Since the interest in improving skin appearance and preserving youth is increasing exponentially, and in line with the creation of new cosmetic treatments and topical formulations, it is as good a time as ever to highlight the internal means by which this can achieved.Internal agents are woefully underwritten in skincare when in fact, unlike nearly all of topical agents, these agents are capable of acting on skin through the dermis after they are digested and taken into bloodstream. Topical skin creams and such do not permeate past the epidermis. If the face can be thought of as a house, internal skincare helps to improve skin appearance by repairing the foundation and improving the look of the exterior by re-structuring the interior.
The presented oral anti-skin aging supplements and compounds detailed below can be used alone or used as additives to topical skincare for possible synergistic benefits.
Oral Hydrolyzed Collagen:
Contrary to most beliefs, oral collagen is not useless for skin; in fact, oral collagen has produced statistically significant positive changes in multiple clinical trials. For example, oral collagen supported by other supplementary nutrients (vitamin E, vitamin C, zinc, copper, etc.) was shown to significantly improve wrinkle depth and elasticity. (1) Interestingly, this study also found that wrinkles of greater depth resulted in greater improvement, indicating that the internally-supplied collagen works by restoring collagen levels at the dermis to counteract the aging process at the source rather than the epidermis where shallower surface wrinkles are found. (Ibid). Another placebo-controlled double-blinded study that similarly explored the skin-specific effects of a marine collagen peptide-containing micronutrient supplement found not only a visible amelioration of fines lines and overall skin appearance but also a 78% increase in dermis density by 3 months! (7) A collagen-containing (as hydrolyzed collagen type II) supplement consisting of low-molecular-weight hyaluronic acid and chondroitin sulfate called BioCell Collagen (BCC) was also put through a clinical trial and was found to enhance microcirculation and collagen in the dermis and improve hydration, which resulted in noticeable cosmetic benefits such as decreased facial lines and wrinkles and reduced skin dryness and scaling with daily use of the product (1 g/day) for 12 weeks. (8) A different that study that used collagen peptide supplementation without any other micronutrient supplementation has noted statistically significant elasticity benefits with only 3 g of collagen supplementation daily after 12 weeks. (9) Moreover, other studies have reported increases in skin hydration with ingestion of collagen peptides, probably due to their ability to also increase glycosaminoglycan production. (2-4, 13)
Given the multiple and varied sources attesting to the benefits of oral collagen, it seems that supplemental collagen would be a straightforward and easy method to combat physiological changes with skin aging that overwhelmingly stem from declining collagen formation. Doses from 2.5 g to 10 g appear to be the normal efficacious doses for oral collagen.
Hyaluronic acid (HA) is probably familiar to most people who are interested in skincare now that it is in so many products touting anti-aging benefits as a result of its presence. Hyaluronic acid does indeed possess anti-aging skin benefits, but the problem is its concentration in skincare and makeup products is much too diluted to have any real lasting benefit. Furthermore, “size matters” with HA. Much of these products contain high-molecular-weight HA that does not penetrate beyond the epidermis and as a result, offers inferior moisturizing and anti-aging capabilities. Oral HA is an under-appreciated alternative (or additive) skin remedy. Like collagen, it may not be expected to reach the skin while digested, but a useful portion of HA is in fact transferred to the skin. Out of the number of studies reporting successful skin changes with HA, the recent randomized double-blinded placebo-controlled trial by Kawada et al is a standout. In this study, different supplemental HA sources of differing molecular weights (Hyaluronsan HA-F MW: 800 k / Hyabest MW: 300 k — 120 mg/d) were both found to provide numerous benefits to the participants after weeks including an increase in skin moisture content and improvements in other traits present in a youthful complexion such as suppleness and luster. It was also reported that the lower MW oral HA supplement had better and longer increases in moisture content following the study period. (10)
Hyaluronic acid combines nicely — and theoretically, synergistically — with collagen. Although collagen (and elastin) primarily support skin elasticity, HA that is within the dermis —which is achievable with oral HA, not high-to-average-molecular-weight HA in most products — also contributes to skin viscoelasticity by serving as the fluid matrix that collagen and elastin are embedded in. (Ibid)(11) If elastin and collagen content are supported, it is likely that adding HA will further boost elastin properties of the skin. And unlike collagen, supplemental HA also substantially impacts the moisture content of the skin. Moisture does more than simply make skin look nice and dewy; moisture softens existing wrinkles and helps prevent new ones from permanently forming in the skin after repeated facial expressions. Predictably, improvements in the appearance of wrinkles have been noted with use of oral HA. (12) Hyaluronic acid additionally is involved with tissue repair. (14)Anecdotal evidence also points towards a volumizing effect on the lips. If one has the funds available, oral collagen should be not used as an alternative to HA and vice versa. Supplementing with 120-240 mg of HA daily has shown to be completely safe and effective.
