A new study shows higher vitamin C intake boosts collagen production, making skin healthier. Vitamin C from foods like kiwifruit enters the bloodstream, reaches all skin layers, and improves skin renewal more effectively than topical creams.
Eating more vitamin C can have a real impact on your skin. A recent study conducted by researchers at the University of Otago’s Faculty of Medicine in Christchurch, New Zealand, has uncovered a strong connection between the amount of vitamin C people consume and how well their skin produces collagen, a protein that helps maintain skin firmness and health.
The findings, published in the Journal of Investigative Dermatology, show that the level of vitamin C in the skin closely matches the levels in the blood. This suggests that increasing the intake of foods high in vitamin C can raise these levels both in the bloodstream and in the skin, with visible results.
Vitamin C Helps Make Skin Thicker and Healthier
The study included 24 healthy adults from New Zealand and Germany. Those who ate two kiwifruit daily for eight weeks, a food known for its high vitamin C content, showed an increase in vitamin C levels in their skin. This increase was associated with thicker skin and faster renewal of the outermost layer.
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Professor Margreet Vissers, who led the study, called the results “striking.” She noted that the link between vitamin C intake and skin thickness was “compelling,” highlighting how important diet is for maintaining good skin health.
How Vitamin C Moves from Blood to Skin
One of the study's most surprising findings was the strong link between vitamin C in the blood and in the skin. The team found that vitamin C from the bloodstream reaches every layer of the skin, supporting its function.
Professor Margreet Vissers said, “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
Although many skincare products contain vitamin C, the study shows that consuming it through food may be more effective than applying it topically. Vitamin C dissolves in water and does not easily pass through the skin's outer barrier, while skin cells can efficiently absorb it from the blood.
The Study in Detail
The research was carried out in two stages. In the first stage, the team studied skin samples from patients undergoing elective surgery at Te Whatu Ora Canterbury, comparing vitamin C levels in the skin and blood.
In the second stage, participants in Christchurch and Germany consumed two kiwifruit daily for eight weeks, providing around 250mg of vitamin C per day. Skin samples were taken before and after this period. In Germany, specialized tests measured skin thickness, elasticity, UV protection, and cell renewal.
Clear Benefits for Collagen and Skin Renewal
The results were significant: participants’ skin became noticeably thicker, indicating higher collagen production, and the outer skin layer renewed more quickly.
Although the study focused on kiwifruit, other vitamin C-rich foods such as citrus fruits, berries, capsicum, and broccoli are likely to have similar benefits.
Daily Intake Is Important
Vitamin C is not stored in the body for long, so maintaining steady blood levels is crucial. For most healthy adults, around 250mg of vitamin C per day is enough to reach optimal levels. Professor Vissers recommends eating at least five servings of fruits and vegetables daily, with one of them being high in vitamin C, as a simple way to support skin health.
The research makes it clear: what you eat can affect how your skin looks and functions. Eating foods rich in vitamin C is not only good for your overall health, it can also make your skin thicker, more resilient, and better at renewing itself. So, reach for a kiwi, an orange, or a capsicum, your skin will thank you.
