Do u think dat having anal sex is dangerous. Do it have after effects? What harm can it cause to the body?

It causes you to forget how to spell and write.

it causes ASSteroids

If you're careful you should be ok. Make sure you and your partner are STD free before doing this and also use plenty of lube and go slowly at first to prevent pain/tearing in the rectum. Be safe and have fun!

"Anal sex, if practised with care, is possible for most couples. It does, however, carry additional health risks and there are safer sexual practices that couples can enjoy. The main health risks, which affect both heterosexual and homosexual couples, are described below.

Human immunodeficiency virus (HIV)
Human papilloma virus (HPV, wart virus)
Hepatitis A (infectious hepatitis)
Hepatitis C
Escherichia coli (E. coli)"
Source and further information:
http://www.netdoctor.co.uk/sexandrelationships/analsex.htm

Further information:
Wikipedia: Anal sex
Top 5 Anal Sex Tips
What Women Love & Hate About Anal

haha
the after afects are that there is sitcky stuff in your ass and your poo is all gnarly
ND WHEN You poo after it kinda hurts haha

Yes, it's dangerous. The anus has more blood vessels, etc. That is why AIDS spread in Africa. They have a tradition of using anal sex for birth control. Bacteria gets into the body through the tears caused by anal sex. Also, it can adversely affect bowel movements for a day or two.

um YES.
STDS/A BABY ARE POSSIBLE after EFFECTS