How It Works

Vitamin D3 + K2: why both matter

D3 is activated by liver/kidney with magnesium as the cofactor — K2 does not activate D; it directs the calcium D helps absorb. K2 carboxylates osteocalcin (bone) and matrix-Gla protein (keeps calcium out of arteries). Food K2 is almost all MK-4 (short half-life, crosses to the fetus); supplemental MK-7 has a ~3-day half-life and sustains maternal status. The two are complementary.

MK-4 vs MK-7

MK-4 is made in and used by tissues quickly and reaches the fetus; MK-7 circulates for days and keeps blood levels steady. A protocol that supplies both covers the fetal and maternal sides. No vitamin K form has an established upper limit (caution only on warfarin).

The Ray Peat / PUFA lens

Peat argued polyunsaturated fats — especially seed-oil linoleic acid, but also excess fish oil — are prone to peroxidation and can suppress metabolism, so he favoured saturated fat and MUFA and kept PUFA low (often <4% of energy). The relevant fish PUFA is mostly omega-3 with established fetal-brain benefit, so the practical lever is fish frequency and freshness, not avoidance.

Calcium, B5 & B6

Calcium is highly bioavailable from dairy; pair with magnesium sources. Food calcium does not meaningfully block non-heme iron in whole-diet studies. Pantothenic acid (B5) and B6 occur across whole foods (meat, fish, dairy, grains, eggs), so a varied diet meets both; gentle cooking preserves them.

Units

One canonical unit per nutrient (mcg / mg / g / kcal, SI). Vitamin D is shown in mcg; a supplement's IU appears only inside its name label, never as a second computed unit.

Trimester guidance