“The years from childhood until age 30 are prime time for building bone mass. “If an adolescent is smoking, they will not develop maximum bone mass. They will end up with a smaller skeleton and less bone mass, compared to a nonsmoker,” says Primal Kaur, MD, an osteoporosis specialist at Temple University Health System in Philadelphia.
Smoking weakens bones in several ways, including:
- Studies have shown that smoking reduces the blood supply to bones, just as it does to many other body tissues.
- The nicotine in cigarettes slows the production of bone-forming cells (osteoblasts) so that they make less bone.
- Smoking decreases the absorption of calcium from the diet. Calcium is necessary for bone mineralization, and with less bone mineral, smokers develop fragile bones (osteoporosis).
- Smoking seems to break down estrogen in the body more quickly. Estrogen is important to build and maintain a strong skeleton in women and men.
Dr. George Cierny III and his colleagues studied the role of tobacco smoking in bone healing. The study, which was conducted at Emory University in Atlanta, revealed that bone formation during bone transports was much slower in patients who smoked than in patients who did not smoke
The researchers studied 29 patients who were being treated for a fractured tibia (shin bone) and who developed infection of the bone (osteomyelitis). Patients answered a questionnaire regarding their smoking history. Also, each patient had blood and urine tests to verify his or her exposure to nicotine and cotinine, which are contained in tobacco. The patients were divided into groups of nonsmokers, former smokers, and current smokers.
The physicians took x-rays of the patients’ legs at different times so they could assess the rate of healing. They found that the nonsmoking patients formed new bone much faster than the patients who continued to smoke during the study. The average length of time for a nonsmoker to form 1 cm of new bone was 69.6 days, compared with 89.4 days for the smokers. Based on this rate, if a patient needed to form 5 cm (2 inches) of new bone, it would take 10 months for a nonsmoker and 15 months for a smoker.
Why are bones affected by smoking?
Bones are nourished by blood much like the other organs and tissues in your body. Nutrients, minerals, and oxygen are all supplied to the bones via the blood stream. Smoking elevates the levels of nicotine in your blood and this causes the blood vessels to constrict. Nicotine constricts blood vessels approximately 25% of their normal diameter. Because of the constriction of the vessels, decreased levels of nutrients are supplied to the bones. It is thought that this is the reason for the effect on bone healing.
There’s no question that kicking the habit is the way to go. If you or a loved one smoke, no one needs to tell you that — you already know, and chances are, you’ve tried to quit. And of course the general rule- prevention is better than cure, applies directly to smoking and bone-loss. The effects that smoking has on your body cannot be reversed, break the habit.