Astaxanthin is a coral-colored carotenoid with profound antioxidant activity. Thanks to the media, it is relatively well known and heralded for its potential in eye protection, but it is equally if not more protective of the skin. By itself, astaxanthin taken orally has shown to confer broad spectrum benefits to skin including wrinkle and elasticity improvement in vulnerable areas such as the “crow’s feet”, increases in moisture and sebum content, and when combined with other helpful anti-aging ingredients (e.g., collagen), decreases in UV-induced upregulation of collagen breakdown enzymes MMP-1 and MMP-12. (15-16) As a carotenoid, astaxanthin should be taken with a relatively high-fat meal. Alternatively, one can look out for astaxanthin in lipid-based formulations. (17) For optimal effects, total oral astaxanthin intake should be at least 2 mg a day, but preferably 6 mg (as 3 mg twice daily based on study results).
Among the carotenoid family, there are a couple carotenoids especially involved in skin protection besides astaxanthin. Such carotenoids deserving of mention are beta-carotene and lycopene. Mostly known as a supplement, beta-carotene can be found in many foods such as carrots, spinach, sweet potatoes, dark leafy greens, pumpkin, squash , and more. Lycopene, on the other hand, is widely known to be in high quantities in tomatoes, although lycopene is rich in other foods including watermelon, papaya, and grapefruit. “Low-dose” beta-carotene supplementation (30 mg/day) was found to significant improve wrinkles and elasticity in female volunteers with evidence of increased collagen production and decreased DNA damage in skin cells. (18) It is crucial to differentiate between low-dose and high-dose beta-carotene supplementation as the “high-dose” (90 mg/day) group revealed increased oxidative stress. (Ibid) With carotenoids, it is a must that physiological but not supraphysiological tissue amounts are achieved as carotenoids do have the potential to generate prooxidant activity if they are mega-dosed.
With lycopene, an even more powerful free radical quencher, oral ingestion has shown to nearly inhibit UVA-induced free radical production in skin. (19) While this study was never published, a published study that gave healthy volunteers 55 g of tomato paste with olive oil and a control group only olive oil daily for 12 weeks similarly reported positive benefits such as increased collagen deposition and a reduction of UV-induced upregulation of MMP-1 (i.e., collagen breakdown enzyme) compared to the control group. (20) It is better that whole dietary sources (e.g., tomato products) are consumed rather than isolated carotenoid supplements as whole compounds such as tomato have a mixture of nutrients that offer greater benefit to skin and better protection against aging UV-rays. For example, tomatoes also contain naringenin, a flavonoid, which stabilitizes the carotenoid and prevents its oxidative degradation. (21) Tomato products also contian other phytonutrients, including phytofluene and phytoene, that contribute to photoprotection. (22) Besides basic antioxidants (i.e., tocopherol/vitamin E), tomato products additionally contain phenolic compounds such as quercetin and chlorogenic acid (23) that could likely account for at least part of the better skin appearance observed with tomato products. Furthermore, lycopene concentrations in skin are significantly inversely related to skin roughness (24), which may be solely attributed to lycopene, or instead, attributed to lycopene plus the mixture of antioxidants and nutrients in lycopene-containing foodstuff. When an oral formula containing tomato extract (28.76 mg) and other skin anti-aging compounds such as marine protein (210 mg of marine complex, composed of fish proteins and polysaccharides), vitamin C (54 mg), grapeseed extract (27.5 mg), and zinc (4 mg) was given to normal male volunteers, significant improvement in multiple skin parameters was reported including hydration, dermal ultrasound density (i.e., increased skin thickness), sun spots, appearance of pores, texture, increased collagen and elastic fibers, and visible improvements in fine lines and wrinkles with daily use after 210 days. (25)
Because all carotenoids are lipophilic, it is important that carotenoid-based supplements are also consumed with fat-containing meals or in a lipid-containing formula for maximal oral bioavailability. Dietary sources of carotenoids also rely on concurrent fat intake to maximize their absorption.
