Calcium homeostasis vitamin
In calcium homeostasis vitamin D plays an essential role It aids in the
- Absorption
- Utilization
- Regulation of calcium in the body
- Absorption:
- Vitamin D enhances the absorption of calcium from the intestines into the bloodstream.
- In the small intestine, vitamin D stimulates the production of calcium-binding proteins that facilitate the transport of calcium across the intestinal cells.
- This promotes efficient calcium absorption and helps maintain adequate calcium levels in the body.
- Reabsorption:
- Vitamin D influences the reabsorption of calcium in the kidneys.
- It acts on the renal tubules, promoting the reabsorption of filtered calcium back into the bloodstream.
- This reduces the loss of calcium through urine, conserving it for essential bodily functions.
- Bone Health:
- It assists in the proper mineralization of bones by facilitating the absorption and utilization of calcium.
- In the absence of sufficient vitamin D, the body may struggle to absorb calcium efficiently, leading to weakened bones, increased risk of fractures, and conditions like rickets in children and osteomalacia in adults.
- Vitamin D as a regulator :
- Vitamin D regulates the production and secretion of parathyroid hormone (PTH), which is involved in calcium homeostasis.
- Adequate vitamin D level helps maintain a balance between calcium and PTH.
- When blood calcium levels are low, vitamin D suppresses PTH secretion, reducing the release of calcium from bones and promoting calcium absorption from the intestines.
- Calcium Storage:
- Vitamin D assists in the deposition of calcium into the bones, promoting their strength and integrity.
- It helps ensure that calcium is stored properly in the bone matrix, maintaining a reservoir of calcium for when it is needed by the body.
- Insufficient levels of vitamin D can lead to impaired calcium absorption and utilization, resulting in decreased calcium levels in the body.
- This can contribute to conditions like osteoporosis, muscle weakness, and increased risk of fractures.
| Vitamin | Recommended Amount (Daily) | Role | Sources |
| Vitamin D
| 600-800 IU (International Units)
| · Enhances calcium absorption · Promotes calcium reabsorption in the kidneys · Aids in bone health | · Sunlight exposure (UVB rays) · Fatty fish (e.g., salmon, mackerel) · Fortified dairy products · Egg yolks |
| Vitamin K | 90-120 mcg | · Supports bone mineralization · Assists in calcium binding to bone proteins | · Leafy green vegetables (e.g., spinach, kale) · Broccoli · Brussels sprouts · Fermented foods |
| Vitamin C | 75-90 mg | · Plays a role in collagen synthesis which is essential for bone formation | · Citrus fruits (e.g., oranges, lemons) · Strawberries · Bell peppers · Broccoli |
| Vitamin B6 | 1.3-1.7 mg (Adults) | · Participates in the conversion of amino acids involved in bone metabolism | · Poultry · Fish · Bananas · Potatoes · Chickpeas |
| Vitamin B12 | 2.4 mcg (Adults) | · Supports bone cell activity and mineralization | · Animal products (e.g., meat, fish, dairy) · Fortified cereals |