As important as it is to be mindful about what you put on your skin, through clean skincare products, we want to share the importance of what you put into your body as well! Anything we ingest becomes a part of our cells, and can ultimately contribute to the health of our skin. In general, what we see on the outside is an indication of what is going on inside the body, specifically in the gut (the gut-skin axis). Below we have outlined the top five foods to be wary of and others to continue eating for clear, healthy skin that ages gracefully.

 5 Foods to Avoid or Consume in Moderation

 Dairy

 Yes, this includes our beloved cheese. For those with sensitive skin, dairy could be an underlying food sensitivity. The difference between a food sensitivity and food allergy is that a sensitivity may be subtler (ie. presenting in your digestive system or as a chronic skin condition), while an allergy often presents as an immediate reaction with hives, itching, with potentially more serious symptoms such as swelling in the throat.

Dairy can contribute to inflammatory skin conditions, and has been heavily implicated in acne. This is because it causes an increase in insulin, the hormone which is released after we eat so we can effectively use carbohydrates as energy. More importantly, with this increase in insulin comes and increase in insulin-like growth factor-1 (IGF-1) which can cause increases in oil production on the skin, and inflammation of follicles [1]. This reaction is even more exaggerated in dairy products that are further processed to get rid of fats, such as skin milk, suggesting that milk itself may be chemically and hormonally active [2].

Processed Foods

More specifically, this subheading relates to foods that have a high glycemic load. Glycemic load refers to the amount of carbohydrate in a particular food and how quickly it affects blood sugar levels once it is eaten. Foods with a higher glycemic load are those which are heavily processed, often pre-packaged (ie. artificially sweetened foods, baked goods, fast food) or carbohydrate sources that are low in fiber, such as white grains, pastas, and bread. These can affect the skin, similarly to dairy products. With high glycemic foods, there is a faster spike in blood sugar levels, so a faster spike in insulin and IGF-1 [3]. This causes androgen levels in the body to increase, and can contribute to more oil production and clogging of the skin’s pores [2]. Androgens are reproductive hormones which both males and females make, although men produce more of them which is why they are often labelled as the “male hormone”.

Fried Foods

Fried foods or those that are heated at high temperatures through grilling, barbequing, searing or toasting can be harmful for the skin. This is because they produce something called advanced glycation end products (AGEs), which are what form when proteins and/or fats fuse with reduced sugars in the bloodstream. AGEs are cleared through body through neutralization with antioxidants in the diet, but if overeaten can accumulate. AGEs can affect the body in a variety of ways causing inflammation and oxidation which contribute to heart disease and diabetes [5]. Additionally, it seems that AGEs can accumulate more in the elastin and collagen of the skin [4]. These skin fibers are what allow the skin to retain moisture and keep its firm structure. When there is a buildup of AGEs in the skin, it can accelerate aging of the skin, which can present as fine lines, uneven complexion and dullness of the skin’s tone.

Processed Meats

Processed meats such as hot dogs, sausages, bacon, cold cuts, and cured meats can be damaging to the skin and accelerate its aging. This is because these products contain a lot of sodium and other preservatives such as nitrites and sulfites. The World Health Organization released an statement saying that processed meats are a carcinogen food, meaning that they have the potential to contribute to increased risk of certain cancers; colorectal, pancreatic and prostate, specifically [6]. This means that they can cause inflammation if overeaten at 50g of processed meat per day. Additionally, these meats are high in AGEs even without being cooked, which can cause further inflammation and weaken collagen in skin, causing fine lines and signs of aging.

Alcohol

Alcohol can contribute to poor skin quality in a variety of ways, with excessive intake being related to chronic skin conditions such as psoriasis [7]. This is mostly due to liver congestion, or difficulty clearing alcohol from the body, which causes inflammation of the skin. Another important piece of information to note is that any alcohol consumption at all can cause dehydration. Alcoholic beverages are diuretics, meaning that it signals for the kidneys to release more water in the form of urine. Dehydration can directly affect the skin, causing it to be dry, which contributes to an uneven complexion, dullness and even itchiness if there is less moisture.

