Do carbonated drinks damage your bones?
Regularly drinking large amounts of sugary carbonated drinks is associated with lower bone density, especially in women and during puberty. Moderate consumption appears less harmful, but it is preferable to replace soft drinks with beverages that support bone development.
Cola and other sugary carbonated drinks are associated with lower bone density, as shown by research involving more than 124,000 adults. The association is strongest in women under 50, where the effect size grows to more than double the average effect. This is an association, not a proven cause-and-effect relationship, but the pattern is consistent enough to take seriously.
During puberty, the effect may be most relevant. A study of adolescents aged 12 and 15 found an inverse association in girls specifically, not in boys. Part of this effect may be explained by soft drinks displacing milk or other beverages that contribute to bone development. That mechanism -- the crowding out of nutrients -- may itself be harmful, independently of the soft drink consumption.
On the possible biological mechanism: cola contains phosphoric acid, and an excessively high phosphorus intake from processed foods can disrupt the hormonal balance involving phosphorus, calcium and vitamin D. This disruption promotes bone breakdown and inhibits bone formation. The mechanism has been described in two reviews. Whether reducing phosphorus intake actually prevents fractures has not yet been well studied.
Moderate consumption in older women appears less concerning. Research in women aged 44 to 98 found no demonstrable association between moderate consumption of carbonated drinks and bone density, after accounting for age, calcium intake, physical activity, smoking, alcohol use and hormone use. The harm therefore does not appear to come from the bubbles alone, but from what is in the drink, how much you consume, and what else you put against it in the rest of your day.
This answer rests on a large analysis of 26 studies with more than 124,000 participants, supplemented by individual studies in adolescents and older women, and two narrative reviews on phosphate and bone metabolism. The association between sugary carbonated drinks and lower bone density is consistent, but cause and effect cannot be established with certainty: people who drink large amounts of soft drinks often eat and live differently from those who do not. The phosphoric acid mechanism is biologically plausible, but direct evidence that reducing phosphorus intake also prevents fractures is still lacking.
Does drinking a lot of alcohol weaken your bones?
Chronic heavy drinking demonstrably weakens your bones and substantially raises the risk of a hip fracture; for your bones there is no safe level above two drinks per day.
Is eating plant-based bad for your bones?
Eating strictly vegan is associated with lower bone density, but if you adequately supplement calcium and vitamin D, the elevated fracture risk largely disappears. As a vegan, also pay attention to vitamin B12, and discuss any supplement use with your GP or dietitian.
Can statins (cholesterol-lowering medications) affect your bones?
Statins show positive effects on bone in laboratory and animal research, but randomised trials in humans do not confirm this. There is therefore no need to reconsider your cholesterol medication for the sake of your bones, but do not expect any bone protection from it either.
Does taking cortisone long-term weaken your bones?
Long-term cortisone use demonstrably weakens your bones; if you use it long-term, it is wise to discuss with your doctor whether you are a candidate for bisphosphonates as a protective measure.
Can having too little body fat damage your bones?
Too little fat can damage your bones, but muscle mass and the location of fat matter at least as much. If you have concerns about bone health in combination with low body fat, discuss this with your general practitioner or sports medicine physician.
What happens to your bones when you lie in bed for a long time?
Prolonged bed rest demonstrably leads to substantial bone loss, particularly in the hip, spine and heel bone. Recovery takes much longer than the period of bed rest itself, so resuming movement as soon as possible is the best thing you can do.