Medical astrology is an ancient medical system that associates various parts of the body, diseases and drugs as under the influence of the Sun, Moon and planets, along with the twelve astrological signs. Hippocrates, the Greek physician who is regarded as the father of medicine, insisted his students study astrology, saying, "He who does not understand astrology is not a doctor but a fool". Each of the astrological signs (along with the Sun, Moon, and planets) are associated with different parts of the human body. Also, many plants are referred to in old treatises on herbs as being "under the influence of" some planet. This was used as a codification of tassociations of the signs with the parts of the body are as follows:

• Aries - head, face, brain, eyes
• Taurus - throat, neck, thyroid gland, vocal tract
• Gemini - arms, lungs, shoulders, hands, nervous system
• Cancer - chest, breasts, stomach, alimentary canal
• Leo - heart, chest, spine, spinal column, upper back
• Virgo - digestive system, intestines, spleen, nervous system
• Libra - kidneys, skin, lumbar region, buttocks
• Scorpio - reproductive system, sexual organs, bowels, excretory system
• Sagittarius - hips, thighs, liver, sciatic nerve
• Capricorn - knees, joints, skeletal system
• Aquarius - ankles, calves, circulatory system
• Pisces - feet, toes, lymphatic system, adipose tissue

It has been noted that the 12 signs cover from head (Aries) to toe (Pisces), because Aries is the first sign of the zodiac while Pisces is the last. When the Sun passes from Pisces to Aries on or around March 21st, the Vernal equinox occurs, and thus the beginning of a new tropical year. Many astrologers celebrate their New Year when the Sun transits over this point, which is also known as the First Point of Aries.

According to Marcus Manilius (1st century AD) in his epic poem (8000 verses) Astronomica, the signs of the Zodiac preside over the parts of the body as follows:

• Aries -- the head
• Taurus -- the neck and throat
• Gemini -- the lungs, arms, and shoulders
• Cancer -- the chest, breasts and stomach
• Leo -- the heart and upper back
• Virgo -- the abdomen and digestive system
• Libra -- the kidneys and lumbar region
• Scorpio -- the genitals
• Sagittarius -- the hips and thighs
• Capricorn -- the knees and bones
• Aquarius -- the calves, shins and ankles
• Pisces -- the feet

For Manilius' associations between body parts and the planets, see Solar system in astrology.

The planets are also associated with certain portions and functions within the body:

• Sun - heart, spine, and general vitality
• Moon - stomach, digestive system, female organs, lymphatic system
• Mercury - brain, central nervous system, thyroid gland, five senses, hands
• Venus - throat, kidneys, thymus gland, sense of touch, ovaries
• Mars - muscles, head, adrenal glands, senses of smell and taste
• Jupiter - liver, thighs, feet, growth, pituitary gland
• Saturn - skin, hair, teeth, bones, the body's defenses, spleen
• Uranus - parathyroid gland, neural activity, aura
• Neptune - pineal gland, psychic healing
• Pluto - pancreas, metabolism, elimination

After examining an individual's natal chart, a medical astrologer would give advice to the client about the areas of the body they are most likely to experience trouble with -- for instance, an individual with the Sun, Moon, Ascendant, or many planets in the sign of Aries is presumed to have more headaches than other people because of the association of Aries with the head. A person with Taurus strong in the natal chart is predicted to have many sore throats and problems with the voice because of the Taurean association with that particular part of the body.

Astrology by type | Astrology | Astrological factors