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​ ​ ​ What I do instead & why this might not be right for everyone. My exact winter protocol & FAQS

The Vitamin D Debate..

In most health circles, vitamin D supplements are widely recommended, and the logic is: Your D3 is low - take more D3” - (and most good practitioners will also say “don’t forget K2 & magnesium.”)

However - one of the benefits of working 1:1 with people, as well as having access to almost half a million people across platforms, is that I get to see how this plays out in real bodies- not just theory on paper or social media soundbites.

And here’s the truth:

What works beautifully for one person can backfire for another. Especially when it comes to hormones, light, mitochondria, and seasonality.

So today I want to talk about my personal decision (and why it might not be right for you) - all the data, my personal protocol & common FAQS.

Keep reading for the full article....

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Quick disclaimer:

I’m not a doctor, and I’m definitely not your doctor. Use your judgment, your intuition, and your care team. Nothing here is fear-mongering - just physiology, data, and a different lens than you will find in most health circles.

I recently wrote an article on my vitamin D labs from this year at the end of spring & the beginning of fall (click here to read) - and a few reasons why people might find themselves "low" at the end of summer despite going outside.

So if you haven't read that deep dive - I highly recommend it before diving into this one. I also need to clarify that last winter - I did not use any UVB lamps - only red light therapy (as an experiment).

This winter I will be using my personal UVB lamp protocol (as I did start to feel quite low in February of this year - and want to see if this helps as it has in previous years) & will be drawing labs - so stay tuned!

The big misconception

Most people are taught: “Low number = take more pills.”, but my work says: start upstream- with light, timing, and mitochondria- because sunlight isn’t just “vitamin D.” UVB makes D₃ plus balancing photoproducts (e.g., lumisterol, tachysterol) that help regulate the whole system......and you can't necessarily hack that with supplements.

Why I personally skip routine vitamin D supplements in winter

I stopped taking vitamin D supplements in 2021 after speaking with Jim Stephenson Jr & diving into the research with him (click here to watch the interview).

If you join Jim's group on Facebook - there are hundreds of stories from people who have had negative health repercussions from supplementation.

I want to re-iterate that it was my personal decision to do this & I still want you - the reader - to look at all the information & decide what makes the most sense to you.

Here's some of my logic:

1. Trials don’t show broad magic. Raising 25-OH D with supplements hasn’t reliably improved major outcomes like fractures, CVD, or cancer incidence. See VITAL and others (PMIDs at the end of this article).
2. High-dose risks are real. Annual or monthly mega-doses increased falls and fractures in older adults (PMIDs at the end of this article).
3. Regulation matters. Skin-made D occurs with co-signals (UVA/UVB + red/IR, nitric oxide, melatonin rhythm) the pill can’t reproduce.
4. Context matters. Magnesium status, melatonin rhythm (sleep + darkness), circadian timing, and genetics all influence your numbers.

And when you truly dig into the research - the evidence right now leans more toward melatonin and circadian health (your light/dark cycles, sleep, and mitochondrial timing) being more consistently linked with cancer-protective effects than just taking vitamin D supplements alone.

That doesn’t mean vitamin D does nothing - it means:

Light → circadian rhythm → mitochondria → hormones (including D) is a system, and vitamin D is just one piece of it.

In other words: Instead of trying to fix everything with a vitamin D pill, we may get more benefit by improving the light and circadian inputs that regulate vitamin D and melatonin in the first place.

Click here for a 90 second video I recorded on Friday that explains more

What I do instead (my winter light stack)

1) The basics matter more than anything:

• Circadian health is fundamental & protecting my body's own melatonin production (click here for my most recent podcast on melatonin).
• Hydration is also key in winter (read my winter hydration article)
• Sleep & proper nutrition (click here for early black Friday on Leptin Diet for more help with your winter nutrition).
• In winter, dietary vitamin D provides substrate while DHA optimizes membrane phototransduction and vitamin D receptor signaling - together supporting circadian-immune function when UVB is low.
• Lowering stress - keeping NNEMF at bay as much as possible.
• Gentle cold exposure: There is some speculation that hypothesizes we can make vitamin D internally in response to cold
• More help - My Quantum Winter Blueprint (extended one more day)

