Vitamin D and K with Sea-Iodine by Life Extension

If you’re looking for vitamin D and K with iodine in a single daily capsule, this fits adults whose Vitamin D, 25-Hydroxy is low or low‑normal, who want bone and calcium balance support without multiple bottles. It’s also relevant if your diet is low in iodine—common with strict vegan patterns, sea‑salt use without iodized salt, or minimal seafood/dairy—especially when your TSH (thyroid-stimulating hormone, the brain’s signal to the thyroid) runs high‑normal. If your level is frankly deficient, you may need a higher short‑term D3 plan first, then step down to this.

Vitamin D3 raises calcium absorption from the gut and helps lower parathyroid hormone (the signal that pulls calcium from bone). Vitamin K activates osteocalcin (a bone‑building protein) and matrix Gla protein (a calcium‑binding protein that helps keep calcium out of arteries), so calcium goes to the right places. Iodine enables the thyroid to make T4 and T3 (the hormones that set metabolic rate). The catch is that sudden high iodine can disrupt thyroid function in susceptible people, so fit matters more than dose bravado.

Take one capsule daily with food, ideally a meal containing some fat to improve absorption of vitamin D3 and vitamin K. Recheck Vitamin D, 25-Hydroxy after 8–12 weeks to gauge your personal response, and thyroid labs (TSH, Free T4) if you started with low iodine intake. The 5,000 IU D3 here is a common maintenance dose; those with established deficiency often need a higher or loading dose short‑term under clinician guidance, then transition down to a daily maintenance like this.

Avoid this if you use warfarin (vitamin K opposes its effect—dose changes require INR monitoring), have a history of high calcium, recurrent kidney stones, or granulomatous diseases like sarcoidosis that raise calcium. With thyroid disease, nodular goiter, Hashimoto’s, postpartum thyroiditis, or if you take amiodarone or lithium, extra iodine can cause swings in thyroid levels—use an iodine‑free vitamin D3 or work with your clinician. Pregnancy and breastfeeding: do not exceed clinician‑guided iodine intake.