Bacteria and skin don't sound like a great combination, but in fact the right balance of micro-organisms in and on your skin keeps it healthy.

We hear lots about our gut microbiome and how vital the health of this collection of trillions of micro-organisms – bacteria, viruses, fungi, yeasts and parasites – is to physical and mental health. Skin, too, has a microbiome, which keeps it healthy – or not, as it’s constantly under threat from environmental and lifestyle factors. Preferring a slightly acidic pH of 5, the skin microbiome protects against infection, assists wound healing, limits exposure to UV rays and allergens, and reduces oxidative damage.

University of California researchers discovered that an important part of the skin microbiome is established within days of birth. During this time significant T-cell activity occurs, which is a critical factor in training the immune system not to attack the normal, healthy bacteria living on the skin. Antibiotics given to the mother during labour, or to mother and baby post-birth, affect the type of bacteria seen by the adaptive immune system, and may be linked to subsequent development of autoimmune inflammatory skin diseases. For example, people with eczema lack many of these antibiotic micro-organisms within their skin. Here's how to promote a healthy skin biome in older children and adults.

1. Get down and dirty We need contact with soil-based organisms, which are the natural strains of probiotics present on skin and in the gut. Gardening is the best way to do this. Do what you can, even if it’s growing herbs in a window box, and spend time outdoors in nature, with some contact with the earth: hiking, camping, even sitting on the grass in a park while eating lunch.

2. Be gentle Rather than seeing skin as something that must be scrubbed clean to get rid of 'germs', regard it as a part of the body to be gently nurtured. Everything you put on your skin can change its natural pH and the balance of micro-organisms, for better or for worse, so avoid antibacterial soaps, cleansers, hand sanitisers, shampoos, and wipes, especially those containing triclosan or triclocarban. These chemicals contribute to skin dysbiosis, which is associated with eczema, psoriasis, rosacea acne, poor wound healing, dandruff, yeast and fungal infections. Use soap only if it’s essential, and ideally choose a natural Castile soap. Buying liquid Castile soap in bulk saves money, and it can be used for all sorts of cleaning jobs.

3. Wash dishes by hand A Swedish study found that in families where dishes are washed by hand, allergic diseases in children were less common than in children from families who use a dishwasher. The authors believe that a less-efficient dishwashing method may induce tolerance via increased microbial exposure.

4. Add probiotics to skincare Break open a probiotic capsule and mix the contents into your facial and body moisturisers.

5. Care for your gut Take a quality probiotic as well as a prebiotic, such as slippery elm. Consult a qualified natural therapist to ensure you use the right strains, as your requirements constantly vary.

6. Break a sweat! Whether through exercise or sauna, sweating promotes skin health by functioning as a prebiotic.

Ann Vlass BSc(Hons) BHSc(Nat) is a Member of The Australian Traditional Medicine Society.