What could significantly slow down the nail growth rate?

Insufficient nutritional intake is a crucial factor that can significantly slow down nail growth rate. Nails are composed of a protein called keratin, and the body requires an adequate supply of vitamins, minerals, and nutrients to produce keratin effectively. A diet lacking in essential nutrients, such as biotin, proteins, zinc, and iron, can lead to slower growth as the body prioritizes its resources for more vital functions.

Inadequate nutrition can also affect overall health, which subsequently impacts the health of hair and nails. When the body doesn't receive the nourishment it needs, it may divert energy away from non-essential processes like nail growth, leading to thinner, weaker nails that grow at a reduced pace.

Other factors like exposure to water and regular nail clipping may have some influence on nail health but do not inherently cause a significant decrease in the rate of nail growth. Excessive water exposure can actually promote nail health when managed properly, and regular nail clipping is a maintenance practice that typically has no negative impact on the rate at which nails grow.