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Collagen constitutes over 70% of the skin’s dermis. The dermis is the middle layer of skin in the body. It has many important functions, including protecting your body from the outside world, supporting your epidermis, feeling different sensations and producing sweat. The dermis provides structure and support for the epidermis, skin, hair and nails. As a result, the structural integrity of the dermis is vital for the normal function and supple appearance of the skin. As the body’s ability to naturally replenish collagen declines with age, collagen stores decrease.
When looking specifically at eye wrinkle appearance, researchers found that women who ingested 2.5g of collagen peptides over 8 weeks had a 20% reduction in eye wrinkle volume compared to placebo. A significant reduction of 7.2% was found in as little as four weeks. The maximum reduction in eye wrinkle volume at 8 weeks was found to be almost 50% (1).
A second study randomized women into two groups to receive 2.5 g or 5.0 g of collagen peptides or placebo once daily for 8 weeks. Skin elasticity, skin moisture, transepidermal water loss and skin roughness were objectively measured before the first oral product application and after 4 and 8 weeks of regular intake. Skin elasticity (primary interest) was also assessed at follow-up 4 weeks after the last intake of collagen peptides. At the end of the study, skin elasticity in both dosage groups showed a statistically significant improvement in comparison to placebo. After 4 weeks of follow-up treatment, a statistically significantly higher skin elasticity level was determined in elderly women who participated in the study.
While ingestion of collagen peptides and improvement in skin health has been extensively studied, there are fewer human studies examining the relationship between collagen peptides and nail health. Nails are a modified type of skin, and the skin below the nail is known as the matrix. The matrix can be improved by collagen because collagen peptides stimulate growth of the proteins that make up the matrix.
In women with brittle nails, a clinical trial showed ingesting 2.5g of collagen peptides for 6 months improved nail health at 24 weeks for 64% of study participants. Specifically, participants reported nail growth increased by 12% and nail breakage decreased by 42%. These findings indicate that collagen may be of benefit in individuals with weak or brittle nails (1).
Caffeine has a well documented positive impact on cognitive performance such as reaction time, alertness and sustained attention. Researchers found that adults who had low habitual caffeine consumption, when supplemented with 60mg of caffeine, had enhanced sustained attention and alertness, decreased feelings of mental fatigue and reduced reaction time compared with placebo (1). A second study concluded that 75 mg of caffeine improved performance on attention tasks and increased overall mood ratings. Furthermore, caffeine led to a significant reduction in oxygenated hemoglobin in the prefrontal cortex early on in the absorption period and during task performance activities (2).
The European Food Safety Authority (EFSA), an agency of the European Union that provides independent scientific and food safety advice, concluded that a cause and effect relationship has been established between the consumption of caffeine and increased alertness (3).