Word that means "to constantly being worried by one's appearance?"

The closest thing I could think of was self-conscious. According to Wikipedia:

Self-consciousness is an acute sense of self-awareness. It is a preoccupation with oneself, as opposed to the philosophical state of self-awareness, which is the awareness that one exists as an individual being.

It doesn't seem to refer to one's physical appearance, though.

Is there a word to convey that?

Solution 1:

Vain:

excessively proud of or concerned about one's own appearance, qualities, achievements, etc.; conceited:

Someone who always wants to make sure they look good / make sure they don't look bad, is vain. However, it conveys want rather than worry, so may not be a perfect fit.

Solution 2:

Fop:

a man who is devoted to or vain about his appearance or dress

Someone who is obsessed over their appearance. This would be someone who cares very much about his appearance. A synonym would be:

Dandy:

plural: dandies

a man who gives exaggerated attention to personal appearance

Same as fop, but more commonly used.

Solution 3:

I would describe that person as being narcissistic

Narcissist:

noun

1. a person who is overly self-involved, and often vain and selfish.
2. Psychoanalysis. a person who suffers from narcissism, deriving erotic gratification from admiration of his or her own physical or mental attributes.

I emphasized "physical" per your question.

Upon searching for "narcissistic" via Google, it comes up with:

adjective

having an excessive or erotic interest in oneself and one's physical appearance.

but I do not know Google's source for the definition.

Solution 4:

There is a psychological term that might work for you, if the worry is truly constant. Body dysmorphic disorder (sometimes body dysmorphia)

is a mental disorder in which you can't stop thinking about one or more perceived defects or flaws in your appearance . . . . When you have body dysmorphic disorder, you intensely obsess over your appearance and body image, repeatedly checking the mirror, grooming or seeking reassurance, sometimes for many hours each day.

(From the Mayo Clinic's Patient Care & Health Information)

Note that the perceived flaw can be anything, including obvious things like weight but also things like obsessing about a particular body part, and that it is usually unnoticeable to other people. A commonly related disorder is anorexia, whose sufferers may believe that they look fat even as they starve to death. (See, e.g., this article.)

This is distinct from traditional notions of vanity, as the obsession with appearance generally does not arise from pleasure or pride in that appearance. Narcissus, for example, fell in love with his own reflection (Wikipedia). A sufferer of body dysmorphia, on the other hand, may also spend an inordinate amount of time looking at his or her reflection, but would be distressed by what he or she saw there.