Fat-soluble vitamins (A, D, E, K) accumulate in body fat and the liver — they do not need to be taken daily to maintain levels, but excess can accumulate and exceed safe intake levels, particularly for vitamins A and D. Water-soluble vitamins (B-complex, C) are not stored significantly and need consistent intake. Any excess of water-soluble vitamins is excreted normally, making toxicity rare at typical supplemental doses.