2) Safe UVB in micro-doses - always paired with red/infrared & not medical advice:

• Start 1-2 minutes/side, 2–4x/week, build slowly to 5 minutes per side
• Eye protection is crucial for UV lamps, increase distance & go slower if you’re fair-skinned/sun-sensitive.
• I don't recommend going over 5 minutes per side & understand that the burn is "delayed" with UVB lamps - so you won't necessarily feel your skin getting warm like you do in the sun.
• Do only while the sun is up and only after you have see sunrise & UVA first (use MyCircadianApp to understand when this happens for you)
• Ideally you do this in the middle of the day when we have the strongest UV outside - which is between 10am - 2pm
• Bonus points - do outside or beside an open window so your eyes get a circadian cue (avoid looking at the UV lamp in this scenario)

3) Broad-spectrum photobiology

• UVB lamp - Sperti Vitamin D lamp (code carnivoreyogi10) + Red light device (code Sarahk for 45% off) - Sperti Vitamin D lamp contains 75% UVB & 25% UVA
• EMR-TEK Krypton - use code SARAHK for 45% off (UVA + UVB + red/IR). I like this because UVA/UVB arrive with red/IR, closer to solar balance, and red/IR supports skin/mitochondria and recovery.
• Red-light panel (code sarahk for 45% off) on non-UV days (does not make vitamin D): helps calm inflammation, support repair, and can make UV sessions easier to tolerate.

4) Why I don’t recommend tanning beds

• Most are heavy UVA, minimal (if any) UVB → tan without D, plus deeper dermal exposure that can be riskier. Essentially you get pigment (a tan) without the biology that comes with real sunlight.

UVA penetrates deeper into the dermis and without red/IR can drive:

• Greater oxidative stress
• DNA damage without the protective red/IR context sunlight provides
• Faster depletion of skin antioxidants (like glutathione)

Meanwhile, UVB is the wavelength that makes vitamin D and triggers the natural balancing photoproducts (lumisterol, tachysterol) that help regulate vitamin D metabolism and protect against over-activation.

Frequency I use my lamps:

• 3-4 sessions/week total in deep winter, alternating UV + Red/IR days with red/IR-only days.
• Sessions stay short. More is not better.

What to test (so your data are actually useful)

• 25-OH D (storage) and 1,25-(OH)₂ D (active) → pattern matters more than a single number (read my article on this)
• Magnesium (consider RBC Mg if available) → cofactor for D metabolism.
• PTH and Calcium (context for D status and safety).
• Optional: Ferritin, hs-CRP, thyroid panel- because inflammation and thyroid shift seasonal D dynamics.

Sweet spot: Many pooled analyses associate ~40–60 ng/mL 25-OH D with lowest all-cause risk- without chasing very high numbers that haven’t panned out in RCTs (and remember to always consider your 125D numbers).

Real risks with high-dose vitamin D pills (why I’m cautious)

• No fracture benefit from daily 2000 IU over ~5 years despite higher levels (VITAL primary outcomes were null for major endpoints). PMID: 30415629
• Annual 500,000 IU increased falls & fractures in older women. PMID: 20157135
• Monthly 60,000 IU increased falls in older adults. PMID: 26747333
• Calcium + D raised kidney stone incidence in WHI. PMID: 16481635

To be clear: I’m not anti-supplement; I’m anti-overriding physiology without solving upstream signals.

“But what if my vitamin D is very low going into winter?”

