Elle Macpherson: "It's one thing to be 20 and gorgeous... and there's another thing to be 51 years old".

She was one of the original supermodels alongside Naomi, Christy and Linda, but now that’s she’s 51, Elle Macpherson has realised that her looks are secondary to how she feels inside.

Speaking to Sunrise while in Australia for a quick trip to promote her health product, Super Elixir, the Australian supermodel spoke about her body confidence.

There’s one thing being 20 and gorgeous with legs up to your armpits and beautiful tight skin, and there’s another thing to be 51,” she explained to Samantha Armytage. (Post continues after gallery.)

And the model-turned-businesswoman has some great advice for anyone feeling a similar way as they get older.

“Finally you get to the stage and say, I have been known to be one of the most beautiful women in the world and felt really not confident and sure of myself,” she explained.

“And as I’ve matured, what I realise is it doesn’t really matter what I look like, the most important thing is how do I feel.”

Now, Macpherson says she pays a lot more attention to staying healthy from the inside.

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“When I started sleeping more and relaxing a bit more in my life and looking after my nutrition… good nutrition can change everything. I hadn’t really understood how deprived my body was,” she said.

But despite this, it’s refreshing to hear that the mother-of-two has a healthy attitude when it comes to treating herself too.

“I don’t think it’s naughty, so yes I do,” she said when asked if she ever gives into temptation with more high-calorie foods. “I have a sweet tooth.”

The 51 year-old has previously spoken to Get The Gloss about how important it is to take time for yourself.

"I block out 50 minutes a day to do something for my body - it could be a wrap, going to the gym or a swim. One day I might meditate, another I might write, or I might have a wax. I try to make at least four of them in a week," she said.

She also revealed that while she doesn't train, she really enjoys sport.

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"I really believe that when you combine the fun with the physical benefits it doubles the impact. So when I pick my exercise I choose a sport I love or choose something I want to master - yoga was something I wanted to get better at recently."

"I also love swimming, and I waterski, ski, windsurf, paddleboard, swim laps round the reservoir or I go for a run," she shared. (Post continues after gallery.)

When it comes to the Elle Macpherson secret? It's surprisingly practical - staying hydrated, adequate sleep and plenty of greens.

We asked The Glow office what body image advice they'd give their 20 year-old selves. The results are moving, uplifting and hilarious all at once. 

Do you worry about getting older? What lessons have you learned as you've matured?