Experts agree, it's important to maintain our bodies in order to have a healthy sex-drive. [Agencies]

Want to have more and better sex? If you eat well and stay in shape, you could be doing it well into your 70s and 80s, say the experts.

Just as a car needs an oil and lube to keep it running, we need to look after our body parts to keep our sex drive running hot. What we put into our bodies, and how we take care of ourselves, go a long way to taking care of business in the bedroom.

Naturopath Cushla Reid says a healthy diet helps the production of phenethylamine – a "love chemical" which helps create feelings of excitement.

"Phenylethylamine is known as the 'love drug'. It is a chemical that mimics the brain chemistry of a person in love and is believed to be the body's natural version of amphetamine," she says.

To maintain production of this love drug we need to eat well and stay hydrated, she says.

"Hydration is so important. Sex is like a game of tennis – it can go on for quite some time and be pretty hot and sweaty, so if you're dehydrated you'll tire easily and it'll be game over all too soon."

Avoid a diet high in saturated fats, such as junk foods and too much red meat, she says. These will clog you and slow you. Instead, make sure you get plenty of foods rich in vitamin A, such as apricots, avocados, carrots, dark green and deep yellow vegetables, and vitamin E, such as fish oils, vegetable and flaxseed oils, and nuts.

Vitamin B, found in such foods as dark leafy greens, grains and cereals, is also good for feeling frisky.

Food with zinc, such as oysters, liver, ginger root and eggs, are especially good for men, she says.

Low zinc levels in men can lead to impotence, low sperm count and a loss of interest in sex. The right zinc levels (up to 100 milligrams daily) will increase male fertility and sex drive. But don't overdo it, she warns, as too much zinc can reduce immune function.

Reid also recommends food high in vitamin B3 for a healthy sex life – red chilli peppers, liver, kidney, sesame seeds, pine nuts, and even coffee.

"Vitamin B3 causes the veins to dilate and help the blood flow, which is especially good for men."

Robyn Salisbury, clinical psychologist and director of Sex Therapy New Zealand, says we could be enjoying a happy and active sex life well into our 70s and 80s if we look after our bodies.

"The better you treat your body, the better it will treat you. When we are younger, we can get away with having a horrific diet and still having a good sex life.

"But when we are older, we need to look after our health and wellbeing if we want good and frequent sex," she says.