Avocados are great moisturisers.

"If we eat meat, say chicken, beef or pork, (we will get) collagen (that) is digested and broken down into amino acids to become building blocks of protein in our body to repair broken tissues and skin," he explains.

Dr Koh listed the top five nutrients that promote healthy skin as green tea, vitamin C, lycopene, olive oil, (contains powerful antioxidants polyphenols, which some studies in Japan have found to be helpful in psoriasis and eczema), and nuts, particularly walnuts, pecan and almonds, which are high in antioxidants.

Conversely, the most damaging foods to skin include those with high fat and sugar content, which increases sebum production, leading to acne.

"Foods high in refined carbohydrates such as biscuits, chocolates and cakes also have a high glycaemic index, which increases acne production," Dr Koh adds.

The other foods to be avoided are burnt meat, which contains carcinogens that hike up the risk of cancer, and preserved and processed food like luncheon meat and sausages which have preservatives that can cause skin allergy and rashes.

Generally, Dr Koh advised women to first consult their doctors first before buying ingestible beauty products and to do their research.

-The Star/Asia News Network