Scientists discovered that vitamin C from food travels through the bloodstream into every layer of the skin, boosting collagen and skin renewal. People who ate two vitamin C-packed kiwifruit daily showed thicker, healthier skin. The findings suggest glowing skin really does start from within.
Scientists at the University of Otago, Faculty of Medicine Christchurch Otautahi, have identified a direct connection between how much vitamin C people eat and how well their skin produces collagen and renews itself.
The findings show that skin health responds measurably to dietary vitamin C, not just topical treatments. Published in the Journal of Investigative Dermatology, the research found that vitamin C levels in the skin closely mirror levels in the blood (plasma). Increasing intake through vitamin C rich foods was shown to raise both blood and skin concentrations.
Eating Vitamin C Raises Skin Levels and Thickness
The study followed 24 healthy adults in Aotearoa New Zealand and Germany. Participants who raised their plasma vitamin C levels by eating two vitamin C rich SunGoldTM kiwifruit each day showed a clear increase in vitamin C within their skin.
This increase was associated with thicker skin (collagen production) and greater renewal of the outer skin layer.
Lead author Professor Margreet Vissers from Matai Haora — Centre for Redox Biology and Medicine within the Department of
Pathology and Molecular Medicine described the results as striking.
The strength of the association between skin thickness and vitamin C intake is “compelling,” she explained.
Vitamin C Moves From Blood to Skin
According to Professor Vissers, the relationship between blood vitamin C and skin vitamin C stood out compared to other organs.
“We were surprised by the tight correlation between plasma vitamin C levels and those in the skin this was much more marked than
in any other organ we have investigated,” she says.
The research team also found that vitamin C circulating in the bloodstream reaches every layer of the skin and supports healthier skin function. “We are the first to demonstrate that vitamin C in the blood circulation penetrates all layers of the skin and is associated with improved skin function. I am very proud of my team and excited about what the data is telling us.”
Why Diet Matters More Than Creams
Professor Vissers says the findings reinforce the idea that skin health begins internally, with nutrients delivered naturally through the bloodstream.