Beauty comes from the inside. The connection between nutrition and skin condition or rather the effect of nutrition on skin aging has been an interesting research field since ancient times. Skin health and aging consists of two distinct processes:
The first is intrinsic skin aging, which represents chronological aging and affects skin in the same pattern it affects all internal organs.
The second is extrinsic skin aging, which we view as aged skin and is the result of external factors and environmental influence, mainly chronic sun exposure and ultraviolet (UV) irradiation but also smoking, pollution, sleep deprivation and poor nutrition.
Prevention is the best and most effective way to work against extrinsic skin aging effects. The best prevention strategy against the harmful action of free radicals is a well regulated lifestyle (caloric restriction, body care and physical exercise for body), with low stress conditions and a balanced nutritional diet, including anti-oxidative rich food.
Frequently researched antioxidants such as carotenoids, tocophenols and flavonoids, as well as vitamins (A, C, D and E), essential omega-3-fatty acids, some proteins and lactobacilli have been referred as agents capable of promoting skin health and beauty. Let´s take a look at them one by one.
L-ascorbic acid (vitamin C)
Vitamin C, also named L-ascorbic acid, is the most important antioxidant. Vitamin C is not naturally synthesized by the human body and therefore adequate dietary intake of vitamin C is required and essential for a healthy human diet.
The richest natural sources are fresh fruits and vegetables such as citrus fruits, blackcurrant, rose hip, guava, chili pepper or parsley. Stability of the vitamin C molecule depends on aggregate condition and formulation.
Tocopherols (vitamin E)
Higher amounts of tocopherol are available in vegetables, vegetable oils like wheat germ oil, sunflower oil, safflower oil and seeds, corn, soy and some sorts of meat. The intake of natural vitamin E products helps against collagen cross linking and lipid peroxidation, which are both linked to aging of the skin.
Carotenoids (vitamin A, β-carotene, astaxanthin, retinol)
Carotenoids are vitamin A derivates like β-carotene, astaxanthin, lycopene and retinol, which are all highly effective antioxidants and have been documented to possess photoprotective properties.
Carrots, pumpkin, sweet potatoes, mangos and papaya are some examples of β-carotene containing fruits and vegetables.
Upon dietary supplementation, β-carotene can be further enriched in skin, in which it is already a major carotenoid.
Lycopene is a bright red carotene and carotenoid pigment and phytochemical found in tomatoes and other red fruits and vegetables, such as red carrots, watermelons and papayas (but not strawberries or cherries). Although lycopene is chemically a carotene, it has no vitamin A activity.
β-carotene and lycopene are usually the dominating carotenoids in human blood and tissues and are known to modulate skin properties when ingested as supplements or as dietary products.
Retinol is important for the human body; however the body itself cannot synthesize it. Retinol must derive from diet. Natural retinol and retinol ester are contained in liver, milk, egg yolk, cheese and fatty fish etc. Naturally occurring and synthetic vitamin A (retinol) show similar biological activities. Different retinol products, both for cosmetic (topical) and pharmaceutical (topical, systemic) use can be found on the market.
In humans vitamin D serves two functions, it acts as a prohormone and the human body can synthesize it itself through sun exposure. Skin is the major site for UV-B mediated vitamin D3, and 1,25-dihydroxy vitamin D3 synthesis. Smaller amounts of vitamin D2 and D3 come from the dietary intake of animal-based foods such as fatty fish or egg yolk. Some products like milk, cereals and margarine can be enriched with vitamin D.
Chang et al. also suggest an association between skin aging and levels of 25(OH)D3, another precursor of vitamin D. It may be possible that low 25(OH)D3 levels in women, who show less skin aging may reflect underlying genetic differences in vitamin D synthesis. Many other studies that tested oral vitamin D treatment showed skin cancer prevention, which is linked to anti-aging effects.
Polyphenols have drawn the attention of the anti-aging research community over the last decade, mainly because of their antioxidant properties, their great intake amount in our diet and the increasing studies showing their probable role in the prevention of various diseases associated with oxidative stress, such as cancer and cardiovascular and neurodegenerative diseases. They are mostly found in fruits and plant-derived beverages such as fruit juices, tea, coffee, and red wine. Vegetables, cereals, chocolate and dry legumes are also sources for the total polyphenol intake.
Curcumin is the principal curcuminoid of the popular Indian spice turmeric, which is a member of the ginger family (Zingiberaceae) and is frequently found in rice dishes to add yellow color to the otherwise white rice. Curcumin has been shown to protect against the deleterious effects of injury by attenuating oxidative stress and suppressing inflammation.
Green tea polyphenols
Green tea polyphenols have been postulated to protect human skin from the cutaneous signs of photoageing. Studies have shown that green tea extract also possesses anti-inflammatory activity. These anti-inflammatory and anti-carcinogenic properties of green tea are due to their polyphenolic constituents present therein.
Ubiquinol (Coenzyme Q10)
Coenzyme Q10 (CoQ10) is a fat-soluble, endogenous (synthesized by the body), vitamin-like substance that is mainly stored in the fat tissues of our body. Primary dietary sources of CoQ10 include oily fish (such as salmon and tuna), organ meats (such as liver), and whole grains. The amount of CoQ10 needed in human organism can be gained through a balanced diet, however in the market CoQ10 is available in several forms as a supplement, including soft gel capsules, oral spray, hard shell capsules, and tablets. As a fat-soluble substance it is better absorbed when taken with fat rich meals. CoQ10 is also added to various cosmetics.
Pre- and Probiotics
The term probiotic is defined as “living microorganisms, which, when consumed in adequate amounts, confer a health effect on the host.”The most commonly used probiotics in humans and animals are enterococci, lactobacilli and bifidobacteria, which are natural residents of the intestinal tract.
A prebiotic is a non-viable food component that confers a health benefit on the host associated with modulation of the microbiota.
Currently, finding alternatives to antibiotics for skin treatment is receiving a lot of interest in research. It has been found that, similarly to the gut microflora, the skin’s microbiota plays a beneficial role. Thus, the possibility to modulate the microbiota more selectively is highly interesting.
Clinical studies that used probiotic bacteria (Lactobacillus johnsonii NCC 533) to modulate the cutaneous immune homeostasis altered by solar-simulated UV exposure in humans suggest that certain probiotics can help preserve the skin homeostasis by modulating the skin immune system.
Essential Fatty Acids (Vitamin F)
Essential fatty acids cannot be produced in the human body and they have to be consumed through our daily dietary intake. They are present in multiple food sources such as fish and shellfish, flaxseed, hemp oil, soya oil, canola oil, chia seeds, pumpkin seeds, sunflower seeds, leafy vegetables, walnuts, sesame seeds, avocados, salmon and albacore tuna.
The association between nutrient intakes and skin aging has been examined: skin-aging appearance was defined as having a wrinkled appearance, senile dryness, and skin atrophy. Higher linoleic acid intakes were associated with a lower likelihood of senile dryness and skin atrophy.
For more information, a planned diet for your skin or if you are suffering from skin problems (such as acne, psoriasis, dermatitis, etc), please contact our doctor here.