Does drinking a lot of alcohol weaken your bones?

Three or more glasses of alcohol per day substantially increases the risk of a hip fracture: at three glasses per day the risk is 33% higher than in non-drinkers, and at four glasses per day it is as much as 59% higher. This comes from a meta-analysis of more than 240,000 participants. Chronic heavy drinking is therefore a recognised, independent risk factor for osteoporosis and bone loss.

How exactly this happens is partly understood. Alcohol suppresses the cells that build new bone; even brief social drinking causes a measurable marker of that cell activity to drop. With prolonged heavy use, additional problems arise: malnutrition, liver damage and hormonal disruptions, including lower vitamin D levels and disturbed calcium balance. As a result, calcium from food is absorbed less efficiently, while at the same time more calcium is lost through urine.

There is, however, a notable nuance. People who drink up to two glasses per day had, in the same meta-analysis, on average a slightly higher bone mineral density than people who do not drink at all. But that does not demonstrably translate into fewer fractures, and the association is likely partly explained by other lifestyle factors. It is therefore not a reason to start drinking for the sake of your bones.

Multiple osteoporosis-prevention guidelines recommend limiting alcohol, alongside adequate calcium and vitamin D, exercise and not smoking. If you already have low bone density or are at increased fracture risk for other reasons, discuss your alcohol use with your doctor.