Vitamin D in 7 minutes - video & summary

Vitamin D in 5 minutes – everything you really need to know!

YouTube - Dec 2025

Summary — "Vitamin D in 5 Minuten" (German, ~7 min of content)

  • (00:00) Vitamin D is presented as a hormone that, at Central European latitudes, can only be made from about April to September, between 11:00 and 15:00, with ~40% of skin uncovered, for ~20 minutes, without sunscreen — yielding roughly 15,000–20,000 IU.
    * Note: only if light-skinned and young

  • (00:23) Outside that window, skin synthesis is effectively nil; fatty sea fish contributes only a little, so supplemental drops are the practical route.

  • (00:51) It regulates roughly 2,000 genes and is used by every cell (brain, bone, muscle, immune system), so the century-old 20 ng/mL bone-disease threshold is treated as obsolete.
    * Note: Lower vitamin D levels activate fewer genes

  • (01:12) Suggested maintenance: ~1,000 IU per 10 kg body weight (80 kg → 8,000 IU/day), more under physical or mental stress — but two people of the same weight can need very different amounts depending on body fat and metabolism, so testing is required.

  • (01:34–02:11) Testing via doctor or pharmacy; most people will find themselves deficient (<30 ng/mL, sometimes 6–7). Correction: about 4 weeks at two to three times the maintenance dose (~20,000 IU/day at 80 kg).
    * Note: Should wait for 3 months after supplementing before testing

  • (02:11) Co-factors: vitamin K2 to keep calcium out of blood vessels, magnesium to allow conversion to the active form in liver and kidney.
    * Note: Vitamin D Cofactors in a nutshell

  • (02:48–03:18) Contraindications: skip K2 on warfarin or phenprocoumon (K2 antagonists); avoid supplemental D in sarcoidosis, certain lymphomas, and other granulomatous conditions where the body produces its own D and calcium can rise.

  • (03:18–03:42) Deficiency has no single signature — commonly low mood, pain, ongoing inflammation, recurrent infections, and, because every cell can respond, knee/thigh/back pain, headaches, migraine.

  • (04:08–05:00) Target range 50–150 ng/mL, with 60–100 called the healthiest zone; toxicity risk above 150 comes from increased calcium absorption rather than the D itself, and K2 mitigates that. Overshoot is handled by simply pausing or reducing for weeks to months; first symptom of excess is typically nausea, then a calcium check.

  • (05:31–06:21) You cannot be allergic to vitamin D — intolerance points to the formulation, so switch preparations. Weekly or biweekly high-dose bolus dosing is discouraged as it swings the hormone and calcium balance; take a daily maintenance dose instead. Skin synthesis worsens with age, making the (~€2/month) drops more important over time.
    * Note: about 1 in 10,000 people are allergic - Vitamin D accumulates if a specific poor gene

  • (07:05) Closing "big three": strength/movement training, 30–40 mL fluid per kg per day (??), and a D level of 60–100 ng/mL.


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