4. Discussion
Estrogen-deficient, malignant melanoma, hyperpigmentation, breast cancer, merkel cell carcinoma, hair loss, acne
MALIGNANT MELANOMA, HYPERPIGMENTATION, BREAST CANCER, MERKEL CELL CARCINOMA, HAIR LOSS, ACNE
In this 24-week, prospective, randomized controlled trial, 30 g/d of soy protein powder containing 50 mg of isoflavones daily showed significant improvements in wrinkle severity, pigmentation, and hydration at week 24. In addition to sun protective habits such as sunscreen use and sun protective clothing, the current results support the adjunctive use of soy-protein-derived isoflavones for the reduction in skin wrinkles and dyspigmentation such as occurs in skin photoaging. Our study supports the use of a soy-based protein supplement with isoflavones to improve signs of facial skin photoaging such as wrinkles and facial pigmentation in postmenopausal women with Fitzpatrick skin types 1–3. Compared to the casein protein group, the SPII group experienced a significant decrease in wrinkle severity at week 16 and 24, and significant decrease in average pigment intensity at week 24. The mechanism by which soy isoflavones mediate wrinkle severity and pigment intensity may be related to its antioxidative [The finding that SPII supplementation lead to an improvement in the facial pigmentation has support from the literature. Soy-based extracts have been shown to reduce facial hyperpigmentation when applied topically [The SPII group also experienced a significant increase in skin hydration at week 24 compared to baseline in both cheeks. Although this difference was not statistically significant, we chose to present the data as right and left cheeks rather than an overall average as there could be other confounders for variations in the cheeks such as driving-related sun exposure. For example, in the United States, where drivers experience increased ultraviolet (UV) exposure on the left side, malignant melanoma and merkel cell carcinoma were significantly more likely to occur on the left side of the face or arms [Estrogen-deficient skin, such as in postmenopausal women, is characterized by the loss of collagen, elastin, fibroblast function, and vascularity [Interestingly, neither intervention produced significant differences in sebum excretion. While the literature on the associations between soy and sebum production are lacking, one study found that the removal of precipitated casein in lactoferrin, a whey milk protein, led to decreased sebum production [As opposed to topical application, oral supplementation may have other benefits that could be considered an integrative and holistic approach to skin care. For example, soy protein supplementation may have an overall anti-inflammatory effect on the body with a reduction in the circulating IL-6 and TNF-alpha levels [Our findings reveal several potential follow-up studies that would be warranted. For example, future studies should evaluate the role of SPII on other aspects of women’s health that can range from hair loss to acne to vaginal support. The role of supplementation-derived isoflavones vs. food-derived isoflavones should be explored further as well.This study evaluated the use of soy protein containing 50 mg isoflavones and a previous study showed that consuming daily a soy extract containing 100 mg isoflavones improved epidermal thickness and increased collagen and elastin fibers in the dermis [Although some concerns have arisen about the safety of isoflavones, particularly about the impact of soy on women with breast cancer. However, the evidence supports the opposite. Increasing consumption of soy isoflavones was associated with lowered risk for breast cancer in both pre-menopausal and post-menopausal women [