Vitamin D is a fat-soluble vitamin known as the "sunshine vitamin" because the skin produces it when exposed to sunlight. It plays a crucial role in maintaining strong bones by aiding in the absorption of calcium and phosphorus. Vitamin D also supports the immune system, cell growth, and brain health. Dietary sources include fatty fish, egg yolks, and fortified foods, and supplements are available when sun exposure is limited. Both deficiency and excess can have health implications, so it's important to maintain an appropriate balance. IC Fitness Club, an institute of Fitness Science, founded by Deepak Bhardwaj with the aim to provide best educational and knowledgeable fitness courses to the gym trainers. Deepak Bhardwaj, The Principal, has been teaching the students since 2016 and founded IC Fitness Club ® - Best Personal Trainer Course in Delhi and Sports Nutrition Course in Delhi Address: B-5, 1st floor, above Fed Bank, Dwarka Mor, Patel Garden, New Delhi, Delhi 110078 Phone: 088514 19719 https://www.icfitnessclub.com/

1. Vitamin-D
Functions, RDA,
Deficiency and Health
Issues
By IC Fitness Club - An Institute of Fitness Science

2. Functions of Vitamin D
Deficiency of Vitamin D & Health Issues
RDA of Vitamin D
1
3
2
CONTENTS
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3. Vitamin D (Introduction &
Function)
Vitamin D is a fat-soluble vitamin that plays a crucial role in several vital functions
within the human body. There are two primary forms of vitamin D: vitamin D2
(ergocalciferol) and vitamin D3 (cholecalciferol). Vitamin D3 is synthesized in the skin
when exposed to ultraviolet B (UVB) radiation from sunlight, while vitamin D2 is
obtained from certain plant-based foods or supplements.
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4. FUNCTIONS OF VITAMIN D
• Calcium and Phosphorus Absorption: One of the main functions of vitamin D is
to enhance the absorption of calcium and phosphorus from the intestine. This
process is essential for maintaining proper bone health and mineralization,
preventing conditions like rickets in children and osteomalacia in adults.
• Bone Health: Vitamin D helps regulate the levels of calcium in the blood by
promoting its absorption from the gut and reabsorption from the kidneys. It
also facilitates the deposition of calcium in bones, making them stronger and
less prone to fractures.
• Cardiovascular Health: Emerging research indicates that vitamin D may have a
positive impact on cardiovascular health by helping to regulate blood pressure,
reduce inflammation, and improve overall heart function.

5. • ....CONTINUED
• Immune System Support: Vitamin D is involved in the modulation of the immune system, helping it to
function efficiently and respond appropriately to infections and diseases. It has been associated with a
reduced risk of autoimmune diseases and may also play a role in reducing inflammation.
• Muscle Function: Some research suggests that vitamin D is important for maintaining muscle strength
and function, which can be particularly significant in preventing falls and improving physical
performance, especially in older adults.

6. RDA(recommended Dietary Allowance) OF
VITAMIN D
The Recommended Dietary Allowance for adults 19 years and older is 600 IU (15 mcg) daily for men and
women, and for adults >70 years it is 800 IU (20 mcg) daily.
Sources of Vitamin D
• Sunlight: The most natural and significant source of vitamin D is sunlight. When your skin is exposed to
UVB rays from the sun, it synthesizes vitamin D3. The amount of vitamin D produced depends on factors
such as skin pigmentation, geographic location, time of day, and season.
• Foods: Some foods contain vitamin D, but it is not present in a wide variety of foods naturally. Fatty fish
(salmon, mackerel, tuna), fish liver oils, beef liver, egg yolks, and fortified foods like milk, orange juice, and
cereals are some dietary sources of vitamin D.
• Supplements: Vitamin D supplements are available in various forms, including vitamin D2 and D3, and are
commonly used to ensure adequate intake, especially in individuals who may have limited sun exposure or
dietary sources.

7. Deficiency of Vitamin-D & Health Issues
• Osteoporosis and Osteomalacia: Weak bones and fractures.
• Rickets: Soft and weak bones in children.
• Muscle Weakness and Pain: Weak muscles and increased risk of falls.
• Immune System Impairment: Increased susceptibility to infections.
• Cardiovascular Problems: Higher risk of heart diseases.
• Mood Disorders: Increased risk of depression and anxiety.
• Autoimmune Diseases: Linked to conditions like multiple sclerosis and
rheumatoid arthritis.

8. Thank you
by
IC Fitness Club - An Institute of Fitness Science
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