From finger length to grip strength, our hands can indicate risk factors for a number of surprising conditions.
Finger length reveals: Arthritis risk
Women with ring fingers that are longer than their index fingers, typically a male trait, are twice as likely to have osteoarthritis in the knees, according to an Arthritis & Rheumatism study.
Low estrogen levels may be a factor. The same feature has been linked to higher athletic ability and verbal aggression in both genders.
In men, a significantly longer ring finger (indicating an in-utero testosterone surge during the second trimester) is associated with having more children and better relationships with women, but a higher risk of prostate cancer.
Shaky hands reveal: Parkinson’s disease
Trembling hands could be the result of something as simple as too much caffeine or a side effect of certain medications like asthma drugs and antidepressants. But it’s a good idea to see your doctor if the issue recurs.
A tremor in just one hand can be a first symptom of Parkinson’s disease, or it can indicate essential tremor, a disorder that causes uncontrollable shaking (treatable with therapy or medication).
Nail color reveals: Kidney disease
When Indian researchers studied 100 patients with chronic kidney disease, they found that 36 percent had half-and-half nails (the bottom of a nail is white and the top is brown).
The nail condition may be caused by an increased concentration of certain hormones and chronic anemia, both traits of chronic kidney disease.
See your doctor right away if you notice half-and-half nails or a dark, vertical stripe beneath the nail bed. This can be hidden melanoma, a skin cancer.
Grip strength reveals: Heart health
A weak grip predicts a higher risk of heart attack or stroke and lower chances of survival, according to a new Lancet study of nearly 140,000 adults in 17 countries. Grip strength was a better predictor of death than was blood pressure.
Researchers say grip strength is a marker of overall muscle strength and fitness, and they recommend whole-body strength training and aerobic exercise to reduce heart disease risk.
Sweaty palms reveal: Hyperhidrosis
Overly clammy hands may be a symptom of menopause or thyroid conditions, as well as hyperhidrosis, in which overactive sweat glands cause far more perspiration than necessary.
Most people with the condition sweat from only one or two parts of the body, such as the armpits, palms, or feet. A doctor may prescribe a strong antiperspirant to decrease sweat production.
Fingerprints reveal: High blood pressure
When British researchers studied 139 fingerprints, they found that people with a whorl (spiral) pattern on one or more fingers were more likely to have high blood pressure than people with arches or loops.
The more fingers with whorls a participant had, the higher his or her blood pressure was. Fingertip whorls are markers of fetal development problems during certain stages of pregnancy, which may affect blood pressure later in life.