Dr Gabby Maston Nutrition & Obesity Services

Do you want healthy-looking skin and a glowing complexion? Well, the appearance of your skin may be less about the serums, creams, and lotions you use on the outside and more about the quality of your diet. The adage -you are what you eat, has never been so true!

The skin is the largest organ in the human body. It regulates body temperature, signals sensations of touch and produces vitamin D, which contributes to the development of bone, and immune and vascular health (1). Its appearance is affected by the following factors: diet, sleep, exercise, sunlight, age, smoking, gender, environmental pollution, some medical treatments, and chronic health conditions. In this article, I am going to focus on the dietary factors that affect the appearance of your skin. Remember, some of the big-ticket items you can do to improve the appearance of your skin are to protect your skin from sun damage by wearing sunscreen and quitting smoking if you smoke. Without these fundamentals, dietary changes will make little difference.

Skin and ageing

Chronological ageing of the skin is inevitable after a certain age. Factors such as genetics, ethnicity, and the skin site affect the appearance of your skin due to ageing and unfortunately, this is something you cannot control. Ageing is associated with dry skin, dullness, lack of elasticity, and fine wrinkles (2).

In contrast, photo-ageing is skin ageing due to long-term exposure to UV rays. This appears as wrinkles, relaxation, roughness, yellowish or greyish-yellow, capillary expansion, and pigmented spot formation (2)

Nutrition for healthy-looking skin

Nutrition is closely linked to skin health. Nutrition can repair damaged skin and can also cause damage to the skin (2). For example, there are many vitamin deficiencies that affect skin health and can cause skin disorders. For example, lack of Vitamin C can cause scurvy which presents itself as fragile skin and poor wound healing. Vitamins are mostly ingested from the food we eat so the vitamin content of your diet is closely related to your skin’s capacity to maintain and protect itself.

Nutrition and skin damage due to sunlight (photo-ageing)

The skin is a light-sensitive organ, and it requires some light to function properly. Excessive amounts of light can cause permanent damage to the skin leading to cancer and presenting itself as wrinkling or skin ageing. Following the recommendations of spending 20 minutes every day exposing sunscreen-free skin in the early morning (typically before 9am) or late afternoon (after 5pm), is enough sun exposure for your skin to produce the required levels of vitamin D. Outside of these low UV index times, and for longer durations without sunscreen applied may be causing sun damage and photo-ageing over time.

The World Health Organisation recommends protecting the skin from the sun when the UV Index is 3 or higher. The UV index for different regions is typically reported during weather reports. If you have an iPhone the UV index can be viewed in the weather app.

Skin damage caused by exposure to UV rays in sunlight is called actinic keratosis. It is also known as solar keratosis. It appears as a rough, scaly patch or bumps on the skin and sometimes these lesions can develop after a period into skin cancer. You may not be into sun tanning or tanning beds, but damage to the skin due to sunlight builds up over time. This means a daily mid-day walk or regular weekly gardening without sunscreen over time can put you at risk of actinic keratoses and skin cancer.

One international study has investigated dietary intake, skin wrinkling and exposure to UV rays. In this study, four groups of people were observed, Greek-born subjects living in Melbourne, Greek subjects living in rural Greece, Anglo-Celtic Australians and Swedish subjects living in Sweden. This study found that skin wrinkling in a sun-exposed site, in this case, it was the back of the hand, in older people from a variety of ethnic backgrounds is influenced by the type of food they ate. Swedish elderly had the least skin wrinkling, followed by Greeks in Melbourne, Greeks in rural Greece and Anglo-Celt Australians.

There are obvious genetic differences between the groups, but researchers did find that diets with a higher vegetable intake, olive oil, legumes, and fish were protective against skin damage (3). This held true even after controlling for variables such as age, gender, and smoking status which we know are typical things that affect the appearance of skin. High intakes of meat, butter and full-fat dairy appeared to have negative effects on the appearance of skin.

Researchers believe that the healthy foods listed may be protective against skin damage due to the protective nutrients they contain and their high levels of antioxidants, vitamins, and phytochemicals, for example, vitamin C, retinol, calcium, phosphorus, magnesium, iron, and zinc. Consuming a diet high in vegetables, legumes and olive oil are protective against oxidative stress.

