Your hands are filled with information about you. You might think that you can tell a person’s approximate age by looking at their hands, or perhaps what kind of work they might do. But, there are some things about your hands that may predict whether or not you are at an increased risk for certain conditions or diseases.

Here are 6 interesting examples:

1. Finger length

For women who have a ring finger that is longer than their index finger, there is an increased risk of developing osteoarthritis in the knees. There is also a higher incidence of athletic ability. For both genders, this trait may indicate a higher level of verbal aggression. For men, this trait may mean that they will have more children and better relationships with women, but there is also thought to be a higher risk of prostate cancer.

2. Trembling hands

Trembling or shaky hands may be an early sign of Parkinson’s disease. But, it can also be very benign, like a sign of having too much coffee. Shaky hands may also be related to medication side effects. If the tremor is in only one hand, it is generally more indicative of early Parkinson’s. Essential tremor is another possible diagnosis, but this is generally treatable.

3. Nail colour

A concentration of certain hormones or the presence of chronic anemia can affect the colour of a person’s nails. For those with half white and half brown nails, chronic kidney disease may be a problem. If you notice this half-and-half pattern, or a dark vertical stripe in your nail bed, see your doctor right away because this could be a sign of melanoma.

4. Poor grip strength

Those who have a weak grip may be at a higher risk for having a heart attack or stroke. Grip strength tends to be a better predictor of death than high blood pressure. Full body strength training can help, along with aerobic exercise.

5. Sweaty palms

If your palms are constantly clammy, you may either be nearing menopause or perhaps having thyroid problems. Overactive sweat glands are common in a condition known as hyperhidrosis, and people with this problem tend to sweat excessively from one or two parts of their body. Strong antiperspirants can help, but see your doctor to rule out serious problems.

6. Fingerprints

A British study found that people with a spiral or whorl pattern on their fingerprints were more likely to have high blood pressure than people with arched patterns in their fingerprints.

Most of these traits are only associations, and not a guarantee that you would have a certain condition. But, if you are concerned about any of the symptoms mentioned in this list, consult your doctor for proper diagnosis and treatment.