Everyone likes to talk about sex, that is, until they’re not having it.

Satisfying, safe sex adds years to the lives of women and men alike, while bringing us closer to our partners.

READ MORE: Eight Ways Sex Makes You More Beautiful

But when your male partner experiences a decreased sex drive,your relationship takes a hit. While women report having less sex drive than they think they should, the truth is, it’s not uncommon for men to have trouble getting into the mood.

If a man has trouble with sexual performance most of the time (not just once every five times) there’s probably a reason for it. Erectile Dysfunction (ED) affects nearly 20 percent of men in the U.S. In fact, a new study finds that problems reaching orgasm are a “regular occurrence even in men without ED.

”The good news is that when you know the cause of your sexual difficulties, you can address it head-on. ED specifically tends to increase with age, and there are tons of (surprising) factors to look out for, ranging from the emotional to the physical. Check out the research behind them to see how you and your partner could fix it.

Problem: “Partner betweenness,” or when a woman comes between a man and his friends, by getting closer to his friends.

How it interferes: Partner betweenness decreases the man’s feelings of privacy and independence with his friends, compromising his concept of masculinity. This can put a damper on relationship satisfaction and attraction. Another possibility is that not having another outlet to confide in can increase conflict in the relationship.

Research: Men whose female partners were more in touch to their confidants were 92 percent more likely to have erectile trouble than a man who was closer to his own friends.

Bottom line: It’s OK to have shared friends, it can even help give a positive sense of “couplehood.” However, giving each other space is essential for your relationship to grow. A couple shouldn’t be “one,” that’s why it’s called a couple! Develop your own interests and friends outside of the relationship. That way, you come back to it feeling refreshed and relaxed.

Problem: Oxidative stress

How it interferes: Free radicals can destroy nitric oxide production (which would otherwise help dilate the blood vessels, getting the blood flow going when you want it to).

Research: Some ED medications increase nitric oxide in the body, though these pills don’t come without side effects. That’s why researchers are hoping to find a more natural means to enhance the function of blood vessels. Antioxidants fight free radicals, so it’s possible that boosting antioxidants can help keep nitric oxide at a healthy level for blood flow.

Familiar polyphenols that increase your own antioxidant power (in your cells) include N- acetylcysteine, coffee, blueberries, walnuts and exercise. Many others may work, but we know these do. The amino acids citrulline and arginine increase your nitric oxide production—a real good thing, as extending your nitric oxide effectiveness is how the little blue pill and its relatives, Levitra and Cialis work.

Researchers are exploring lesser-known agents like lipoic acid, which may be even more effective in sustaining improvements in health. Polyphenols (in chocolate, vegetables and tea) are also of interest, but the findings are too preliminary to say they can be powerful enough to sex drive.

Bottom line: There isn’t a ton of proof that antioxidants can help fertility problems, but DHA (the effective component of fish oil) does. We like to get 900 mg daily from algae (as the fish do!), because you know you’re getting the real stuff. Some minerals may help as well–zinc is being studied, this is still an area in its infancy. Handling stress helps too (try the Cleveland Clinic’s award-winning online stress management program.)

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Problem: Low testosterone from antidepressantsHow it interferes: Not having enough of this sex hormone can lead to decrease sexual desire, which would in turn make it more difficult to be aroused during sex.

Research: Some antidepressants, like selective serotonin reuptake inhibitors (SSRIs), can lower testosterone. Think Paxil, Prozac and other drugs for depression. [Bupropion (marketed as Wellbutrin) doesn’t interfere here, and can help you quit smoking, too.]

Bottom line: Talk to your doctor if you think something in your medical history could be affecting your sex life. It’s not just your hormones that can be affected. An automobile or sports accident you had a long time ago could have left you with injured nerves that affect your sexual functioning today.

Problem: Diabetes, heart problems and/or obesityHow it interferes: Any of these health conditions can affect inflammation, blood flow and hormone levels that need to be at their peak functioning for sexual intercourse.

Research: For obese men with type 2 diabetes, losing 5 percent of their weight boosted sexual desire and alleviated ED within eight weeks. These effects lasted for a year.

Try This: According to the study, there are two diets that can be effective in shedding pounds to get outside of the obesity range.

Low-calorie diet: 900 calories a day

  • A liquid meal replacement (at breakfast and lunch or dinner) with a max of 450 calories
  • The suggested daily allowances of vitamins, minerals and omega-3 and omega-6 essential fatty acids
  • One other small meal

High-protein diet: Reduce diet by 600 calories a day

  • 300 grams of lean meat, poultry and/or fish
  • Three servings of cereals/breads and low-fat dairy products like yogurt and cottage cheese
  • Five vegetable servings
  • Two fruit servings

Bottom line: Drastic diet changes may be necessary if you fall into the obese range. Any healthy lifestyle change that wards of cardiovascular disease and diabetes can help prevent ED too, like regular physical activity, less drinking and no smoking.

It may be an uncomfortable conversation to have with your partner or doctor, but looking at the big picture of what may be causing a sinking sex drive can save your sex life, or life-life!