DR. WALLACE: I'm 16 and recently started a sexual relationship with the guy I'm eventually going to marry. About three weeks after we started having sex, my face started breaking out. This is the first time I ever had a complexion problem of any kind.

My friend told me that a sexual relationship can cause acne. Is this true? — Nameless, Gary, Ind.

NAMELESS: There is no evidence that sex has anything to do with acne. Your complexion problem and the start-up of a sexual relationship are coincidental. Visit a dermatologist. In all likelihood, the condition can be controlled, if not cleared up completely.

I'd be negligent if I didn't remind you how unwise it is to enter into a premarital sexual relationship. Many negatives haunt such affairs, including contracting a sexually transmitted disease, becoming a mother, and suffering a loss of self-esteem, to name but a few.

IF I PASS THE TEST, I'LL STOP USING POT

DR. WALLACE: I'm a 19-year-old high school graduate and have been laid off from my job and I haven't been able to find another job.

Because of this I have been considering joining the military. My problem is that since I've been out of work I have started smoking a few marijuana cigarettes a week. I can afford them because I receive a weekly unemployment check and I have returned home to live with my parents.

I know that if I decide to go "military" that I would have to pass a physical exam. My concern now would be that marijuana residue would be found in my system. How long would I have to stay away from the weed to be drug clean? Believe me, once I pass the test I will stop using marijuana! — Nameless, Peoria, Ill.

NAMELESS: I hope you're not planning to take your physical in the next couple of weeks, because it takes four to six weeks before THC (the main psychoactive ingredient in marijuana) is completely eliminated from the body. Alcohol, in contrast, is water-soluble and washes quickly out of the body — at the rate of one drink per hour.

THC is fat-soluble and merges with fatty body tissues, thus taking much longer to be expelled from the system. Organs that have high fat content include the brain and reproductive organs. Regular pot smokers are never free from THC.

BEER IS HIGH IN CALORIES

DR. WALLACE: I am sort of a "health food nut." I encourage my mom to cook nutritious foods and to eliminate high-calorie junk foods such as potato chips and greasy foods. So far, everything is working well — all except for the beer (a 6-pack per day) that my dad consumes.

He is trying to convince me that beer is not a bad food because it contains a lot of healthy grains. Is this true? — Nameless, Galesburg, Ill.

NAMELESS: Beer is high in calories and contains no nutrients, no vitamins, no minerals and no protein. Excessive consumption is bad for many reasons, but the most visible one, at least on males, is the beer belly. It's unsightly proof that beer has a lot of calories and no nutritional value.

Tell Dad that if he stopped his beer habit he would save at least $1,095 a year. I have estimated the cost of each beer at about $1 each, but the figure could be higher. This just might encourage your dad to rethink the "healthy" benefits of beer!

Dr. Robert Wallace welcomes questions from readers. Although he is unable to reply to all of them individually, he will answer as many as possible in this column. Email him at rwallace@thegreatestgift.com. To find out more about Dr. Robert Wallace and read features by other Creators Syndicate writers and cartoonists, visit the Creators Syndicate website at www.creators.com.