Researchers followed 722 Norwegian teenagers from age 16 to 27 to see if smoking or using snuff (a type of tobacco) affected their bone strength. They measured bone density three times over 12 years using special X-ray scans. The surprising finding: smoking and snuff use didn’t seem to weaken bones during these important growing years. However, very few teenagers in the study smoked regularly, so scientists can’t be completely sure this would apply to heavier smokers. The study suggests that moderate tobacco use may not harm bone development as much as previously thought, but this doesn’t mean tobacco is safe.

The Quick Take

  • What they studied: Whether smoking cigarettes or using snuff tobacco affects how strong and dense bones become as teenagers grow into adults
  • Who participated: 722 Norwegian teenagers (385 girls and 337 boys) starting at age 16, followed for 11 years until age 27. The study included people from the general population, not just smokers
  • Key finding: Teenagers who smoked or used snuff did not have noticeably weaker bones compared to those who never used tobacco. The only exception was 18-year-old girls who sometimes smoked had slightly lower hip bone density than those who never smoked
  • What it means for you: If you’re a teenager or young adult, occasional smoking may not immediately damage your bones as much as doctors previously thought. However, this doesn’t mean tobacco is safe—it still harms your lungs, heart, and overall health in many other ways. The study looked at light to moderate use, not heavy smoking

The Research Details

This was a long-term follow-up study that tracked the same group of people over time. Researchers measured bone density using a special X-ray machine called DXA (dual-energy X-ray absorptiometry) at three different time points: when participants were 16 years old, 18 years old, and 27 years old. They also collected blood samples to check vitamin D levels and asked participants detailed questions about their tobacco use, exercise, alcohol consumption, and other health factors.

Participants reported whether they never used tobacco, sometimes used it, or used it daily. The researchers then compared how bone density changed over time between these different groups. They focused on bones in the hip area (total hip and femoral neck) and the entire body, since these are common places where bones become weak later in life.

Following the same people over many years is important because it shows how tobacco use affects bone development during the critical teenage and young adult years when bones are still growing and getting stronger. This approach is better than just taking a snapshot at one point in time. By measuring bones at three different ages, researchers could see whether tobacco use slowed down bone growth or caused bones to weaken over time

This study has several strengths: it followed a large group of people over 12 years, used accurate bone-measuring technology, and included detailed information about many factors that affect bone health. However, there are some limitations to consider: very few participants smoked daily (only 2.6% of girls and 3.9% of boys), so the study mainly looked at light to moderate smoking. The study also relied on people reporting their own tobacco use, which might not always be completely accurate. Additionally, the study only included Norwegian teenagers, so results might differ in other populations

What the Results Show

Overall, bone density increased normally in both boys and girls as they aged from 16 to 27 years, which is what scientists expect during these growing years. Teenagers who smoked or used snuff had similar bone density increases compared to those who never used tobacco. The researchers found no clear pattern showing that tobacco use slowed down bone growth or made bones weaker.

There was one small exception: at age 18, girls who sometimes smoked had slightly lower hip bone density compared to girls who never smoked. However, this difference was small and didn’t continue as they got older. By age 27, there were no differences in bone density between smokers and non-smokers.

The study measured three specific areas: the total hip (the entire hip bone), the femoral neck (the narrow part of the thigh bone near the hip), and the total body. In all three areas, tobacco use did not significantly affect bone density changes over time.

The researchers also looked at whether the amount of tobacco use mattered. They compared people who never used tobacco, sometimes used it, and used it daily. Even when comparing daily users to never-users, there were no significant differences in bone density. This suggests that even regular tobacco use during adolescence and young adulthood may not strongly impact bone development, at least in the short to medium term

Previous research has suggested that smoking might weaken bones, especially in older adults. This study suggests that the relationship between tobacco and bones may be more complicated than previously thought, particularly in younger people. The findings don’t contradict earlier research but suggest that the harmful effects of smoking on bones may develop later in life or may require heavier, longer-term smoking. It’s also possible that young people’s bones are more resilient and can recover from tobacco’s effects better than older adults’ bones

The biggest limitation is that very few people in the study smoked regularly. Only about 3-4% smoked daily, so the study mainly looked at light to moderate smoking. Results might be different for heavy smokers. Second, people reported their own tobacco use, which could be inaccurate. Third, the study only included Norwegian teenagers, who may be different from teenagers in other countries in terms of genetics, diet, or lifestyle. Finally, the study only followed people until age 27, so it’s unknown whether tobacco use causes bone problems later in life

The Bottom Line

Based on this study alone, there is moderate evidence that light to moderate tobacco use during adolescence and young adulthood may not immediately weaken bones. However, this should NOT be interpreted as tobacco being safe. Tobacco harms your health in many other important ways (lungs, heart, cancer risk) that are well-proven. If you don’t smoke, don’t start. If you do smoke, quitting is still strongly recommended for your overall health

This research is most relevant to teenagers and young adults who smoke occasionally or moderately, and their parents or doctors who are concerned about bone health specifically. It’s also important for healthcare providers counseling young people about tobacco use. However, the findings should not change anyone’s decision about smoking, since tobacco causes many other serious health problems. People with family histories of weak bones or osteoporosis should still avoid smoking, as they may be at higher risk for bone problems

Bone density changes happen gradually over years and decades. This study measured changes over 11 years and found that tobacco use didn’t significantly slow bone growth during this time. If bone damage from smoking does occur, it may take many more years to become noticeable. The best approach is to maintain healthy bones through exercise, adequate calcium and vitamin D, and avoiding tobacco—regardless of what this one study shows

Want to Apply This Research?

  • Track tobacco use frequency (never, sometimes, daily) alongside bone-health behaviors like calcium intake, vitamin D levels, and weight-bearing exercise. Record this weekly to see patterns over time
  • If you’re a young person who smokes occasionally, use the app to set a goal to reduce frequency or quit entirely. Track alternative stress-relief activities (exercise, meditation) to replace smoking habits. Even though this study suggests bones may not be immediately affected, quitting improves lung and heart health
  • For users concerned about bone health, monitor calcium intake (aim for 1000-1200mg daily), vitamin D status (through blood tests), and regular weight-bearing exercise (30 minutes most days). Track these factors monthly and review trends quarterly. If you smoke, document quit attempts and progress

This research suggests that light to moderate tobacco use may not immediately weaken bones in teenagers and young adults, but this finding should NOT be interpreted as tobacco being safe or healthy. Tobacco use causes serious harm to your lungs, heart, and overall health through well-established mechanisms. This study only followed people until age 27 and only examined light to moderate smoking—effects on heavy smokers or over longer lifespans are unknown. Always consult with a healthcare provider about your personal tobacco use and bone health, especially if you have risk factors for weak bones. This information is for educational purposes only and should not replace medical advice from qualified healthcare professionals.