 5 Foods to Consume

 Fatty fish (SMASH fish)

 This refers to fish high in omega-3 fatty acids, such as salmon, mackerel, anchovies, sardines and herring (SMASH fish). Omega-3 fatty acids are considered to be an essential nutrient, meaning that we cannot make them in our bodies and they need to be retrieved from an external source; often through diet. The two omega-3 fatty acids which are often referenced are eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). Western diets which are high processed carbohydrates, high saturated fat and low fiber are also higher in pro-inflammatory omega fatty acids, omega-6s [8}. For this reason, it is important to focus on consuming more omega-3 fatty acids, which are anti-inflammatory [9]. These essential fatty acids have a role in decreasing inflammatory conditions of the skin, such as eczema, acne and rosacea [8]. Additionally, they work to keep the skin well-moisturized and decrease free radical damage which can accelerate aging [8].

If you are vegetarian, there are sources of omega-3s, which are in the form of alpha-linolenic acid (ALA). ALA is eventually converted into EPA and DHA in the body, although in much smaller amounts than if you were to eat them from a fish source. Plant sources of omega-3s can be found in the highest amounts in algae, raw flaxseed oil, and other seeds like chia and hemp.

Blueberries

Blueberries, along with red grapes and cranberries are high in two plant polyphenols; resveratrol and anthocyanin. These plant compound has a variety of health benefits, including protecting cells from oxidative damage that is caused by external and internal stressors (ie. the sun, inflammatory foods) [10,11]. In addition to being a powerful antioxidant, resveratrol is also anti-inflammatory and has the ability to protect the cardiovascular system and has been implicated as an anti-carcinogenic agent. It is important to keep in mind that whole foods are better than an isolated supplement because as well as having increased bioavailability, these foods also have other nutrients such as vitamin C, which also contribute to skin health and collagen production [10].

 Avocado

Not only are avocados an excellent source of healthy fats (mostly monounsaturated), but they are filled with vitamins and minerals that are important for the whole body, including the skin [12]. Avocados are about 80% dietary fiber, which acts as a prebiotic in the digestive tract. Remember the gut-skin axis we mentioned in the introduction? Fiber acts as a prebiotic to allow good gut bacteria to thrive, which compliments the gut-skin axis, allowing skin to appear clear and healthy. This should be coupled with foods that are high in probiotics, which are fermented foods such as sauerkraut, kimchi, yogurt and kombucha. Avocados are also quite high in vitamin E, which are a powerful antioxidant and moisturizer for the skin. Similar to the other antioxidants we’ve explored, vitamin E protects from environmental damage and trauma to increase the durability and healing time of the skin and to decrease the rate of aging.

Broccoli/Broccoli sprouts

Similar to the other fruit on this list, broccoli is filled with vitamins and minerals which are sources of antioxidants. One of the most important antioxidants in broccoli, with higher concentrations in broccoli sprouts is a plant chemical compound called sulforaphane. This compound has demonstrated anti-carcinogenic and cell protective properties against a variety of cancers. Additionally, in research, sulfurophane has been tested on UV-damage from the sun, and has proven to have protective effects against this radiation which can accelerate the skin’s aging [13].

Broccoli and other members of the Brassica vegetable family contain a plant chemical called indole-3-carbinol (I3C). Not only has I3C been implicated in cancer risk protection, especially female cancers, but it supports liver function and detoxification pathways [14]. This is important for skin health, because in a lot of chronic skin conditions, there is liver congestion which usually causes hormonal metabolites to be improperly cleared and reabsorbed. This can often present as acne, eczema or psoriasis.

