Holland & Barrett Maximum Strength Vitamin D3 4000 I.U. Tablets offer a potent dose of vitamin D3, designed to support optimal health and wellness. Each tablet provides 4000 IU of vitamin D3, a high-strength formulation that plays a crucial role in maintaining normal bone and muscle function, as well as supporting the immune system. Vitamin D, often called the "sunshine vitamin" due to its production in the skin from sunlight exposure, is essential for maintaining healthy bones and muscle function. When UVB rays from the sun hit the skin, they trigger a chemical reaction that produces vitamin D3. However, obtaining sufficient vitamin D through sunlight alone can be challenging, especially for those with limited sun exposure. Therefore, taking Vitamin D supplements ensures you receive your daily dose of this vital nutrient. Vitamin D3 also plays a crucial role in supporting calcium and phosphate balance in the body, promoting normal bone health, muscle function, and immune system performance. Holland & Barrett Maximum Strength Vitamin D3 tablets are suitable for vegetarians contributing to overall bone health, muscle function, and immune support.