​ ​ ​ ​ ​ ​ ​ Also - your chance to hang with me on zoom today! ​ ​ ​

If you’re over 40 and worried about losing muscle, read this

Hi Reader

Today I want to share a 2025 study that showed 2 groups of women who were postmenopausal, with low vitamin D, early muscle & bone loss.....and how light was the differentiator.

Keep reading for the details on how light did what the supplements alone couldn't

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Leptin Diet (if you just want the nutrition information from 21 Day Leptin Reset) - 40% off - click here ​

SUBSTACK ZOOM Q&A with me - today at 12:30 EST! All the details are in this article​

New here? Click here for my Free Product Guide & Click here for my favorite hair products​

Yesterday I published a new Substack article, and this one lit me up!

A 2025 study took a group of postmenopausal women, all vitamin D deficient, all with early bone loss, and split them in two. Both groups got the exact same vitamin D pill at the same dose. The only difference was that one group also got UVB light three times a week.

Six months later, the pill only group had barely moved. Still sitting at the bottom of the range, with essentially no change in their muscle strength. The group that added light nearly doubled their vitamin D, got measurably stronger, and built more bone at the hip and spine.

Same vitamin D dose & the UVB light did the rest! And that’s before we even get into everything sunlight does that has nothing to do with vitamin D at all, the nitric oxide, the mitochondrial piece, the mood chemistry. I break all of it down, with the actual numbers and the research, right here: [Substack article]​

If you’d rather watch than read, I turned the whole thing into a new YouTube video. Same science, a little more room to explain it, and I walk through what it actually means for you and your routine: [YouTube video]​

Here are the timestamps:

​
​00:00 Supplements Hidden Costs

​00:47 Study Setup And Context

​02:15 Who The Study Tested

​04:16 Pills Versus UVB Results

​05:11 Strength And Bone Gains

​06:30 Solar Metabolome Explained

​07:39 Sunlight Beyond Vitamin D

​07:59 Nitric Oxide And Blood Pressure

​09:06 Red Light Mitochondria Boost

​10:10 Mood Appetite Sun Chemistry

​10:37 Study Takeaways And Next Steps 1​

​1:31 Final Resources And Wrap Up

Lastly - My subscriber Zoom is today, Wednesday July 8th, at 12:30 PM Eastern Standard Time. This is where I get to go deeper and answer your questions live, and it’s just for you all. All the details on how to join are inside that Substack article (click here)!

Hope this article was helpful - please feel free to share with a friend or family member!

See you soon,

Sarah

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In Health🌞,

Sarah

PS - This newsletter is not medical advice nor a substitute for 1:1 care with a trusted practitioner!