes, such as skin dryness and susceptibility to skin inflammation, are also not uncommon. With prolonged deficiency, heart disorders (e.g., hypertension, palpitations), headaches, increased sensitivity to stress, and cognitive dysfunction, manifested as problems with memory or concentration, can occur. Particularly alarming are osteoarticular and muscular symptoms in the elderly, in whom vitamin D deficiency is associated with an increased risk of falls and bone fractures. It is important to remember that symptoms of vitamin D deficiency can be confusing and easily attributed to other disease entities or overlooked, which is why it is so important to monitor vitamin D levels regularly and respond to any alarming symptoms, especially if you belong to risk groups such as the elderly, people with darker skin, pregnant women or those who avoid sun exposure.
What does long-term vitamin D deficiency lead to?
Long-term vitamin D deficiency carries serious health consequences that can affect various systems and organs in the body. One of the most important roles of vitamin D is to regulate calcium-phosphate metabolism, which is essential for the proper functioning of bones and teeth. Its deficiency leads to impaired calcium absorption from the gut, causing bone demineralization, which over time results in rickets in children and osteomalacia and osteoporosis in adults. Chronic neglect of supplementation and ignoring sun exposure recommendations causes bones to become brittle, significantly increasing the risk of fractures, skeletal deformities, skeletal muscle weakness and postural problems. The elderly in particular are at risk of reduced bone mineral density, which translates into an increased risk of falls and complications such as slow healing of injuries and prolonged recovery from fractures. In children and adolescents, deficiency can lead to growth retardation, impaired tooth mineralization and susceptibility to tooth decay. Vitamin D also has a significant impact on the immune system – its chronic deficiency is associated with increased susceptibility to viral and bacterial infections, including recurrent colds, flu or respiratory infections. It has also been proven that people with insufficient levels of this vitamin are more likely to suffer from autoimmune diseases, such as multiple sclerosis, rheumatoid arthritis and type 1 diabetes. Thanks to its immunomodulatory properties, adequate levels of vitamin D help maintain a balance between the immune response and inflammation, while a lack of it can contribute to the development of chronic inflammation in the body.
In addition to affecting bones and immunity, long-term vitamin D deficiency affects many other aspects of health. In adults, there is an increased risk of developing cardiovascular diseases such as hypertension, arteriosclerosis and heart failure. There is evidence to suggest that deficiency of this vitamin reduces the elasticity of blood vessel walls, increases atherosclerotic processes and affects adverse changes in the blood lipid profile. Epidemiological studies also indicate the association of vitamin D deficiency with metabolic disorders, such as insulin resistance and an increased risk of developing type 2 diabetes. It should be noted that vitamin D affects the normal functioning of the nervous system, and its deficiency is associated with an increased incidence of depression, depressed mood, anxiety disorders, problems with memory and concentration. In the elderly, its chronic deficiency is sometimes associated with accelerated cognitive loss and the development of neurodegenerative diseases such as Alzheimer’s disease. Insufficient levels of vitamin D also take a toll on the condition of the skin, hair and nails – dermatological problems, delayed wound healing, brittleness and dryness of the hair and increased brittleness of the nails can occur. There are also fertility disorders, an increased risk of pregnancy complications (including pre-eclampsia, gestational diabetes) and difficulty maintaining a pregnancy. People with obesity, chronic gastrointestinal diseases (e.g.,
Vitamin D level testing – when and how to perform it?
Monitoring vitamin D levels in the body plays a key role in the prevention and treatment of vitamin D deficiency. Determination of vitamin D levels is recommended primarily for people in at-risk groups, which include the elderly, pregnant and breastfeeding women, children and adolescents in the period of intensive growth, as well as obese people and those struggling with chronic conditions – especially autoimmune diseases, celiac disease, chronic kidney disease or malabsorption syndrome. Increasingly, the test is also recommended for people with sedentary lifestyles and who do not regularly expose themselves to sunlight, as well as those who follow elimination diets and do not eat fish or vitamin D-rich foods. An obvious indication for testing is the appearance of symptoms suggestive of deficiency, such as chronic fatigue, muscle and bone pain, concentration problems, lowered mood or frequent infections. As a prophylactic measure, especially after the autumn-winter season, it is advisable to determine the level of this vitamin, since this is when skin production is lowest and deficiency is easiest. Regular vitamin D testing takes on exceptional importance in supplementation users, as it helps determine whether the doses taken are effective and safe, and prevents the risk of overdose resulting from over-supplementation.