Green tea/Matcha

While we work on our ReLiv matcha cleanser to provide external benefits, drinking green tea or matcha, itself works from the inside out! If you are sensitive to caffeine, we suggest drinking green tea, because matcha is a much more concentrated version of green tea, meaning it is much higher in all its beneficial components such as L-theanine and epigallocatechin-3-gallate (EGCG) and including caffeine. For skin, the phytochemicals in green tea can decrease signs of aging skin by decreasing environmental damage and increasing resilience to external and internal stressors [15, 16]. EGCG is also beneficial to the skin, especially with respects to chronic inflamed skin, as it is anti-inflammatory and has anti-androgenic properties to decrease oil production which can contribute to clogged pores [16]. Moreover, it seems to have the potential to decrease bacteria growth on the skin, specifically Propionibacterium acnes, which in overgrowth can contribute to acne presentation [16].

By: Dr. Arlene Dubier ND

 References: 

1. Melnik BC. 2011. Evidence for acne-promoting effects of milk and other insulinotropic dairy products, Milk and Milk Products in Human Nutrition. 67: 131-145.
2. Grobel H & Murphy S. 2018. Acne vulgaris and acne rosacea, Integrative Medicine. Elsevier Inc. Retrieved from Clinical Key.
3. Smith R, Mann N, Braue A, Makelainen H & Varigos G. 2007. A low-glycemic-load diet improves symptoms in acne vulgaris patients: a randomized controlled trial, The American Journal of Clinical Nutrition. 86(1): 107-115. 
4. Lohwasser C, Neureiter D, Weigle B, Kirchner T & Schuppan D. 2006. The receptor for advanced glycation end products is highly expressed in the skin and upregulated by advanced glycation end products and tumor necrosis factor-alpha, Journal of Investigative Dermatology, 126(2): 291-299. 
5. Uribarri J, Woodruff S, Goodman S, Cai W, Chen X, Pyzik R, Yong A, Striker G & Vlassara H. 2013. Advanced glycation end products in food and a practical guide to their reduction in the diet, Journal of the Academy of Nutrition and Dietetics. 110(6): 911. 
6. Simon S. ND, World health organization says processed meat causes cancer, American Cancer Society. 
7. Pierard-Franchimont C, Nikkels AF, Pierard GE. 2019. Alcohol and the skin, Rev Med Liege. 74(5-6): 354-359. 
8. Balic A, Vlasic D, Zuzul K, Marinovic B & Mokos ZB. 2020. Omega-3 versus omega-6 polyunsaturated fatty acids in the prevention and treatment of inflammatory skin diseases, International Journal of Molecular Sciences. 21(3): 741. 
9. Pappas A. 2009. The relationship of diet and acne, The Journal of Dermato-Endocrinology. 1(5): 262-267. 
10. Salehi B, Prakash Mishra A et al. 2018. Resveratrol: a double-edged sword in health benefits, Biomedicines. 6(2):91. 
11. Philpott M, Cheng Lim C & Ferguson LR. 2009. Dietary protection against free radicals: a case for multiple testing to establish structure-activity relationships for antioxidant potential of anthocyanic plant species, International Journal of Molecular Sciences. 10(3): 1081-1103. 
12. Dreher ML & Davenport AJ. 2013. Hass avocado composition and potential health effects, Critical Reviews in Food Science and Nutrition. 53(7): 738-750. 
13. Sikdar S, Papadopoulou M & Dubois J. 2016. What do we know about sulforaphane protection against photoaging, Journal of Cosmetic Dermatology. 15(1).  
14. Wang SQ, Cheng LS, Liu Y, Wang JY & Jiang W. 2016. Indole-3-carbinol (I3C) and its major derivatives: their pharmacokinetics and important roles in hepatic protection, Current Drug Metabolism. 17(4): 401-409. 
15. Prasanth MI, Sivamaruthi BS, Chaiyasut C & Tencomnao T. 2019. A review of the role of green tea (Camellia sinensis) in antiphotoaging, stress resistance, neuroprotection, and autophagy, Nutrients. 11(2). 
16. Grobel H & Murphy S. 2018. Acne vulgaris and acne rosacea, Integrative Medicine, 4^th Elsevier Inc. Retrieved from Clinical Key.