Which foods should be prioritized to slow down skin aging?

Throughout life, the body's cells are subjected to oxidative stress. This refers to the generation of highly reactive molecules known as free radicals. These are ubiquitous in the process of cellular metabolism and can interact with DNA, proteins, and polyunsaturated fatty acids in the body, causing DNA chain breaks and oxidative damage, protein-protein cross-links, protein-DNA cross-links, and oxidation of lipid metabolism. All these alterations are the primary internal causes of aging and skin dysfunctions.

This observation has led to a medical revolution that has emphasized the role of antioxidants and free radical scavengers in the prevention and management of skin aging. In vivo oxidation eventually leads to the aging of the organism, and exogenous antioxidant supplements, of which diet is a significant source, have become a research topic for several years now.

Thus, to limit skin aging, it is recommended to consume foods rich in antioxidant compounds such as certain vitamins (vitamins A, C, and E), polyphenols, carotenoids, bioflavonoids and trace elements (zinc, manganese, or selenium).

Theindex ORAC (Oxygen Radical Absorbance Capacity) measures the free radical absorption capacity per 100 grams of food. The higher the ORAC index, the more quantitatively the food possesses antioxidant properties. The federal government estimates that Americans consume 4,000 to 5,000 ORAC units per day, equivalent to 2 ½ servings of fruits/vegetables. However, research estimates that people need 12,000 to 13,000 ORAC units to effectively eliminate free radicals!

According to this index, here are the foods richest in antioxidants that should be consumed very regularly to slow down skin aging.

1. Clove

2. Oregano

3. The acai berries

4. The cocoa (powder, unsweetened)

5. Dark chocolate (> 70% cocoa)

6. The powdered curry

7. Turmeric

8. The cooked artichoke

9. Pomegranates

10. The apple (Granny Smith)

11. Cooked Broccoli

Furthermore, the lycopene, a red liposoluble pigment belonging to the carotenoid family, is an excellent anti-wrinkle compound. In a study published in 2008 in the "European Journal of Pharmaceutics and Biopharmaceutics", researchers found that out of the 20 people studied, those with high skin concentrations of lycopene had smoother skin. Consuming more lycopene can also protect the skin from sunburn. This pigment is primarily found in the watermelon, pink grapefruit, and papaya.

Lipids constitute a significant part of the skin and are closely related to the function of the epidermal barrier, the structure of membranes, the balance of the internal environment, and damage repair. Skin aging is accompanied by a decrease in fat content, primarily due to a reduction in the skin cells' ability to synthesize and secrete lipids. Moreover, the amount of dietary lipids ingested is closely related to the body's lipid composition and skin tissues, and an insufficient intake of essential fatty acids or abnormal fat metabolism leads to severe skin diseases. Polyunsaturated omega-3 and omega-6 fatty acids play an important role as human skin barriers and also have certain effects in preventing and treating skin inflammation. In mice, a study has shown that oral intake of olive oil can reduce skin aging induced by chronic psychological stress by acting on the NF-B NRF2 pathway. Also in mice, it has been demonstrated that 7-MEGATM 500 (a product containing more than 50% of palmitoleic omega-7 acid present in fish oil) alleviates skin oxidative stress induced by UV-B rays, inflammation, aging, and promotes skin regeneration.

Other studies have shown that fermented fish oil protects skin aging by inhibiting free radicals induced by fine particles by blocking the Mitogen-Activated Protein Kinase/Activator Protein 1 (MAPK/AP-1) pathway.

In summary, many scientists have proven the effect of dietary fatty acids such as omega-3, omega-6, and omega-7 on skin aging.

Which foods rich in "good fats" should you consume?

Avocados, nuts (almonds, walnuts, hazelnuts...), seeds, fatty fish (salmon, sardines, herring, trout...), sunflower oil, olive oil, sesame oil, flaxseed oil, canola oil, and margarines made from vegetable oil.

Beware, not all fatty acids are beneficial in our diet. Those referred to as saturated are generally best avoided. They are found in fatty meats and processed meats, animal fats, high-fat dairy products (butter, heavy cream, whole milk...), palm oil, coconut oil, many processed foods, and most fried foods.

• BERGER M. M. Can oxidative damage be treated nutritionally? Clinical Nutrition (2005).

• WILLIAMSON G. & al. Skin bioavailability of dietary vitamin E, carotenoids, polyphenols, vitamin C, zinc and selenium. British Journal of Nutrition (2006).

• FRIGOLA A. & al. ORAC and TEAC assays comparison to measure the antioxidant capacity of food products. Food Chemistry (2009).

• SHAW G. Is your diet aging you?Simple strategies to keep you young, inside and out (2014).

• SOYUN C. The role of functional foods in cutaneous anti-aging, Journal of Lifestyle Medicine (2014).

• CHANGWEI CAO & al. Diet and skin aging — from the perspective of food nutrition. Nutrients (2020).