Antarctic Scientists got less than 150 IU of vitamin D daily - Aug 2015

Vitamin D levels in German Antarctic - Dec 2015

Changes of 25-OH-Vitamin D during Overwintering at the German Antarctic Stations Neumayer II and III.
PLoS One. 2015 Dec 7;10(12):e0144130. doi: 10.1371/journal.pone.0144130. eCollection 2015.
Steinach M1, Kohlberg E2, Maggioni MA1,3, Mendt S1, Opatz O1, Stahn A1, Tiedemann J1, Gunga HC1.
1Center for Space Medicine and Extreme Environments Berlin, Institute for Physiology, Charité Universitätsmedizin Berlin, Berlin, Germany.
2Alfred Wegener Institute for Polar and Marine Research, Bremerhaven, Germany.
3Department of Biomedical Sciences for Health, Università degli Studi di Milano, Milan, Italy.

PURPOSE:
Humans in Antarctica face different environmental challenges, such as low ultra-violet radiation, which is crucial for vitamin D production in humans. Therefore we assessed changes in 25-OH-vitamin D serum concentration during 13 months of overwintering at the German Stations Neumayer II and III (2007-2012). We hypothesized that (i) 25-OH-vitamin D serum concentration would significantly decrease, (ii) changes would be affected by age, gender, baseline (i.e. pre-overwintering) fat mass, baseline 25-OH-vitamin D serum concentration, and station residence, and (iii) our results would not differ from similar previous studies in comparable high latitudes.
MATERIALS & METHODS:
25-OH-vitamin D serum concentrations were determined before, after, and monthly during the campaigns from venous blood samples of n = 43 participants (28 men, 15 women). Baseline fat mass was determined via bio impedance analysis and body plethysmography. Data were analyzed for change over time, dependency on independent parameters, and after categorization for sufficiency (>50nmol/l), insufficiency (25-50nmol/l), and deficiency (<25nmol/l). Results were compared with data from similar previous studies.
RESULTS:
We found a significant decrease of 25-OH-vitamin D with dependency on month. Age, gender, fat mass, and station residence had no influence. Only baseline 25-OH-vitamin D serum concentrations significantly affected subsequent 25-OH-vitamin D values.
CONCLUSIONS:
Overwinterings at the Antarctic German research stations Neumayer II and III are associated with a decrease in 25-OH-vitamin D serum concentrations, unaffected by age, gender, baseline fat mass, and station residence. Higher baseline vitamin D serum concentrations might protect from subsequent deficiencies. Residence at the Neumayer Stations may lead to lower vitamin D serum concentrations than found in other comparable high latitudes.

PMID: 26641669
 Download the PDF from Vitamin D Life

---

Dietary intakes of expeditioners during prolonged sunlight deprivation in polar enviroments do not support bone health

Int J Circumpolar Health. 2015 Aug 6;74:27965. doi: 10.3402/ijch.v74.27965.
Iuliano S1 , Ayton J 2.

BACKGROUND: Early Antarctic expeditions were plagued by nutrient deficiencies, due to lack of fresh food and reliance on preserved foods. Modern Antarctic expeditioners also require provisions to be shipped in, but improved knowledge and storage options ensure foods are nutritionally sound. Despite this, nutritional imbalances are observed.

OBJECTIVES: To determine the adequacy of dietary intake of Antarctic expeditioners, with reference to bone health.

DESIGN: Dietary intake was determined on 225 adults (mean age 42±11 years, 16% female) during 12-month deployments at Australian Antarctic stations from 2004 to 2010, using weighed 3-day food records. Nutrient intake was analysed using FoodWorks. Foods were divided into the 5 food groups according to the Australian Guide to Healthy Eating.

RESULTS: Men consumed below the recommended levels [recommended daily intake (RDI)/adequate intakes (AI)] of

• calcium (79±42% of RDI, p<0.001),
• magnesium (83±34% of RDI, p<0.001),
• potassium (86±29% of AI, p<0.001) and
• fibre (75±30% of AI, p<0.001),

and above the upper limit (UL) for

• sodium (125±48% of UL p<0.001), w

hereas women consumed below the recommended levels of calcium (68±21% of RDI, p<0.001) and iron (73±37% of RDI, p<0.001). Vitamin D intake is not substantial (<150 IU/d). Men consumed more alcohol than women (18±24 g/d vs. 10±13 g/d, p<0.05), nearer the guideline of ≤20 g/d. Men and women consumed approximately 1 serving of dairy food per day, and 3 of 5 recommended vegetable servings. Discretionary foods were consumed in excess of recommended.

CONCLUSIONS: Improving consumption of calcium-rich (dairy) foods better supports bone health during sunlight deprivation. Increasing vegetable intake to recommended levels will increase fibre, potassium and magnesium intakes. The challenge is the logistics of providing these foods throughout the year.

PMID: 26253749

---

See also Vitamin D Life

• The only supplement NASA gives crews is vitamin D - Sept 2015
• Recommended increasing vitamin D for space flight – NASA Sept 2013
• Submariners vitamin D levels continued to drop while on patrol (no surprise) – Dec 2013
• People with no UV for 6 months in the winter need at least 2000 IU of vitamin D – April 2011
• 1700 IU vitamin D (50000 monthly) helped antarctic explorers – RCT Jan 2012
  The study on this page seems to have not read the Jan 2012 study
• Many reasons why vitamin D deficiency has become epidemic the main one = not getting enough sunshine
• Vitamin D Supplementation in Underway Submariners file
• All items in category Shut-ins and Vitamin D 32 items