Here are some studies about dietary aloe vera and photoaging prevention:
Conclusion: Hairless mice were given an oral aloe vera supplement and exposed to UVB irradiation for 7 weeks to evaluate the ability of dietary aloe vera to protect against photoaging. Researchers found that the aloe vera supplement was effective for improving post-UVB exposure skin dryness and wrinkle formation and reduced post-UVB skin collagen degeneration by reducing expression of matrix metalloproteinases, the enzymes responsible for skin collagen breakdown.
Oral Administration of Aloe Vera Gel Powder Prevents UVB-Induced Decrease in Skin Elasticity via Suppression of Overexpression of MMPs in Hairless Mice (2016)
Conclusion: Hairless mice were given an oral aloe vera supplement for 8 weeks and subjected to UVB irradiation for 6 of those weeks to test the photoprotective effects of dietary aloe vera. Researchers found that the aloe vera supplement was significantly effective for reducing post-UVB exposure reduction in skin elasticity and that this is because the supplement effectively reduced expression of matrix metalloproteinases, the enzymes responsible for skin collagen breakdown. These effects were not observed in a control group that received UVB irradiation, but no aloe vera supplement.
Effects of Aloe Sterol Supplementation on Skin Elasticity, Hydration, and Collagen Score: A 12-Week Double-Blind, Randomized, Controlled Trial (2016)
Conclusion: Randomized control trial where 64 healthy, middle-aged Japanese women were given either an oral aloe vera sterol supplement or placebo daily for 12 weeks. Ultrasound analysis of the skin revealed that the aloe group enjoyed significant improvements in skin moisture, skin elasticity, transepidermal water loss, and skin collagen compared to the placebo group.
Effects of Plant Sterols Derived from Aloe Vera Gel on Human Dermal Fibroblasts In Vitro and on Skin Condition in Japanese Women (2015)
Conclusion: Two studies in one
First one: In vitro study found that aloe vera sterols can double collagen production when applied to human skin samples.
Second: Randomized, placebo-controlled clinical trial split 56 Japanese women into two groups, having them either take an aloe vera supplement or placebo daily for 8 weeks. After the study was over the women in the aloe group demonstrated better skin hydration and reduced wrinkle depth compared to the placebo group.
“The present study confirms that daily oral Aloe sterol-containing AVGP [aloe vera gel poweder] significantly reduced facial wrinkles in women aged ≥40 years, and Aloe sterols stimulate collagen and hyaluronic acid production by human dermal fibroblasts.”
Dietary Aloe Vera Supplementation Improves Facial Wrinkles and Elasticity and It Increases the Type I Procollagen Gene Expression in Human Skin in vivo (2009)
Conclusion: 30 older women were given either a low dose or high dose of an oral aloe vera gel supplement for 90 days. The results were that facial wrinkles improved significantly, facial skin elasticity improved, collagen levels increased, and MMP levels decreased. “In this study, we found that aloe vera gel supplementation clinically improved facial wrinkles and elasticity, while it increased type I procollagen and it decreased the MMP-1 gene expressions in the photoprotected skin.”