Suicide is currently the second leading cause of death among young people, after accidents.
LGB youth have a 3-4x higher attempted suicide rate than straight youth. Plus, their attempts are more serious, measured in terms of the percentage of attempts that require doctor actions as well as the surveyed reasoning (such as truly wanting to die vs. crying out for help).
LGB youth that have a highly rejecting family have a suicide rate that's about 8x as high as LGB youth that have an accepting family.
For transgender people, the rate is that they attempt suicide about 25x the rate of the national average. So that's about 40% of transgender people, attempting suicide at least once. The rates vary substantially depending on family acceptance, experience of employment discrimination, experience of physician discrimination, etc.
So, for LGBT youth, the rough math would mean that their death from suicide is higher than the rate from accidents, and most of it is attributed to family intolerance and society intolerance, since those that have relative acceptance in their lives have much lower rates.
Estimates vary widely for what percentage of the population is LGBT, with a common estimate being about 10 million people in the United States alone. That would mean hundreds of millions worldwide.
Sources: (
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I think the leading cause of death among millions of people when they're young due to oppression, is not something that can be compared to being unable to purchase a sandwich after 10pm.