In a year, she was famously sacked from her long-running television morning show on Channel Nine, suddenly appeared on Dancing with the Stars on Channel Seven, and was told she had breast cancer - and survived it.

Three months ago routine medical tests showed the former talk show host had vitamin D deficiency.

''I was quite amazed. I never thought I would be vitamin D deficient,'' Kennerley says.

''I never thought I needed it because I play golf. I'm a girl from Queensland who grew up in the sun.''

Vitamin D deficiency, which has been dubbed the ''silent disease'' has become one of the high-profile conditions that appears to have come about as a result of such strong ''sun safe'' messages.

Without regular sun exposure, bones become deprived of calcium. Brittle bones are then more prone to fractures and could lead to the more serious condition of osteoporosis.

Australia's largest vitamin D study to date was conducted on 24,000 people over two years. The study, released in October last year, found up to 58 per cent of Australians are deficient in the vitamin.

Like many Australians, Kennerley says in the past 15 years she became incredibly careful of her sun exposure.

''Obviously a little too careful,'' she says. ''I had a bone scan 15 years ago and I had fantastic bones. That clearly has deteriorated because I have kept the sun away from my skin.''

Now, the golfer, walker and dancer is careful to get 20 minutes of sun a day before 10am and after 3pm. ''If you are going to go for a walk before 10am, you don't need sunscreen,'' she says.