Which is a symptom of vitamin deficiency?

A lack of coordination can often be a symptom of certain vitamin deficiencies, particularly those involving vitamins that play crucial roles in nervous system function and muscle coordination, such as vitamin B12 or vitamin E. When the body does not receive enough of these nutrients, various neurological symptoms can arise, including difficulties with coordination and balance.

In contrast, the other options suggest positive effects that are not typically associated with vitamin deficiencies. Increased energy levels, improved digestion, and enhanced cognitive function usually indicate that the body is receiving adequate nutrition rather than a deficiency. Thus, the presence of a lack of coordination aligns with the physiological impacts seen when certain vitamins are deficient in the diet, highlighting the importance of vitamins in maintaining overall health and bodily functions.