Most people know that serious, even life-threatening, infections like HIV, hepatitis and other sexually-transmitted diseases (STDs) can be passed from one person to another through sex. One approach to lowering this risk is called "harm reduction." If you do not want to abstain from sex, harm reduction offers options to make sexual activity safer.

Safer sex isn’t only for the prevention of new HIV infections. It’s important for people who are HIV-positive, too. A couple where both partners are HIV-positive can use safer sex to prevent co-infection with other STDs that can weaken the immune system. Safer sex can also reduce the possibility of getting reinfected (also called superinfected) with a strain of HIV that is resistant to the drug regimen you are taking.

Since every sexual act that involves sexual fluids or blood has at least some risk, safer sex means using barriers every time. Barriers include condoms (male and female), dental dams, and even latex gloves. (NOTE: Plastic food wrap may prevent the transmission of herpes infections, but there is no  proof that this type of food wrap will prevent the transmission of HIV.) Barriers help reduce risk substantially.

Even though it is the safest thing to do, some couples do not always use barriers. If this is the case, you can still practice some kind of harm reduction.

Sometimes the place to start in safer sex is to identify the riskiest thing you do and then think about how you could make that activity less risky. The following are some safer sex tips, starting with the most risky activities and moving to less risky activities:

Penetrative sex is considered the highest-risk activity. For both vaginal and anal sex, use latex condoms and lots of water-based lubricant (lube) to prevent the condom from breaking. Lube also helps condoms feel better.

If you’re not going to use condoms, try to reduce the friction by using a heavier lube that will help prevent small cuts or tears in the vagina, rectum or penis. (Because you’re not using latex, Vaseline or Crisco are better than water-based lubes since they last longer.) Also avoid getting semen in the body by having the man pull out before cumming.

Different studies report different levels of risk for HIV infection during unprotected oral sex. However, a number of studies have demonstrated a low but definite level of risk associated with oral sex. To make it safer, use latex condoms for oral sex on a man. If you perform oral sex without a condom, finish up with the hand, or spit semen out and rinse with a dental wash rather than swallowing.

Dental dams are large squares made from latex. (NOTE:  Plastic food wrap may prevent the transmission of herpes infections, but there is no proof that this type of food wrap will prevent the transmission of HIV.)  Put some water-based lube on one side of the dental dam or a condom that has been cut open. Then stretch the dam or condom over the vagina or anus with the lubed side facing down. This gives you a thin barrier between your mouth and the vagina or anus.

If you don’t use a barrier, avoid getting precum, semen or vaginal fluids in your mouth. Avoid vaginal oral sex during menstruation to prevent contact with blood. Bad oral hygiene (bleeding gums, ulcers, gum disease) can make oral sex much riskier. Use a mint instead of brushing your teeth before sex.

Paper cuts and other openings in the skin can make your hands vulnerable to infection. Wearing latex gloves keeps you protected during hand-vagina or hand-anus sex. Adding lube to the outside of the gloves will increase your partner’s pleasure.

Other safer sex tips: Limit the time and frequency of penetrations. Try non-penetrative sex for a change. For example, consider mutual masturbation. Also get medical attention for any infections or health problems in the genital area.

Try and change ways of thinking that make it difficult for you to practice safer sex. The things you think influence how you act.

• Thought: "We slipped once and forgot to use a condom, so it's too late now."
• New idea: It's never too late. Yes, even one exposure can be dangerous, but it's not as dangerous as a hundred exposures! If you slipped once, it's time to get back on the wagon.

• Thought: "Safer sex is such a drag. It's no fun."
• New idea: Here's a great chance to spice up your sex life. Why not take one of the workshops offered on "Eroticizing Safer Sex?" How about getting a book, video, or DVD about hot safer sex?

• Thought: "I can't feel anything through condoms!"
• New idea: Time to change brands! Getting free condoms at the health office or buying them at a drugstore may be cheap, but you're probably not getting the best around. Try some of the variety packs offered by mail-order sex supply catalogs or hit the "adult love" stores in your area for a better selection. The best condoms are thin but tough and transmit heat and sensation well.

• Thought: "My partner absolutely refuses to use a condom."
• New idea: How comfortable are you with someone who is willing to put your life at risk? This sounds like a serious issue, and it's probably not the only one in your relationship. Have you considered individual or couple's counseling?

• Thought: "I can't suggest to my girl/guy that we get an HIV test. We've been together so long that s/he would take it as an insult."
• New idea: How about presenting it as an act of love? "You know, I really love you. We've been together for awhile, but we never got tested for HIV. I hate the thought that I could be putting you at risk, because I couldn't stand to hurt you. Why don't we go get tested together for our peace of mind?"

Sometimes the safest thing you can do in sex is keep a clear head. Sex when you are drunk or under the influence of drugs may be most likely to be unsafe.