We all have certain fixed ideas about what's good for us and what isn't. These ideas are often fuelled by folklore, incomplete knowledge from various publications or the Internet, incorrect interpretation of this knowledge and, of course, misinformation and exaggeration by television commercials. To set the record straight -- at least as far as skincare goes -- here are a few common myths and the truth behind them.

Myth: "My sunscreen will prevent tanning"

Fact: No sunscreen prevents tanning. It only decreases sun induced skin damage such as sunburn and delays photo-aging. Only a physical block like dark cloth or an umbrella can protect you.

Myth: "The longer I keep hair oil on, the better it is for my hair"

Fact: You actually need hair oil only for half an hour to an hour. It merely smoothens frizzled hair cuticles and is not absorbed into the hair shaft or scalp. In fact, keeping oil in your hair for a longer period or overnight traps dirt, causes build up of residue and leads to blackheads and acne on the forehead.

Myth: "My skin is normal / oily, so I don't need moisturizer"

Fact: Moisturiser does not add oil to the skin -- it hydrates, ie makes water molecules move into the cells of your skin, making it look smoother and softer. In fact, even oily skin needs frequent cleansing to remove excess oil and sebaceous secretion, followed by an application of moisturiser.

Myth: "Applying cream at night is bad as it prevents my skin from breathing"

Fact: Most of the skin's self-repairing activity occurs at night and nourishment given at this time can only maximise benefits. Most night creams are non oil-based, non-greasy formulations that do not block pores and supply essential rejuvenating substances.

Myth: "Home / natural remedies are 100 per cent safe"

Fact: If you have sensitive skin, even homemade packs and natural cleansers (eg turmeric, multani mitti, besan) can cause allergies or irritant reactions. Not all skin types are alike, so what works for most people may backfire for you. Always perform a test patch of a home remedy before applying it all over your face.

Myth: "Shampooing frequently increases hair fall"

Fact: Shampooing only dislodges hair that is already dead (Telogen Hair), which otherwise would have shed off on its own without your realising it. Live hair, in its growing stage (Anagen Hair), cannot be pulled out by shampooing. It is normal to lose 100 strands of hair per day.

Myth: "Fairness cream will transform me from a black beauty to a swan"

Fact: No one is going to offer you a movie role after three months of applying any cream in the world. Your skin colour is largely genetic and fairness products can make a difference of a few shades. Be realistic in your expectations. Yes, with intensive skin improvement, under a dermatologist's supervision, your skin can definitely become more even toned, less patchy, healthier and up to 30 to 35 per cent lighter -- but no one can make you Snow White -- that's a fairy tale!

Myth: "Stress causes greying of hair"

Fact: Stress only causes falling of hair. This affects only black hair, which is how the grey begins to show more as the black hair decreases. Greying, especially premature greying, is determined more by your genes.