The 34-year-old was sharing the photos for National Sunscreen Day in partnership with Naked Sundays, with the message being "to give melanoma the cold shoulder".
"Coming from an ethnic background, being sun smart wasn’t of high importance to my family," Martha wrote. "It wasn’t until I grew up, and I could educate myself that I learnt of the true risks and damage that come from not being sun safe.
"Particularly in Australia, where we have the highest rates of melanoma in the world. Today I’m proud to be a part of National Sunscreen Day, to give melanoma the cold shoulder with @naked_sundays and advocate to you all that being sun smart is the only way to be! Also, Naked Sundays are giving 5% of all sales today to melanoma research and cure."
Her followers loved the photos and the message behind them, with one user writing, "This... I have skin cancer and I live in the UK where I naively never put sunscreen on really as I never felt it was hot enough. Education is so key."
"Iconic," another added, while a third wrote, "Gorgeous Mumma."
"Right on point girl, @marthaa__k I think we need more people to promote sun protection which is extremely important to protect our delicate skin," someone else said.
"Ahhhh you’re so stunning," another added.
Martha's relatable blunder: 'Whoops'
While people loved the photo, Martha had accidentally set the post live without properly editing the caption, leaving the instructions visible for a short period of time.
Instagram account @influencertea_aus spotted the mistake which saw Martha accidentally posting the following: "Hi Gorgeous YAY all approved. Can we ensure this goes live at 7:30/8am on Saturday? Media comment ill use the same as you caption (sic). CAPTION: (small amendments)..."
Martha's followers were quick to alert her to her mistake, with one user commenting, "I think you need to edit the caption love!"
"Well if nothing else you got it posted on time. Baby brain is a real thing," another added.
"Girl whoops," a third said.
"MARTHAAA!! Come edit quick, queen!" someone else wrote.
"Whoops," Martha added. "Thank you to everyone who notified me. Sleep deprivation is real, but let’s not let the message here get lost. This is an important topic for me and something I truly care about. Love you guys."
Her followers loved her response, with one user replying, "We love an honest queen with baby brain."
"I couldn’t relate to anything more if I tried!" another said.
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