Skin is susceptible to oxidative stress leading to oxidative damage because it is made up of fats, proteins, and DNA. In European cuisine, which includes Greek cuisine, vegetables and legumes are consumed with olive oil. This combination of foods may provide further benefit in preventing skin wrinkling because of the combination of healthy unsaturated fats from the oil that helps the absorption of fat-soluble antioxidant vitamins and phytochemicals, such as vitamin E, lycopene and isoflavones. Fruits, herbs, and tea are also rich sources of phytochemicals, which could be beneficial to include in your diet.

To add weight to this argument another Dutch study found that women who ate a diet rich in fruit, low-fat yogurt,  low-fat milk, and vegetables had fewer wrinkles than women who ate a diet that was mainly meat-based, contained refined grains, snacks, soft drinks, coffee and alcoholic drinks (4). In another study of Japanese women, a higher intake of green and yellow vegetables was linked with less wrinkling and a higher intake of saturated fat was linked with more wrinkling (5).

The results from these studies are unsurprising. Fruits and vegetables, especially yellow and red pigmented types are high in Vitamin A precursors, in particular retinol and retinyl esters. Vitamin A and Vitamin A precursors have been shown to have a strong capacity to absorb UV rays (6). Retinoids have been shown to improve the appearance of aged skin, reduce skin wrinkling, increased smoothness and decrease hyperpigmentation of skin (6). Below are a list of foods you may want to include in your diet

Water intake

Water is vital to the human body. A lack of water in the body can cause skin tissue dehydration, ageing, and inflammation. The appearance of the skin on lips and limbs is a direct reflection of the body’s moisture status. Studies have shown that drinking more than 2 Litres of water per day can improve the hydration of your skin both superficially and deep hydration (2).

Whole food plant-based diets and skin health

By now you should be convinced that following a predominately plant-based whole foods diet is the best skincare routine you can adopt. Plant-based foods are rich in polyphenols, carotenoids, minerals, and vitamins that are otherwise not found in other foods. Plant-based foods have a unique combination of compounds that work together to protect the condition of your skin (1). The benefits of this superior nutrition are that it can improve skin hydration, hyperpigmentation, wrinkles, erythema, collagen, and elasticity (1).

Plant-based diets are high in Vitamin C and Vitamin C has an active role in collagen synthesis and influences skin hydration (6).

Food sources of Vitamin C

• Citrus fruits
• Blackcurrant
• Strawberry
• Raspberry
• Kiwi
• Cruciferous vegetables (Brussels sprouts, kohlrabi, broccoli, cabbage, cauliflower), spinach, chicory, green bean, red pepper, chives, parsley, nettle, and oregano)

Plant-based diets are also high in Vitamin E. Vitamin E important role in maintaining skin health, it protects the skin from oxidative stress caused by the environment, and it has a role in collagen production (6). Some research also indicates that vitamin E has some protective effect against UV rays, is firming, hydrating and has anti-aging properties, as well as improving the elasticity, structure, and softness of the skin (6).

Food sources of Vitamin E

• Wheat germ oil
• Sunflower oil
• Safflower oil
• Soybean oil
• Maize oil
• Cottonseed oil
• Nuts

Other useful compounds found in high amounts in plant-based diets are carotenoids and polyphenols, such as apigenin (a flavonoid occurring in numerous herbs, fruits, and vegetables), quercetin (a flavanol found in onion skin and apple peel), curcumin (found in turmeric), genistein (an isoflavone from soybeans), proanthocyanins (from the seeds of grapes), and resveratrol (found in grapes, peanuts, fruits, red wine and mulberries) (6).

Supplemental foods

Caffeine

Drinking caffeine-based products might improve the appearance of your skin. In one Japanese study, the effect of chlorogenic acid consumed from coffee was studied (7). They found there was an association between higher consumption of coffee (450 mL/d) or coffee polyphenols (900 mg/d) with lower skin hyperpigmentation in women. Daily consumption of a decaffeinated beverage containing 297 mg of coffee polyphenols for 4 weeks significantly improved scaly skin in the cheeks and around the mouth (8).

