32 suicides in Russia versus 1 suicide in Peru per 100,000 people per year - How do you explain the greatly varying suicide rates in different countries?

Here’s a list of countries taken from

http://en.wikipedia.org/wiki/Suicide_rates

Lithuania: 39
Belarus: 35
Russia: 32
Hungary: 26
Japan: 24
South Korea: 22
Finland: 20
France: 18
China: 14
Germany: 13
United States: 11
India: 10
United Kingdom: 7
Israel: 6
Brazil: 4
Philippines: 2
Kuwait: 2
Peru: 1

Men kill themselves about 3 to 6 times more often than women. Why?

A notable exception is China, the only country where more women than men commit suicide. Quite strange.

I’ve heard that widespread alcoholism might correlate with higher suicide rates and I’ve also heard that Catholicism might correlate with lower suicide rates. I’m not sure how good the evidence is. What is your opinion?