Here’s the order I’d follow personally (again - not medical advice):

1. Audit light + sleep: sunrise exposure when possible, dark nights (eye mask/blackout; kill bedroom light leaks), screen curfew.
2. Add gentle UVB (lamp) + red/IR support as above; start ultra-low and titrate by skin type.
3. Nutrition + cofactors: magnesium-rich foods/supp (check tolerance), vitamin A/K2 from food, adequate protein, omega-3s.
4. Address stress & inflammation: breath/cold/sauna as tolerated; move daily; manage blood sugar.
5. Re-test in 8–12 weeks.
6. If still very low or symptomatic, consider a modest, clinician-supervised - short term - D₃ + K2 & magnesium dose short-term while keeping the light/circadian protocol- then taper as physiology stabilizes.
7. Utilize a clinician who is familiar with circadian biology quantum biology & nutrition (here's a good directory)

Fast answers to FAQs:

• Sunshine is the source pathway; pills are a workaround. My stance is to restore the light-timing context, not chase a lab with megadoses.
• K2 doesn’t erase high-dose vitamin D risks. Magnesium is a legit cofactor - always check status, don’t assume.
• Red/IR can support repair, microcirculation, and tolerance. It doesn’t make vitamin D - think support, not substitute.

More FAQs:

“Why do I feel so good when I take vitamin D?”

Vitamin D acts similarly to a hormone, so when you take it, you may feel:

• a mood lift
• less inflammation
• more energy
• a short-term immune boost

Important: Feeling good doesn’t always mean it’s fixing the root signal - sometimes it’s just stimulating a pathway the body would normally regulate with light, circadian rhythm, and melatonin.

“What if my doctor says I need vitamin D pills?”

Advocate for context, and make your own decision based on all the information. I always tell my group members & clients that your "in person doctor" - has the benefit of a face to face conversation with you.

You can ask for:

• 25-OH D and 1,25-OH₂ D
• Magnesium (ideally RBC)
• Calcium + PTH

This gives a full picture instead of chasing one number, and can potentially give you & your doctor more information.

“What if I live in Canada / UK / Nordic regions?”

Having a winter plan is even more important:

• Morning outdoor light (even if cloudy)
• Darkness & rest at night
• Vitamin D + DHA-rich foods (cod, salmon, sardines, liver, eggs)
• (Highly Recommended) Red/IR support
• (Optional) UVB lamp (short, smart dosing) or a combo lamp like the Krypton

Northern latitude = intentional circadian strategy.

“Would you ever take vitamin D?”

Yes - in specific situations - strategically and short-term, not as my winter baseline.

Situations I’d personally consider it:

• Extremely low levels going into winter
• Short illness in someone not tolerating UVB
• After addressing light, sleep, and magnesium

And always supported with:

• Magnesium
• Vitamin K2
• Vitamin A from food
• Seasonal light, sleep, and stress support
• Red light therapy

And truthfully - I’m much more likely to use melatonin when sick than vitamin D - but more on that another day!

If you want my exact winter playbook

• Quantum Winter Blueprint (seasonal light/food/cold protocols - extended one more day)
• Leptin Resistance Quiz
• Leptin Master Plan (for practitioners/deep divers).
• MyCircadianApp Webinar (free): learn how to track sunrise/sunset, UV windows, Measure Lux, and build habits.

References & further reading

Article:  You've been warned about sunlight but not about supplements

• Manson et al. VITAL primary outcomes. N Engl J Med. 2019. PMID: 30415629
• Sanders et al. Annual high-dose D ↑ falls/fractures. JAMA. 2010. PMID: 20157135
• Bischoff-Ferrari et al. Monthly high-dose D ↑ falls. JAMA Intern Med. 2016. PMID: 26747333
• Jackson et al. WHI Ca+D ↑ kidney stones. N Engl J Med. 2006. PMID: 16481635
• Slominski et al. Melatonin, mitochondria & skin photobiology. Cell Mol Life Sci. 2020.
• Hamblin MR. Anti-inflammatory photobiomodulation. AIMS Biophys. 2017.
• Deng et al. Magnesium, vitamin D status & mortality (NHANES). BMC Med. 2013.
• Holick et al. Translocation of cutaneous vitamin D₃. Endocrinology. 1994.

New Article: This habit lowers your carb tolerance 25%

NEW EPISODE -Why Melatonin Isn’t Just for Sleep - Optimizing your winter hormones | Sarah Kleiner

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In Health🌞,

Sarah

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