Weather not likely to make bones and joints ache. A study published in BMJ looked at whether an increase in humidity, rainfall, or barometric pressure can cause joint or back pain. Researchers looked at medical records of 11,673,392 Medicare outpatient visits. Matching the dates of the visits to local weather reports, they found that 2,095,761 of them occurred on rainy days. Using estimates they predicted how many of those visits were for a condition related to join or back pain, and how many of them occurred on rainy days. After controlling for age, sex, race and various chronic conditions, they found that more visits for bone and joint pain happened on dry days than wet ones. While the weather might not be causing joint pain, there might be some psychology involved; researchers say that when it’s raining and you have joint pain you might be more likely to attribute it to the weather than when it’s sunny and you have joint pain.