As humans we tend to react with a sense of pleasure to forms that possess certain symmetries or obey certain geometrical rules.
The Pentagram, a five pointed star, is a perfect example of the Golden ratio. The Golden ratio is the mathematically precise Universe expressed as 1.618...... Like all symbols, its original use was to represent counting systems prior to the development of the cardinal number system we know today.
The Pentagram is associated with the number five. Five represented the union of the first female number 2 with the first male number 3 and as such it was the number of love and marriage. The Pythagoreans apparently used the Pentagram as the symbol of their brotherhood and they called it "Health".
Today the Pentagram represents the five elements of health; Earth, Air, Water, Fire and Spirit. Pagan religions have adopted the Pentagram with one point at the top to represent their understanding of the Universe.
Unfortunately, the Pentagram inverted, with two points on top, has been adopted by Satanic practitioners and thus has generated fear about the Pentagram.
The Pentagram, with one point on top, invokes a loving energy and represents health, beauty and light. This is why I use it as a symbol for my health practice.
To read more about the Golden Ratio and The Pentagram
The Golden Ratio (2002). Mario Livio