What Happens When Your Vitamin D Is Low?

Vitamin D is a fat-soluble vitamin that plays an important role in several functions within the body. 

It exists in two main forms: vitamin D2 (ergocalciferol) and vitamin D3 (cholecalciferol). Vitamin D2 is derived from plant sources, while vitamin D3 is primarily synthesised in the skin when it is exposed to sunlight and can also be obtained from animal-based food sources.

What Does Vitamin D Do In Your Body And What Happens If You Don’t Have Enough?

Vitamin D deficiency can lead to a variety of symptoms that vary in severity depending on the extent of the deficiency. 

Vitamin D Helps Maintain Healthy Muscles And Bones

Vitamin D is essential for maintaining healthy bones and muscles, which reduces the risk of fractures and osteoporosis. 

It helps regulate the absorption of calcium and phosphorus in the intestines and promotes the deposition of calcium and phosphorus into the bones, contributing to bone mineralisation and density.

Adequate vitamin D levels are associated with improved muscle strength and function, reducing the risk of falls (and thereby also the risk of fractures) and improving physical performance. 

Calcium is essential for muscle contraction, and vitamin D helps ensure an adequate supply of calcium is available for muscle cells. Without sufficient vitamin D, calcium absorption from the intestines is reduced, which can lead to decreased calcium levels in the blood and impaired muscle function.

Additionally, vitamin D helps regulate muscle protein synthesis, which is the process by which muscle cells build and repair proteins necessary for muscle growth and strength. 

Feeling tired is a common symptom of vitamin D deficiency. You may experience overall weakness and find it difficult to perform daily activities. 

Vitamin D deficiency can also lead to bone and muscle pain, including back pain, joint pain, and muscle aches. In severe cases, it can contribute to conditions like osteoporosis or osteomalacia, which are characterised by weakened bones.

Vitamin D Prevents Rickets And Osteomalacia

Vitamin D is crucial for preventing conditions like rickets in children and osteomalacia in adults. 

Rickets is a bone disorder primarily affecting children that results from a deficiency in vitamin D, calcium, or phosphate. It causes the bones to become weak, soft, and deformed, leading to skeletal deformities, growth impairments, and an increased risk of fractures. 

Rickets can occur due to inadequate sunlight exposure, insufficient dietary intake of vitamin D and calcium, malabsorption issues, or certain medical conditions. It is preventable through proper nutrition, sunlight exposure, and, in some cases, vitamin D supplementation.

Osteomalacia is a condition characterised by the softening and weakening of the bones. It is primarily caused by a deficiency in vitamin D, calcium, or phosphate, which leads to impaired mineralisation of bone tissue. 

Unlike rickets, which affect children, osteomalacia occurs in fully grown adults. It can result from factors such as insufficient sunlight exposure, inadequate dietary intake of vitamin D or calcium, certain gastrointestinal disorders that affect nutrient absorption, or kidney diseases that impair the conversion of vitamin D into its active form. 

Common symptoms include bone pain, muscle weakness, and an increased risk of fractures. Treatment typically involves addressing the underlying nutritional deficiencies and, if necessary, providing vitamin D and calcium supplementation.

Vitamin D Supports The Immune System

Vitamin D plays a role in supporting a healthy immune system. 

It modulates immune responses and helps defend against infections, including respiratory tract infections such as colds and flu. 

Vitamin D is also involved in regulating cell growth, proliferation, and differentiation. It plays a role in various cellular processes and may have implications for cancer prevention and other chronic diseases. 

Vitamin D also plays a role in the healing process, and deficiency can slow down wound healing and recovery from injuries or surgeries.

Vitamin D Helps Maintain Mental Health

Some studies suggest a link between vitamin D deficiency and mood disorders like depression and anxiety. Low vitamin D levels may contribute to feelings of sadness, low mood, or general emotional discomfort.

Although the exact mechanisms are not fully understood, vitamin D is believed to modulate the production and availability of serotonin, a neurotransmitter that plays a key role in regulating mood. Low levels of serotonin have been associated with conditions like depression, and vitamin D may help maintain optimal serotonin levels.

Vitamin D receptors are present in areas of the brain associated with mood regulation. Adequate levels of vitamin D may promote healthy brain function and protect against cognitive decline, which can indirectly contribute to improved mood.

Vitamin D also has anti-inflammatory properties and can help reduce inflammation in the body. Chronic inflammation has been linked to mood disorders, and by mitigating inflammation, vitamin D may have a positive impact on your mental health.

Seasonal affective disorder (SAD) is a type of depression that typically occurs during the winter months when exposure to sunlight is reduced. It is thought that decreased sunlight exposure leads to lower vitamin D levels, which may contribute to the development of SAD. Supplementing with vitamin D during these months may help alleviate symptoms.

Where Do We Get Vitamin D From?

There is a common misconception that vitamin D comes directly from the sun. 

While sunlight exposure does play a crucial role in the body's production of vitamin D, it is not the actual source of the vitamin itself. Vitamin D is a nutrient that the body synthesises when sunlight interacts with the skin, triggering a series of chemical reactions. 

Vitamin D can also be obtained from dietary sources such as fatty fish, fortified dairy products, and supplements.

While it is challenging to obtain sufficient vitamin D from diet alone, some foods naturally contain vitamin D or are fortified with it. 

Good food sources of vitamin D include fatty fish (such as salmon, mackerel, and sardines), cod liver oil, egg yolks, fortified dairy products (milk, yoghurt, cheese), fortified plant-based milk alternatives, and fortified breakfast cereals. The amount of vitamin D in these food sources can vary, so it's important to check labels and choose fortified options when possible.

In cases where sunlight exposure and dietary sources are insufficient, healthcare professionals may recommend vitamin D supplements. These supplements are available in both vitamin D2 and D3 forms and come in various dosages. If you think you may have a vitamin D deficiency or have concerns about your vitamin D levels, it's best to consult with a healthcare professional for appropriate supplementation recommendations.