It's good to want to be healthy — especially at the start of a new year. Considering less than 1 in 10 Australian adults meet their daily recommended intake of vegetables, you should thank yourself every time you make a salad.

But other 'healthy' daily habits are not that healthy after all. They could even be bad for you.

Using cottonwool buds to clean your ears

Ear wax is normal, harmless and it helps protects your ears from infection. Some people, however, like to stick cottonwool buds in their ears as though they're mining for gold.

You should never put cotton buds, fingers or any other objects in your ear because this can push wax in further, and you could damage your ear. If you suspect you have a large build-up of ear wax or your ear is blocked, see your GP or practice nurse, who can painlessly syringe it out using warm water.

Showering twice a day

Healthy skin has a layer of oil and a balance of good bacteria and microorganisms. Bathing too often can upset this balance, leading to dry, irritated or itchy skin, and killing off normal bacteria.

One poll found Australians shower, on average, 8 times a week. If you're showering twice a day, it's probably too often (especially during a drought). Some experts even believe that most people don't even need to shower every day.

Using antiseptic cream on wounds

If you're a parent, you might think you're doing the right thing by applying a little Betadine to your kid's scrape. But antiseptic creams or solutions are not recommended for wounds you treat at home — thoroughly cleaning the site with water is enough to reduce the risk of infection.

According to the Royal Children's Hospital Melbourne, strong antiseptic products containing hydrogen peroxide or iodine can actually cause tissue damage. Antiseptic creams can be irritating to wounds and delay healing (and are sometimes painful).

Unless you've been specifically told to use them by a nurse or doctor, leave the antiseptic stuff in the medicine cabinet.

Going straight for the hand sanitiser

'Antibacterial' hand sanitiser might sound like the safer bet, but studies show that hand washing with plain soap and water is more effective at destroying germs such as Cryptosporidium, noroviruses and influenza.

That said, if you don't have access to soap and water, hand sanitiser containing alcohol is an excellent alternative.

Popping multivitamin supplements

With a few exceptions — including folic acid for pregnant women — there is no evidence that vitamin supplements make any difference to the health of most people. Multivitamins are considered by many experts to be a waste of money. It's better to get all the vitamins and minerals you need from a healthy, balanced diet.

Note, supplements can be dangerous if you take too much of any one vitamin or mineral. High doses of vitamin C can cause diarrhoea and kidney stones, for example, while high doses of vitamin A can be toxic.

Rinsing with mouthwash

You brush your teeth with the skills of a Renaissance painter, floss religiously and swish with mouthwash. Sounds healthy, right? Your daily mouthwash habit, however, might be doing your mouth more harm than good.

There are myriad types of mouthwash with many different ingredients. Some come with adverse effects while others have been shown to work no better than a placebo (they just make your mouth feel clean). There is even a link between mouthwashes that contain alcohol and oral (mouth) cancer.

Of course, some types of mouthwash can help control plaque and gingivitis, especially in people who aren't able to properly brush and floss. Figuring out which one, if any, is right for you is complex and best done with the help of a dentist.

Going green with reusable handkerchiefs

It's good to opt for reusable over single-use products where possible (straws and coffee cups, for example) but old-school hankies might be an exception. The cold and flu viruses that live in the droplets from blowing your nose or sneezing can survive for hours on surfaces — even on fabrics. It's best to use a tissue and throw it in the bin straight away.

Drinking kombucha

This fermented drink has become a popular substitute for soft drinks and juice, but like those beverages, kombucha is acidic, meaning it can wear away the protective enamel of your teeth.

And, according to the NSW Food Authority, many brands of kombucha and other fermented drinks such as ginger beer and kvass contain alcohol — a by-product of the fermentation process. Some even contain enough to be considered an alcoholic drink.

Children, women who are pregnant or breastfeeding, people who take certain medications and people who intend to drive should be aware that fermented drinks may increase their blood alcohol level.