Know what you're putting in your body.

158 herbs, nutrients, and compounds. What the science says, what tradition knew, and what to watch for. Founding members keep this running.

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IMMUNE-BOOST

Vitamin D

also known as Vitamin D2, Ergocalciferol, Vitamin D3, Cholecalciferol…

Supports calcium and phosphorus use, bones, teeth, growth, muscle strength, heartbeat regulation, immunity, thyroid function, blood clotting, osteoporosis prevention, and breast/colon health.

Recommended daily intake

Adults 19 70 · 600 IU (15 mcg)
Adults 71 Plus · 800 IU (20 mcg)
Pregnancy Lactation · 600 IU (15 mcg)

Upper intake limit

4,000 IU (100 mcg) per day for most adults

Signs of deficiency

Bone pain, muscle weakness
Increased fracture risk
Rickets in children — bowed legs, soft skull
Osteomalacia in adults — bone tenderness, weakness

Supports calcium absorption
Supports phosphorus absorption
Supports bone health
Supports tooth development
Supports growth
Helps protect against muscle weakness
Supports heartbeat regulation
Supports immune function

Enhances

Calcium Vitamin D upregulates intestinal calcium transporters (TRPV6, calbindin), directly driving active calcium absorption.

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