Lack of Vitamin D: Symptoms

Tap to Read ➤ Rahul Thadani

Vitamin D is a fat-soluble vitamin that plays a major role in calcium metabolism and bone growth. Deficiency of this vitamin leads to bone and joint pain, muscle pain, weakening and softening of bones, etc. This story provides more information about the skeletal and non-skeletal symptoms indicative of a lack of vitamin D.

Vitamin D is essential for calcium metabolism and bone growth, as well as for maintenance of mental health in children and adults. Around 80% of the vitamin D requirement of our body is fulfilled through its synthesis from cholesterol in a sunlight-dependent manner, and hence it is also known as the 'sunshine vitamin'. The dietary sources of this vitamin are very few, and mainly include oily fish like salmon, mackerel and herring.

Reduction in the levels of vitamin D, or hypovitaminosis D, may occur due to limited exposure to sunshine, defects in the synthesis and absorption processes or due to insufficient dietary intake. The initial symptoms arising due to a lack of vitamin D include fatigue, bone and joint pain, muscle aches and twitching, etc. Prolonged deficiency leads to rickets and osteomalacia which are known as the classical vitamin D deficiency diseases.

Given here is a brief description of this vitamin followed by a detailed account of the consequences of vitamin D deficiency with a special emphasis on their signs and symptoms.

About Vitamin D

► Structure and Forms Vitamin D is a fat-soluble vitamin and is structurally similar to steroids. Vitamin D2 (ergocalciferol) and vitamin D3 (cholecalciferol) are the two prevalent forms of vitamin D, and are present in the dietary sources. In the human body, vitamin D3 is synthesized in the skin from a molecule called dehydrocholesterol, by the action of UVB (ultraviolet B) photons.

► Dietary Sources D2 : Mushrooms, lichens and alfalafa D3 : Fattly fish like salmon, mackerel, herring and sardines; liver oils from cod, tuna and shark; milk and dairy products; egg yolk

► Importance Vitamin D3 is converted to its active form called calcitriol by a set of reactions that occur in the liver, kidneys as well as certain white blood cells.

Calcitriol acts through vitamin D receptors present in various organs, and is involved in: Calcium absorption from intestine Calcium reabsorption from bones Maintaining calcium and phosphorus levels of blood Modulation of immune response during microbial infection Regulating cellular proliferation and differentiation in several tissues.

Lack of Vitamin D

Initial Signs and Symptoms Fatigue Muscle ache Muscle twitching Bone and joint pain Mood swings Hypocalcemia

Vitamin D being a crucial component of several vital processes including bone mineralization, its deficiency leads to skeletal as well as non-skeletal health issues. These are explained ahead:

Skeletal Problems

Lack of vitamin D results in lowered absorption of calcium from the intestines, which in turn leads to low amounts of calcium in blood. In order to cope with this, calcium is reabsorbed from the bones (through the action of parathyroid hormone) thereby leading to reduced bone mineral density (osteopenia). This leads to the following health issues:

► Rickets It refers to the skeletal deformities occurring in children owing to a deficiency or malabsorption of vitamin D or calcium or phosphate. It leads to softening of bones and delayed dental growth . The child has low muscular strength, and often tires out easily.

The normal skeletal growth of children gets hampered resulting in a short stature. Other signs and symptoms include: Wrist widening Odd-shaped skull Spinal cord deformities Outward curving of legs Abnormal gait Dental deformities

► Osteomalacia The softening of bones in adults, occurring due to vitamin D deficiency is termed as osteomalacia. It is characterized by widespread bone pain , especially in the hips, along with low calcium levels .

In addition, the individual may experience: Numbness in the limbs Numbness near the mouth Muscle spasticity Bending of bones Easy fractures without any injury

► Poor Oral Health Low vitamin D is associated with tooth loss and dental caries . Apart from maintaining dental strength, vitamin D is also responsible for the production of defensins, that help to combat oral infections.

Hence, low amounts of this vitamin increases the susceptibility to gum infections, and leads to gum inflammation , gum tenderness and bleeding gums .

Non-skeletal Problems

Vitamin D serves as an important functional component of the neural system, immune system as well as the endocrine system of the body. Hence, its deficiency results in the following non-skeletal health concerns as well.

► Winter Blues Mood swings, depression and general malaise can be attributed to the lack of vitamin D. It is also one of the causes for Seasonal Affective Disorder (SAD), a disorder characterized by depressed mood during winters.

Other symptoms include: Social withdrawal Hopelessness Irritability Lethargy Suicidal tendencies (in extreme cases)

► Sleep Disorders Hypovitaminosis D has been identified as the etiology behind several sleep disorders, owing to the presence of vitamin D receptors in the brain tissue associated with sleep. These include: Insomnia Sleep apnea (disturbed breathing during sleep) Somniloquy (talking while asleep) Excessive daytime sleeping

► Neurological Problems Lack of vitamin D has been identified as one of the reasons behind poor cognitive development in children, and lowered cognitive functions in adults. It is also one of the etiological factors for dementia characterized by: Forgetfulness Confusion Loss of social skills Poor judgment Difficulty in performing regular tasks

► Compromised Immunity In addition to the several roles performed by this vitamin, it also regulates the production of chemical messengers of the immune system as well as the activation of certain immune cells.

It is serves an important component of the innate immune system by regulating the production of antimicrobial peptides in the skin. Being so, low vitamin D levels render the individual more susceptible to colds, skin infections including staph infections, and even respiratory tract infections .

► Secondary Hyperparathyroidism Parathyroid glands are tiny oval-shaped glands present near the thyroid gland, and are responsible for the synthesis and production of parathyroid hormone. This hormone plays an important role in the maintenance of blood calcium levels.

Low vitamin D levels leads to decreased levels of calcium , which in turn causes increased secretion of parathyroid hormone . Such increased amounts of parathyroid hormones in response to hypocalcemia is known as secondary hyperparathroidism. The symptoms include: Nausea Vomiting Abdominal pain Loss of appetite Forgetfulness Frequent urination

Low Vitamin D in Elderly Reduction in bone density is a natural phenomenon in the elderly. Lack of vitamin D further aggravates this condition leading to several bone problems, and increases the risk of osteoporosis and arthritis.

Other problems associated with hypovitaminosis D in the elderly are as given below: ► Neurological Problems Low levels of vitamin D during old age leads to several neurological and neuromuscular problems, and is also associated with an increased risk for Alzheimer's disease.

The symptoms of such neurological problems include: Postural instability Falls Cognitive impairment Lowered concentration Indecisiveness Reduced appetite

► Temporary Hearing Loss Lack of vitamin D is also one of the reasons behind hearing loss in the elderly, which can be partially reversed through vitamin D supplementation. This can be attributed to the demineralization of bones present in the middle ear, which affects the communication between eardrums and brain.

Causes of Low Vitamin D

The active and functional form of vitamin D is derived through a variety of processes, and hence low levels of the active form can be the result of: Minimal exposure to sunlight Dietary inadequacy Chronic kidney failure Lowered absorption of vitamin D from the intestines Hyperpigmentation and dark skin color Excessive use of sunblocks Hereditary factors Old age

Vitamin D plays a versatile role as far as the normal growth and development of an individual is concerned. Being so, the arena of vitamin D supplementation is being explored with respect to the different health issues that can be partially addressed, if not cured, with the help of this vitamin.

Disclaimer : This Health Story is for informative purposes only, and should not be used as a substitute for professional medical advice.