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Why are water-soluble vitamins less likely than fat-soluble vitamins to build up to toxic levels in the body?

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rickets, a nutritional disease — nutritional disease Children with rickets. The disease, which most commonly strikes children, causes bone deformities such as bowlegs. Rickets is caused by a lack of vitamin D or calcium.

Water-soluble vitamins are less likely than fat-soluble vitamins to reach toxic levels in the body primarily because they are not stored in significant amounts in body tissues. With the exception of vitamin B12, which is stored differently, water-soluble vitamins are readily excreted in the urine when consumed in excess.123

In contrast, fat-soluble vitamins—vitamins A, D, E, and K—are stored in the liver and fatty tissue. Because the body retains these vitamins over longer periods, they have a much higher potential for accumulation and toxicity if consumed in very large doses. While water-soluble vitamins are generally considered less toxic, it is important to note that they can still cause adverse effects if taken in excessive amounts through supplements or fortified foods.4123