Vitamin D Facts & Calcium - Vegan Nutrition with Marty Davey

Why do I always hear about Vitamin D and Calcium absorption? Are they linked with bones?

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This is going to be very boring and technical. On the other hand, it's a good question and I don't want to give a fluff answer. We always think of vitamin D and bones, but vitamin D does more than that; however, I'll stick to the "bones" material because I don't want to write a book.

Vitamin D assists with bone development in at least three ways. The first is in genetics.

Vitamin D3 assists in the genetics of bone formation with coding our messenger RNA [ mRNA]. Calcitriol, [another name for vitamin D3], reacts in the nucleus of a cell to create messenger RNA [mRNA], specifically the promoter region of a gene. Think of the promoter regions as an old printing office where there are two printing presses. The presses are across the room from each other. A printing plate would be created for the text to be printed. A "messenger" would help create the second plate, and make it exactly like the first. Also the messenger would take the second plate to the second printing press to print the same text. The messenger is messenger RNA [mRNA]. The mRNA brings the "printing plates" for synthesizing proteins that increase absorption of calcium.

Without vitamin D3, our genetic copy machine would be printing out paper with black smudges instead of readable text.

Secondarily, this genetic promotion stimulates formation of an important bone protein, Osteocalcin. You may remember that Osteo- means bone. Osteocalcin is the chief noncollagenous protein of bone matrix, and leads to bone development. Evidence shows that without vitamin D3 [calcitriol] it's just not going to happen.

Although the exact job of osteocalcin is not specifically known, we do know that osteocalcin is made by osteoblasts. Osteoblasts are cells that make bone cells. One way to remember the word, osteoblast is by thinking blasting out, or forming new bone cells. Stimulating the creation of bone cells is going to increase bone health. Osteocalcin is also used to specify bone health by measuring how much is present in your circulatory system.

Lastly, the presence of vitamin D3 itself signals calcium absorption in the intestines. This process of intestinal absorption is called transcaltachia.3 Transcaltachia is separate from the genetic use of calcitriol for calcium absorption. Your body has a whole electronic system that does a number of jobs including calcium absorption. The specific electronic impulse, assisted by calcitriol, opens calcium channels and allows the calcium to enter.

Now that your head is spinning, here's the take home message—the presence of vitamin D3 at the time of calcium absorption in the intestines directly increases absorption [transcaltachia], and indirectly increases absorption through cellular genetics [mRNA and osteocalcin].

Marty Davey is a Registered Dietitian and has a Masters degree in Food and Nutrition from Marywood University. She became a vegetarian in 1980 when she discovered that the chemicals in American meat made them unsellable to Europeans. She and her husband have raised their son as a vegan. She teaches nutrition and has a private practice specializing in assisting clients transitioning to a plant-based regime step by step. Her website is martydavey.com

Get your own personal nutrition consultation with Marty here.

Disclaimer: The advice given here is for eductional purposes only. You should not use this information to diagnose or treat a health problem or disease without consulting with a qualified health care provider.

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