KLEAN-D 1000 IU by Klean Athlete

If your Vitamin D, 25-Hydroxy is in the lower end of normal and you want a maintenance dose, vitamin D3 1000 IU fits. It suits adults with little midday sun, darker skin, consistent sunscreen use, northern latitudes, or mostly indoor training. The dose is often enough for upkeep in spring and summer. Higher body weight, established deficiency, fat malabsorption, or winter at high latitudes usually require more under clinician guidance, then stepping down to this level.

Cholecalciferol (vitamin D3) is the form your skin makes from sunlight, and it raises blood levels more reliably than D2 (ergocalciferol). Your liver and kidneys convert it into the active hormone that increases calcium absorption from the gut and helps regulate bone turnover. Adequate D3 keeps parathyroid hormone (the signal that pulls calcium from bone) in check. It also supports muscle function and balance. Hopes that vitamin D prevents infections haven’t held up well in controlled trials, so don’t take it for that alone.

Take one tablet daily with a meal that contains some fat, which improves absorption. Morning or evening is fine—consistency matters more than timing. If you’re adjusting dose based on labs, recheck Vitamin D, 25-Hydroxy after 8 to 12 weeks. If you need more than 1,000 IU for repletion, a higher-strength D3 under clinician direction is more practical, then shift back to this for maintenance.

Skip unsupervised vitamin D3 if you have high blood calcium, recurrent calcium kidney stones, or granulomatous diseases like sarcoidosis, which can raise active vitamin D. Thiazide diuretics (blood pressure drugs that reduce calcium loss) increase the risk of high calcium with D3. Orlistat and cholestyramine reduce absorption, while long-term steroids and certain seizure medicines increase vitamin D needs. If you’re pregnant, use vitamin D but set the dose with your clinician and monitor Vitamin D, 25-Hydroxy.