While the weight of a person affects their general health, there is no direct effect of weight on chances of death - it is more an effect on outcomes should a person develop a disease or condition.
That would be Warrick Brown.
Who is the first person to die in the railway?
Dead
Slim Brundage died in 1990.
Lightnin' Slim died in 1974.
Slim Jones died in 1938.
Slim Harriss died in 1963.
Slim Wintermute died in 1977.
Slim Aarons died in 2006.
Slim Emmerich died in 1998.
Alberta Slim died in 2005.
Slim Smith died in 1973.