The colour of the sky and ocean, blue is dreamy, spiritual and a colour of depth. On the contrary, it is also often associated with feelings of depression and sadness. Generally, in most Western countries, blue depicts masculinity, calm and authority. China links blue with strength and power, Japan sees blue as a colour of villainy. In the Middle East front doors are sometimes painted blue as the colour is thought to bring protection and ward off evil spirits.

Apart from its ability to calm the human mind, blue is also an appetite suppresant. Dying food blue or eating off a blue plate are tactics used by people hoping to lose weight, yet this may not be fully effective as blue doesn't stimulate a person's metabolism; it will often do the opposite. Blue food is rare in nature so this effect may be evolutionary -- we have no automatic appetite response to blue, and millions of years ago our ancestors considered blue, purple and black to be warning signs of poisonous food.

In recent times, food companies have started dying their products blue in hope to make them more appealing (Think of blue M&Ms, Heinz fries and those twisties which turn your tongue blue). These products probably sell so well because they're different, something new and would probably not sell so well if the novelty wasn't there. As blue is often considered pleasant and can suggest cleanliness, it is widely used in advertising. The fact that the colour is not as obtrusive as colours like red makes it an ideal choice for company logos.

Blue flowers, such as forget-me-nots or violets, are symbols of fidelity. Light blue candles portray truth, inspiration, wisdom, protection, inner peace and yet again, fidelity. Darker shades of blue connotate loyalty and expansion but should be used with caution.

During a dream blue generally represents the attitude to life, art, culture, religion and spirituality. Light blue links itself with hope and faith when encountered in a dream. Dark blue often shows a negative attitude on life, but this is not always the case.

In this day and age, blue is America's favourite colour. This may suggest a desire for calm or even represent widespread depression ;) but its most likely seen simply as a pleasant and soothing colour. Interestingly, sky blue is usually the preferred shade of women, whereas men take more of a liking to spectrum blue.

It is said that those who have a profound liking for blue are trusting and require trust, responsible, reliable and can be somewhat perfectionists. People who dislike blue may have an urge to break away from a repetitive lifestyle and can be linked with restlessness. Some may simply view it as depressing.

During the middle ages, a dull blue was the colour of servants and people of lower class. However, these days blue can suggest authority and power - in most countries police wear a blue uniform.

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