The vitamin D level test is performed from a venous blood sample, regardless of the time of day, and the patient does not need to be fasting – however, some laboratories still recommend limiting meals and avoiding supplements on the day of the test to get the most reliable result. Most commonly, the concentration of total 25-hydroxyvitamin D [25(OH)D] – considered the most accurate indicator of the body’s vitamin D supply – is determined. The optimal range of 25(OH)D levels for most of the population is 30-50 ng/ml (75-125 nmol/l), with results below 20 ng/ml (50 nmol/l) indicating deficiency. This test is commercially available at almost every analytical laboratory, and is increasingly being reimbursed for certain groups of patients. The result is usually obtained within a few days and should be interpreted in the context of the patient’s individual characteristics, age, health status and current recommendations of scientific societies. If a deficiency is found, the next step is to consult a doctor, who will select the appropriate therapy. However, it should be remembered that abnormal vitamin D levels can result from both inadequate supply of vitamin D with food, insufficient sun exposure, absorption disorders and metabolic problems, so interpretation should be comprehensive. Systematic monitoring of vitamin D levels makes it possible not only to detect deficits or excesses of this vitamin early, but also to individualize the dosage of supplements and evaluate the effectiveness of preventive and therapeutic measures taken. It is worth realizing that despite the popularity of vitamin D supplementation, only a rational approach supported by reliable laboratory diagnostics can bring measurable health effects and ensure the safety of the therapy used.
How to prevent vitamin D deficiency?
Preventing vitamin D deficiency requires a multidirectional approach that takes into account both the natural mechanisms of synthesis of this vitamin in the body, as well as factors related to diet, lifestyle and individual predisposition. The most important, and also the most natural way, is to benefit from exposure to sunlight – it is under the influence of UVB radiation in the skin that vitamin D3 is synthesized. Experts recommend daily, moderate contact with the sun, preferably between 10 am and 3 pm, exposing at least 18% of the body surface (arms and legs), which for 15-20 minutes a day allows to produce enough vitamin D. However, be sure to use common sense to avoid sunburn and excessive risk of skin cancer. In Poland, due to its geographic location and the low number of days of sunshine during the autumn-winter period, the synthesized amount of vitamin D often turns out to be insufficient, so during this time special attention must be paid to other sources and supplementation prophylaxis.
The second pillar of preventing vitamin D deficiency is a well-balanced diet that includes foods rich in this compound. In the daily menu, it is worth including fatty marine fish, such as salmon, mackerel, herring and sardines, which are one of the best natural sources of vitamin D. Also, cod liver oil, egg yolks, milk and milk products, ripened cheeses and fortified products (such as margarines, plant milk or breakfast cereals) can help increase the level of this vitamin in the body. Unfortunately, even a very well-balanced diet rarely covers the total requirement for vitamin D, especially in the elderly, vegetarians, vegans or people with malabsorption disorders. In such cases, vitamin D supplementation in the form of dietary supplements becomes essential. The Polish Food and Nutrition Institute and the Chief Sanitary Inspectorate recommend prophylactic supplementation between October and April for most of the population, and year-round for those who rarely spend time in the sun or cover their bodies with clothing. The choice of supplementation dosage should be guided by individual needs, laboratory test results and physician’s indications; a typical preventive dose for adults is 800 to 2,000 IU per day, while in children, the elderly, pregnant women or obese people, doses may be higher and should be determined by a specialist. It is worth remembering that excessive supplementation is associated with the risk of
Attention to overall lifestyle and avoidance of factors that may impede proper vitamin D synthesis or absorption is also an important part of prevention. Particular attention is paid to people with dark complexions who use creams with high UV filters, elderly people with reduced renal function, patients with chronic gastrointestinal diseases (such as celiac disease or Crohn’s disease), as well as obese individuals, in whom vitamin D may be stored in adipose tissue and thus less available to the body. In these groups, regular diagnosis and ongoing cooperation with a physician are particularly important. For those with limited sun exposure, it is also advisable to take care of physical activity outdoors, use balconies or gardens even on colder days, and consider using lamps that emit UVB light, in consultation with a doctor. It is also crucial to educate the public about the importance of vitamin D not only for bones, but also for immunity, proper muscle function, psyche and metabolism. Effective prevention is a combination of knowledge, informed daily choices, and a personalized approach to health, which helps maintain normal vitamin D levels and minimize the risk of complications associated with vitamin D deficiency throughout the year.
