Is a Vitamin D deficiency ruining your sleep?

Preview text: Plus, a quick reminder to save 10% sitewide - Ends Tonight

Sleep DoctorMonday, Apr 20, 2026 at 3:30 AM EasternKlaviyo
Sleep DoctorIs a Vitamin D deficiency ruining your sleep?
Subject
Is a Vitamin D deficiency ruining your sleep?
Preview text
Plus, a quick reminder to save 10% sitewide - Ends Tonight
From
newsletter@sleepdoctor.com
Sent
Mon Apr 20, 2026, 3:30 AM ET
Sent to
singularsleep.com, sleepdoctor.com
Size
84 KB
Images
11
Links
27, 10 of them buttons
Subject length
45 characters

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Sent in the 3 AM hour, which holds 20% of its emails; 23% arrive in the 9 AM hour. The subject is 45 characters; its average is 37.

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From
Sleep Doctor <[email protected]>
Subject
Is a Vitamin D deficiency ruining your sleep?
Date
Mon, 20 Apr 2026 07:30:18 +0000 (UTC)
Message-ID domain
geopod-ismtpd-5
Return-Path domain
email.sleepdoctor.com
DKIM signature
d=sleepdoctor.com s=kl2
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  1. from o1384.shared.klaviyomail.com [149.72.156.203] by our receiving server with ESMTPS
  2. by recvd-…-2gdjs with SMTP
  3. from (unnamed) by geopod-ismtpd-5 with HTTP

Other sending headers (names only): X-Kmail-Account, X-Kmail-Message, X-Kmail-Ops, X-Report-Abuse, X-SG-EID, X-SG-ID, X-Entity-ID

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