A kintsugi-repaired vessel can still be used for food if the right conditions are met. But you cannot judge that from the gold-colored repair alone. What matters is what materials were used in the repair.
Traditional kintsugi repairs cracks and chips with urushi lacquer and finishes them with metal powder such as gold. Today, there are also simplified forms of kintsugi that use materials such as epoxy resin. That does not mean simplified kintsugi is automatically unsafe. Some materials are suitable for use on tableware, while others are not.
With traditional kintsugi, it is important that the urushi lacquer has fully cured. With simplified kintsugi, you need to know whether the materials used are suitable for tableware. If you repaired the piece yourself, or the person who repaired it explained how it can be used, that is easier to judge. With a secondhand piece whose repair materials are unknown, more caution is needed.
It is also important to remember that “safe to use for food” does not necessarily mean “use it exactly like the original vessel.” Depending on the metal powder and other repair materials, a repaired vessel may need to be kept out of the microwave or dishwasher.
Kintsugi is widely known as a traditional Japanese repair technique. But in everyday life, it is actually rare to come across a vessel that has been repaired this way. It is not something that most Japanese households simply have several of sitting in the cupboard.
Even so, there is usually a reason someone goes to the trouble of repairing a vessel with kintsugi. It does not have to be expensive. It might be a bowl used for many years or something received from someone important. Sometimes a vessel is repaired and kept in use not because it is valuable in money, but because it matters to the person who owns it.