Recommendations for supplementation and healthy lifestyle
Vitamin D supplementation should be tailored individually, taking into account age, body weight, lifestyle, climatic conditions and current blood levels of vitamin D. According to the current guidelines of the Polish Society of Endocrinology and other scientific societies, prophylactic supplementation is especially recommended during autumn and winter, when cutaneous synthesis of this vitamin in our climate is severely limited. For healthy adults, vitamin D intake of 800-2000 IU per day is recommended, but higher doses may be needed in obese, elderly, chronically ill or those with malabsorption disorders, but not exceeding the recommended maximum without medical supervision. In children and adolescents, pregnant women and the elderly, specific doses should be selected after medical consultation, and regular testing of 25(OH)D levels allows assessment of the effectiveness and safety of supplementation. The quality of the preparations used is also important – it is advisable to choose tested ones containing the declared dose of vitamin D3 (cholecalciferol), preferably in a fat-soluble form, which increases bioavailability. Supplementation should be introduced thoughtfully – both too low and too high levels of vitamin D can carry negative health consequences, such as hypercalcemia, kidney disorders and heart problems. If a deficiency is detected, the supplementation strategy should be to replace the initial deficiency and gradually move to maintenance doses, which should be done under the constant supervision of a specialist.
In a healthy lifestyle aimed at maintaining optimal vitamin D levels, it is crucial to have regular and controlled exposure to sunlight, which – despite Poland’s temperate climate – allows for effective synthesis of this substance during the summer months. It is recommended to be in the sun every day for a minimum of 15-20 minutes, between 10 am and 3 pm, with uncovered forearms and shins, but avoiding burns and overexposure to UV rays, especially in children. During periods with limited sunlight, it is advisable to introduce products rich in vitamin D into the daily diet, such as fatty marine fish (salmon, mackerel, sardines), cod liver oil, eggs and dairy products enriched with this vitamin. For vegetarians and people with lactose intolerance or allergies to milk proteins, vegetable drinks and margarines enriched with vitamin D are also recommended. In people who are particularly susceptible to deficiency, i.e. the elderly, those with darker complexions, reduced mobility, chronic gastrointestinal diseases or those taking certain medications that inhibit vitamin D absorption (e.g. certain antiepileptic drugs, glucocorticosteroids), it is advisable to conduct physical activity outdoors and closely monitor levels of this vitamin. An important element of prevention is also to avoid excessive use of high UV filters on a daily basis, if not necessary for dermatological reasons – filters significantly reduce vitamin D synthesis. When choosing a lifestyle, it is worth remembering the role of a balanced diet, maintaining a healthy body weight and taking care of healthy intestinal microflora, which can affect vitamin absorption. Spreading awareness of the consequences of vitamin D deficiency, the need for regular checkups and adjusting supplementation as needed, as well as promoting physical activity and nutritional education, are activities that realistically translate into improved health for entire populations. Incorporating these recommendations into daily life not only promotes the maintenance of adequate vitamin D levels, but also contributes to an overall improvement in immunity, fitness, bone health, muscle health and mental well-being.
Summary
Vitamin D deficiency can lead to a number of serious health problems, such as chronic fatigue, lowered immunity and muscle and bone pain. Regular monitoring of levels of this vitamin, a healthy diet and adequate sun exposure are key to maintaining good health and preventing deficiencies. In case of doubt or the appearance of worrisome symptoms, it is worthwhile to use laboratory diagnostics and consult a doctor about possible supplementation. Take care of your health and do not underestimate the role of vitamin D in the daily functioning of the body.