Aloe Vera Gel:
Supplementation with low-dose (1200 mg/day) and high-dose (3600 mg/day) aloe vera gel in healthy volunteers significantly ameliorates facial wrinkles, and in the low-dose group, also improves skin elasticity, with corresponding increases in type 1 collagen in already photoprotected skin after 90 days. (26) Aloe vera is thought to confer such a strong effect on skin due to immunostimulation (i.e., better defense) with polysaccharides, boosts in collagen biosynthesis with acemannan (i.e., a dominant polysaccharide in aloe vera gel), anti-inflammatory glycoproteins, and enhanced superoxide dismutase (i.e., antioxidant) activity. (Ibid) A newer double-blinded, placebo-controlled trial using aloe vera powder (0.5 g in five capsules, containing 40 μg aloe sterols, used daily) in women aged 40 and over (i.e., a time of rapid aging) corroborated with the previous study, finding reductions in wrinkle depth in the aloe vera-treated group with simultaneous worsening of wrinkle depth in the control group within the 8-week study period (27), an expected occurrence with middle-aged skin. These researchers also performed an in vitro study in which they uncovered a 2-fold and 1.5 increase in collagen and hyaluronic acid, respectively, in human dermal fibroblasts treated with aloe sterols cycloartenol and lophenol (Ibid), supporting the results of their human trial. Although the extent of the protection effect of oral aloe vera during continuous UV exposure has not been evaluated in humans, a recent rodent study indicates that oral intake could counteract UVB-induced decreases in skin elasticity and hyaluronic acid content by downregulating collagen degradation enzymes (MMPs) and upregulating adiponectin. (28)
Before deciding to supplement with aloe vera, consumers must be aware that the chosen aloe vera supplement does not contain anthraquinones, as these phenolic compounds can generate reactive oxygen species (i.e., free radicals) in response to UV light, worsening photoaging (27). Aloe vera gel, which is taken from the leaf, does not include anthraquinones For extra precautions, it may be wise to contact the supplement manufacturer for possible inclusion of anthraquinones.
Pycnogenol is a standardized bark extract that comes from the French maritime pine which contains multiple beneficial phenolic compounds that positively affect skin health. In postmenopausal women, 75 mg of pyncogenol taken daily improves skin elasticity, hydration, wrinkles, and smoothness after 12 weeks, and hydration was increased most apparently in those with dry skin. (29) These welcomed changes were accompanied by substantial upregulations in hyaluronic acid synthase-1 (HAS-1) (i.e., an enzyme responsible for synthesis of hyaluronic acid) and gene expression for collagen synthesis. (Ibid) In an ex vivo study, supplementation wit pycnogenol revealed inhibition of MMP-9 (i.e., a collagen degrading enzyme) in human monocytes (i.e., white blood cells). (30)
Skin effects from pycnogenol are also noticeable when pycnogenol is supplemented with a combination of other effective nutrients even with pycnogenol in lower daily amounts (30-40 mg). For example, multi-nutrient supplements such as Viscoderm pearls (total pycnogeol intake: 30 mg/day, also containing collagen , chondroitin sulfate, glucosamine sulfate, and low-MW hyaluronic acid) has shown to improve photoaging, hydration, serum fibronectin (important to the extracellular matrix – roughness, wrinkling, etc.), sebum, and tonicity, and Evelle (total pycnogeol intake: 40 mg/day, also containing vitamin C , vitamin E, biotin, selenium, zinc, bio-marine collagen, silica, blueberry extract, and tomato extract), was seen to benefit elasticity and roughness, respectively. (31-32)
Cocoa products are not so “sinful” as long as antioxidant-rich cocoa powder is consumed as opposed to high-sugar chocolates. In fact, the flavanols in cocoa confer much benefit to skin. Long-term ingestion of flavanol-rich cocoa powder (flavanol content: 326 mg/day) have been proven to increase blood flow to skin, improve its hydration, mitigate its roughness, and increase its thickness. (33) A similar very recent placebo-controlled trial also noted positive effects on skin in women with moderately photoaged skin including roughness, wrinkles, and elasticity with around the same amount of cocoa flavanol intake (320 mg/day) following 24 weeks. (34)
Chocolate lovers need not feel so guilty as long as their cocoa product of choice is high in cocoa over sugar and that these treats are consumed in moderation. Non-chocolate lovers or chocolate lovers looking for more potent effects may supplement with readily available cocoa flavanol supplements.
