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Vitamin D3 + K2 (via iHerb)
☀️ Vitamin D3 + K2
Vitamin D3 + K2
The gap so many people quietly have.
What it is
Vitamin D is the 'sunshine' nutrient your skin makes from sunlight, supporting bones, mood, and immune function. K2 is its common companion — the two are often paired because they work together in how the body handles calcium.
Why the experts include it
Vitamin D is one of the few nutrients experts routinely suggest testing for, because so many people run low — especially in winter, at higher latitudes, or with more time spent indoors. The clean, simple D3 + K2 combo is a common foundational pick.
Why it matters on a GLP-1 journey
Eating much less can quietly shrink your intake of fat-soluble vitamins like D. Since it's hard for many people to get enough from food alone, a clean daily D3 (often paired with K2) is an easy gap-filler on a lighter-appetite phase.
Vitamin D to fill a common gap
Fat-soluble vitamins like D are easy to fall short on when you eat less. A clean daily D3 (often paired with K2) is a simple way to cover a gap many people have anyway.
General amounts (not a prescription)
Daily amounts on labels commonly range from about 1,000–2,000 IU; some people need more based on testing — follow the label and your clinician's guidance.
What to look for in a clean product
- D3 (cholecalciferol) rather than D2
- Paired with K2 (MK-7) in many quality formulas
- Third-party tested, clean softgel or liquid
- A dose that matches your needs — testing helps
Our vetted picks
Three clean, third-party-tested options — Good, Better, Best.
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Common questions
Do I need more vitamin D when I'm eating less on a GLP-1?
Vitamin D is fat-soluble, and on smaller meals you may be having fewer D-rich foods like oily fish, eggs, and fortified dairy. Shortfalls are already common in the general population. A simple blood test (25-OH vitamin D) tells you where you actually stand. Most general-wellness ranges land around 1,000–2,000 IU of D3 a day, but your clinician sets the right amount for you.
Why is K2 paired with D3?
D3 helps your body absorb calcium; K2 (the MK-7 form) helps direct that calcium toward bone. The pairing is common for that reason. When overall nutrient intake is lower because meals are smaller, a combined D3 + K2 product covers both in one capsule. It isn't mandatory, but it's a sensible, low-effort design for a clean daily base.
How much D3 and K2 should I take on a GLP-1?
A common maintenance range is about 1,000–2,000 IU of D3 with 90–200 mcg of K2 (MK-7) a day for general adult wellness. Higher D3 amounts exist but should follow a blood result, not guesswork. These are general nutrition benchmarks — a clinician or dietitian should set your personal target, especially if you're managing bone health.
What's the best form of vitamin D to take?
D3 (cholecalciferol) raises blood levels more efficiently than D2, and for K2 the MK-7 form lasts longer so once-daily works well. Both are fat-soluble, so take them with a meal that has a little fat — even a small amount helps absorption. On a lighter appetite, pairing them with a fish-oil capsule at the same time is an easy habit.
D3 + K2 or a multivitamin — do I need both?
A multivitamin often includes some D3, but usually at a modest amount, and may skip K2 entirely. Check the label math before stacking. If your multi already covers the D3 you need, a separate pill is redundant; if it falls short, a dedicated D3 + K2 fills the gap. Audit what you already take before adding anything new.
General wellness and nutrition information, not medical advice. We help with nutrition, not medication — talk to your clinician or pharmacist about your medication and routine.