Collagen peptides

Collagen peptides mainly come from animal skin, bones, tendons, muscles, and other tissues (2). Collagen is found throughout the entire human body and skin is predominantly made up of collagen. As you age, your body produces less collagen, leading to dry skin and wrinkles. But before you think about supplementing with collagen peptides, think about improving your diet first by increasing your intake of Vitamin C intake through food. Vitamin C is crucial for collagen synthesis.

If your diet is up to speed, collagen peptides supplements may be something you would like to add to help slow the ageing of your skin by reducing wrinkles and dryness. One study found that taking 3–10 grams of collagen per day for an average of 69 days led to improvements in skin elasticity and hydration. Collagen supplements may work by stimulating your body to produce its own collagen. Additionally, collagen supplements may promote the production of other proteins that help structure your skin, including elastin and fibrillin (9).

Cocoa

The daily consumption of a cocoa beverage containing 320 mg of

flavanols for 24 weeks significantly improved measures of skin elasticity, as well as skin roughness, which appears as an improvement in wrinkle depth (10). In addition, intake of a cocoa beverage containing 329 mg of flavanols for 12 weeks significantly decreased UV-induced erythema, skin roughness, scaling, and increased skin density, thickness, hydration, and blood flow to the skin tissues in women aged 18 to 65 (11).

Do you need help making these improvements to your diet? Book an appointment with Dr Gabby to learn how to include all these healthful skin-promoting foods in your diet.

References

1.         Fam VW, Charoenwoodhipong P, Sivamani RK, Holt RR, Keen CL, Hackman RM. Plant-Based Foods for Skin Health: A Narrative Review. J Acad Nutr Diet. 2022;122(3):614-29.

2.         Cao C, Xiao Z, Wu Y, Ge C. Diet and Skin Aging-From the Perspective of Food Nutrition. Nutrients. 2020;12(3):870.

3.         Purba Mb, Kouris-Blazos A, Wattanapenpaiboon N, Lukito W, Rothenberg EM, Steen BC, et al. Skin Wrinkling: Can Food Make a Difference? Journal of the American College of Nutrition. 2001;20(1):71-80.

4.         Mekić S, Jacobs LC, Hamer MA, Ikram MA, Schoufour JD, Gunn DA, et al. A healthy diet in women is associated with less facial wrinkles in a large Dutch population-based cohort. Journal of the American Academy of Dermatology. 2019;80(5):1358-63.e2.

5.         Nagata C, Nakamura K, Wada K, Oba S, Hayashi M, Takeda N, et al. Association of dietary fat, vegetables and antioxidant micronutrients with skin ageing in Japanese women. British journal of nutrition. 2010;103(10):1493-8.

6.         Michalak M, Pierzak M, Kręcisz B, Suliga E. Bioactive Compounds for Skin Health: A Review. Nutrients. 2021;13(1):203.

7.         Fukushima Y, Takahashi Y, Hori Y, Kishimoto Y, Shiga K, Tanaka Y, et al. Skin photoprotection and consumption of coffee and polyphenols in healthy middle-aged Japanese females. International journal of dermatology. 2015;54(4):410-8.

8.         Ueda S, Tanahashi M, Higaki Y, Iwata K, Sugiyama Y. Ingestion of Coffee Polyphenols Improves a Scaly Skin Surface and the Recovery Rate of Skin Temperature after Cold Stress: A Randomized, Controlled Trial. J Nutr Sci Vitaminol (Tokyo). 2017;63(5):291-7.

9.         Choi FD, Sung CT, Juhasz ML, Mesinkovsk NA. Oral Collagen Supplementation: A Systematic Review of Dermatological Applications. J Drugs Dermatol. 2019;18(1):9-16.

10.       Yoon H-S, Kim JR, Park GY, Kim J-E, Lee DH, Lee KW, et al. Cocoa Flavanol Supplementation Influences Skin Conditions of Photo-Aged Women: A 24-Week Double-Blind, Randomized, Controlled Trial. The Journal of nutrition. 2016;146(1):46-50.

11.       Heinrich U, Neukam K, Tronnier H, Sies H, Stahl W. Long-Term Ingestion of High Flavanol Cocoa Provides Photoprotection against UV-Induced Erythema and Improves Skin Condition in Women. The Journal of nutrition. 2006;136(6):1565-9.