Carnosine is probably one of the most valuable oral supplements one can take for skin health. Carnosine has already been discussed in detail on this blog for its considerable usefulness as an anti-glycation agent. Besides glycation’s role in diabetes and general aging of the organism, glycation elicits a marked effect on skin aging. Actually, two of the greater facial aging contributors – chronic UV exposure and smoking – mediate their pro-aging effects through glycation reactions. By using carnosine to inhibit glycation, many aging processes can be inhibited at the source.
Based on the results of a randomized, double-blinded, controlled study, participants who were assigned an oral non-hydrolized carnosine formula (Can-C Plus, containing 250 mg of carnosine per capsule) experienced amelioration of several skin parameters including fine lines, smoothness, skin tone, radiance, skin creping, and overall appearance by 3 months. (35) In this trial, carnosine capsules were only taken every second day in modest amounts. It is predicted that higher amounts with daily dosing will achieve even more remarkable effects.
A range of carnosine doses have been utilized and tolerated well in studies, although certain conditions may require more carnosine than an average healthy person would require. To balance safety and efficacy, 200-500 mg of carnosine is an advisable dose in an otherwise person. Since carnosine is found in meat products, vegetarians and vegan may opt for ~500 mg.
Soy and Other Estrogenic Compounds:
This category is especially suited to postmenopausal women who are depleted of estrogen. Skin integrity is dependent on estrogen and estrogen-like compounds that are majorly involved in collagen production, skin thickness, elasticity, and epidermal hydration. (5-6) Soy compounds with estrogen-like compounds or “phytoestrogens” can substitute for natural estrogen to combat the effects of hypoestrogenism on elasticity and collagen, or alternatively, add as an additive for those on HRT.
Equol, a metabolite of daidzein, is produced by intestinal bacteria of the gut after the ingestion of daidzein from soy, but not all humans produce equol, hence its supplementation (with S-equol) is still relevant in those who may still consume healthy helpings of soy in their diet. When S-equol is supplemented in equol “non-producers” in low and high doses (10 mg and 30 mg), significant reductions in wrinkle area (with low and high doses) and significant reductions in wrinkle depth with the high-dose are experienced after 1 month of use in postmenopausal women. (36)
General high soy isoflavone intake is also of great use to skin health. High oral intake of a isoflavone-rich soy extract supplement (100 mg/day isoflavones) was proven to increase skin epithelial thickness and the number of elastic and collagen fibers based on skin biopsies of the postmenopausal participants with 6 months of supplement intake. (37) Another study that used high isoflavone supplementation (70 mg) within a mixed-nutrient drink (also containing: lycopene, vitamin C, vitamin E) with omega-3 fatty acid capsules (660 mg) also documented impressive reductions in wrinkle depth in menopausal women with daily usage for 14 weeks.(38)
Even though phytoestrogen use with soy isoflavones targets postmenopausal women, it is worthy to note that middle-age women can apparently benefit as well. Middle-aged women who supplemented with 40 mg of soy isoflavone aglycone per day experienced a lessening of fine wrinkles and an increase in malar skin elastically by 12 weeks. (39)
Although it is usually olive oil that is casually cited to have beneficial effects on skin aging, it is argan oil that is worthy of the attention. In fact, a recent study involving postmenopausal women compared argan oil consumption (25 mL/day) against olive oil (25 mL/day) and noted that the argan oil group revealed significant increases in several skin elasticity tests. (40) These findings are not at all surprising considering that argan oil actually has higher antioxidant content (gamma tocopherol, ferulic acid, other polyphenols) than olive oil.The remarkable correction of elasticity with argan oil consumption is expected to be explained mainly by the synergistic effects of vitamin E and ferulic acid in the oil. (Ibid)
Argan oil represents an excellent alternative to postmenopausal women or others with decreased elasticity who wish to avoid all estrogen and estrogen-like oral and topical compounds.
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