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Vitamin D, please.

This week the topic is Vitamins and we were asked to focus on One Vitamin and I chose Vitamin D!

2. Discuss the issue of vitamin supplementation by choosing ONE vitamin to discuss.

a. What role does biochemical individuality play in determining nutrition needs?

b. What are life-cycle and lifestyle factors that may increase the need for supplementation?

c. What would you consider an appropriate level of supplementation?

As I have mentioned before I supplement B12 due to my being vegan currently, but vegetarian since 1988 and my B12 stores were depleted. But also at the same time I was told to start supplementing Vitamin D. So I wanted to do some research on Vitamin D and see what it told me.

“Vitamin D deficiency is regarded as a public health issue [1,2], as approximately 40% of the general population in Europe and 25% in the United States show 25-hydroxyvitamin D [25(OH)D] serum concentrations below 50 nmol/L (divide by 2.496 to convert nmol/L to ng/mL) [3e5]. Since the vitamin D receptor (VDR) regulates approximately 3% of the human genome, studies in recent years focused on extra-skeletal (i.e., non-classical) effects of vitamin D in addition to the well-known (classical) effects on bone health [6,7]. Indeed, vitamin D deficiency was associated with several adverse health outcomes including impaired glucose tolerance and female infertility [8]” (Trummer, Theiler-Schwetz, Kollman, et al. 2019).

“In this trial in 150 healthy premenopausal women with baseline 25(OH)D serum concentrations below 75 nmol/L, vitamin D supplementation had no significant effect on AUCgluc at study end (24 weeks). Regarding secondary outcome parameters, supplementation with cholecalciferol had a significant adverse treatment effect on HOMA-IR and QUICKI, while there was no significant treatment effect on any of the remaining parameters including various sex steroid hormones at study end. Vitamin D supplementation had no significant effect on any of the primary or secondary outcome parameters after 12 weeks. The rationale of our study, i.e. to investigate the effect of vitamin D supplementation in healthy premenopausal women, is of general interest and importance when considering the widespread use of vitamin D supplements in the general population. For example, data from a national survey in the United States documented that 18.2% of the general population used a daily vitamin D supplementation of 1000 IU or more in 2013e2014 [30]. The prevalence of vitamin D supplementation of more than 4000 IU daily was 3.2% in these years [30], therefore exceeding the supplementation dose used in the present study. Thus and in view of the ubiquitous expression of the VDR [6], especially in tissues involved in hormonal regulation and homeostasis, a thorough investigation of vitamin D supplementation.” (Trummer, 2019).

My blood work was what told my doctor I needed to supplement my Vitamin D.

From our textbook “Advancing age also decreases the ability of the skin to produce vitamin D. Thus, older adults are encouraged to consume extra vitamin D from fortified foods or dietary supplements.” (Nix, 2017).

“Healthy adults who consume well-balanced and varied diets do not require mineral supplements. A wellrounded and varied diet in combination with adequate physical activity and exercise maintains optimal bone health in most adults. Studies do indicate that supplemental calcium and vitamin D improve bone health and reduce the risk of fracture among postmenopausal women.” (Nix, 2017).

“Vitamin D and calcium are essential nutrients for growth and for the maintenance of healthy bone tissue.” (Nix, 2017).

“Some researchers believe that about half of the elderly population worldwide is deficient in vitamin D and warrants supplementation.22 Yet, as discussed in Chapter 7, the measurement tools for assessing vitamin D status and the parameters for normal versus deficient status are not universally accepted. It is routine to screen individuals at risk for vitamin D deficiency; however, it is not recommended to screen for vitamin D deficiency in asymptomatic adults because the cost of doing so is not justified.23

The DRIs for vitamin D are 600 IU/day for individuals who are between 1 and 70 years old and 800 IU/day for individuals who are older than 70 years of age.24 To meet the dietary recommendation for vitamin D, elderly individuals should consume foods

that are fortified with vitamin D or take a dietary supplement to overcome the reduced ability to endogenously synthesize vitamin D. Individuals living in nursing homes or other situations with little to no sunlight exposure, who avoid dairy products (which are

good sources of vitamin D), or who are obese may benefit from vitamin D evaluation to determine the need for supplementation. Supplementing with vitamin D in older or institutionalized adults may reduce the risk of falls, although not necessarily the risk of fracture, but other health benefits are inconclusive.” (Nix, 2017)

“While it is rare that a multivitamin/mineral supplement, or the previously mentioned individual supplements of vitamins B12 or D, would result in toxicity it is always recommended to report and discuss the use of dietary and herbal supplements to health care providers.” (Nix, 2017).

As our textbook points out several factors, elderly persons who don’t get a lot of sun need the supplement. Our textbook also suggests the appropriate amount of supplement.

Considering my limit to sunshine that might be another reason I am supplementing with Vitamin D. I just figured it was something most people had to take. The initial research cited above does state it is a public health concern that people are deficient in Vitamin D.

Let’s end with an illustration about how our body processes Vitamin D.

This image if from (Nix, 2017).


Trummer C, Theiler-Schwetz V, Kollmann M, et al. Effects of vitamin D supplementation on metabolic and endocrine parameters in healthy premenopausal women: A randomized controlled trial. Clinical Nutrition. 2020;39(3):718-726. doi:10.1016/j.clnu.2019.03.007.

Nix, S. (2017). Williams’ Basic Nutrition and Diet Therapy (15th ed.). Maarssen, Netherlands: Elsevier Gezondheidszorg.

Thank you for reading!

#vitamind #sun #healthytips #healthyhabits #mentalhealth #healthyhabits #health #healthychoices #healthjourney #hearthealth #healthylifestyle #healthcoach #mastersprogram #eatwell #supplements #sunshine #bonehealth #kidneyhealth

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