Eating More Foods with Vitamin C Can Support Skin Thickness and Collagen Production — What the Science Really Says

New research suggests that getting enough vitamin C from foods may help support skin health by increasing collagen production and improving skin structure.

While beauty brands invest billions in anti-aging creams, researchers in New Zealand have found something far simpler: Eating foods with vitamin C could boost the antiaging benefits your skin needs. (ScienceDaily) 

People who ate two kiwifruits daily—the equivalent of 250 micrograms of vitamin C—had thicker skin and accelerated skin regeneration after eight weeks.

The discovery, from New Zealand’s University of Otago, reveals that vitamin C absorbed through the bloodstream travels into all layers of the skin, promoting thickness, regeneration, and a more youthful complexion.

What the Study Found

A 2025 published study in the Journal of Investigative Dermatology investigated how dietary vitamin C affects human skin: (ScienceDaily)

• Dietary intake increases skin levels: Vitamin C consumed through food enters the bloodstream and is transported into all layers of the skin, where it accumulates. (Business Standard)

• Skin thickness improved: Participants who ate two high-vitamin-C fruits daily (SunGold kiwifruit, about 250 mg of vitamin C per day) had measurably thicker skin after eight weeks — a change linked to increased collagen in the dermis.  (ScienceDaily)

• Cell renewal sped up: Epidermal cell regeneration appeared more active after the dietary changes, suggesting better skin repair and turnover. (Business Standard)

The research was funded by New Zealand kiwi grower Zespri International, which had no influence over study design, data analysis, or publication, as well as a University of Otago Research Grant.

Vitamin C’s Role in Collagen and Skin

Vitamin C is essential for the biosynthesis of collagen, the structural protein responsible for skin firmness and elasticity. It acts as a cofactor in the enzymes that stabilize and cross-link collagen fibers. (PubMed)

This is not just topical science — oral intake matters too because the body cannot make vitamin C and relies on dietary sources to maintain plasma and tissue levels. (ScienceDaily)

Diet vs. Topicals

Topical vitamin C can benefit the skin by protecting from oxidative stress and helping support local collagen production, but its absorption through the outer skin layer is limited due to its water-soluble nature. (PubMed)

In contrast, eaten vitamin C enters via the bloodstream and increases levels in deeper skin layers, potentially offering systemic support for collagen synthesis and structural integrity. (ScienceDaily)

Most People Get Enough Through Diet

Primary sources of Vitamin C are citrus fruits, tomatoes, potatoes, Brussels sprouts, cauliflower, broccoli, strawberries, cabbage, and spinach, and it’s very hard to get too much vitamin C, as it passes through our kidneys when we urinate.

Vitamin C supplementation may be needed for people who are deficient due to malnutrition and or a health condition that blocks their ability to get enough of it, such as advanced gastrointestinal disease, cancer, or prolonged poor eating.

Practical Takeaways

• Eat vitamin C–rich foods daily — such as kiwifruit, citrus fruits, berries, bell peppers, and leafy greens — to help maintain high plasma vitamin C levels. (nutritioninsight.com)

• Aim for at least ~200–250 mg/day from food sources to approach the levels used in the study that showed measurable skin changes. (SciTechDaily)

• While promising, the study was relatively small and more research is needed to confirm long-term effects and optimal intakes. (Business Standard)

Balanced Perspective

This research supports the idea that dietary vitamin C contributes to skin structure and collagen formation, but it doesn’t mean vitamin C is a miracle cure for aging skin. Genetics, sun exposure, overall nutrition, and lifestyle factors (like smoking, stress and sleep) all play major roles in skin health. (PubMed)