Alcohol consumption.

From: https://www.nytimes.com/2018/08/28/upshot/alcohol-health-risks-study-worry.html

For each set of 100,000 people who have one drink a day per year, 918 can expect to experience one of the 23 alcohol-related problems in any year. Of those who drink nothing, 914 can expect to experience a problem. 

This means that 99,082 are unaffected, and 914 will have an issue no matter what. Only 4 in 100,000 people who consume a drink a day may have a problem caused by the drinking, according to this study.

At two drinks per day, the number experiencing a problem increased to 977. Even at five drinks per day, which most agree is too much, the vast majority of people are unaffected.

Some of the risks are...

• Communicable diseases: lower respiratory infections, and tuberculosis;
• Intentional injuries: interpersonal violence, and self-harm; 
• Unintentional injuries: exposure to mechanical forces, poisonings, fire, heat, and hot substances, drowning, and other unintentional injuries; and
• Transportation-related injuries.