It’s almost inevitable as a female that at some point in your life you will encounter challenges with your skin, hair, dental, nail health. The beauty industry has capitalized on this unfortunate outcome by promoting products that claim to hydrate and clear skin, promote hair and nail growth, whiten and strengthen teeth; but the reality is these products may provide temporary satisfaction but inevitably will leave you searching for the next new product once symptoms re-emerge. While products may have benefits for some, we can’t ignore the underlying cause of our undesirable symptoms: our nutrition status.
THE SKIN-GUT AXIS
The skin is the largest organ in the body, its primary function is to serve as a defense mechanism and boundary between your external and internal environments. In doing so, it hosts diverse bacterial communities in its multiple layers in order to protect and provide antimicrobial effects . When this community of bacteria becomes disturbed or nutrient deficiencies are present, which impairs the structural foundation of skin layers, unwanted symptoms begin to emerge. Skin health is one of the most common reasons women seek products to help their dry skin, scarring, acne, psoriasis, rosacea, atopic dermatitis and so forth. The skin-gut axis, the connection between the gut microbiome (or bacteria communities in the gut) and the microbial (bacterial) communities on the skin, has been able to provide a strong explanation for the emergence of many unwanted skin problems .
Like the skin, the gut also serves as a barrier between your internal and external environments to protect the body from pathogens, viruses and other foreign invaders; preventing them from escaping through the intestinal lining and creating inflammation throughout the body. The gut and the skin are connected via their unique features to contain a substantial amount of immune cells and hosting of these bacterial communities [1,2]. When the lining of the gut is impaired, or ‘leaky’, pathogens seep through and initiate an inflammatory response which manifests as inflammation on the skin as well. A dysbiosis in the gut microbiome, or the presence of more ‘bad’ than ‘good’ bacteria, along with the triggering of the inflammatory response from the gut has been linked to a variety of skin conditions such as acne, atopic dermatitis, eczema, allergies, rosacea and other skin diseases . Figure 1 displays a picture of how pathogens that present in the gut manifest themselves on the skin surface . Breaking it down even further, all of these ‘good’ and ‘bad’ bacteria actually have names to coincide. For example, when a bacteria called Lactobacillus paracasei is present, it helps reduce inflammation and the size of acne lesions . Conversely, when a bacteria called Faecalibacterium prausnitzii is present or abundant it contributes to chronic, progressive atopic dermatitis . These are complex names you will never have to remember but are only used to portray the impact specific bacteria can have on your skin health. The bacteria present in your gut is dependent on a myriad of factors: your mother’s gut microbiome, whether you were breastfed or formula fed, genetics, nutrition, exposure to viruses and lifestyle factors. Consumption of more refined, hydrogenated oils such as canola, sunflower and vegetable oils, lead to more inflammation and proliferation of ‘bad’ bacteria which manifests on the skin . Additionally, low intake of fiber and complex carbohydrates interferes with the production of postbiotics and the integrity of the intestinal wall to prevent infiltration of pathogens and other ‘bad’ bacterias .
While the gut has been shown to have a significant impact on overall skin health, the overall nutrition status of an individual plays an equally important role. The physical structure of the skin layers are composed of proteins and nutrients. The skin contains proteins that aid as a barrier, wound healing, UV protection and stability [1,2]. The antimicrobial barrier of the skin helps to prevent growth of pathogens and bacteria containing antioxidants such as Vitamin C to aid in its effects; while the permeability barrier is composed of fatty acids, cholesterol and ceramide [2,3]. Deficiencies in Vitamin A, Zinc and Vitamin D have been shown in atopic dermatitis, Selenium deficiencies has been associated with psoriasis, low Zinc and Vitamin C associated with acne, and Vitamin E deficiencies in changes with skin collagen elasticity . Of course, please do not begin supplementing these minerals based on your given condition as there are often multiple pieces to the puzzle and supplementation of one mineral can often lead to deficiencies in another.
HAIR HEALTH + MICRONUTRIENTS
Hair loss is frequently seen in women with a diagnosis of hypothyroidism but can occur even in women without thyroid complications. Hair follicles rapidly divide and have a high turnover rate involving replication of their DNA which requires an adequate supply of nutrients and energy [3,4]. When the body is lacking adequate nutrition, hair growth and regeneration is going to take the backseat over other essential bodily functions. Iron is a vital step in DNA synthesis and therefore hair growth. Hair loss is often reported as a common symptom in individuals with iron deficiency as commonly seen with Celiac disease, excessive menstrual bleeding or individuals who take antacids . Individuals who abide by a vegetarian or vegan diet often see hair loss as a result of zinc deficiency as the bioavailability of zinc is lower in vegetables than in animal proteins . Additionally, frequent intake of legumes and whole grains, as common but not always seen in vegetarian diets, bind to zinc and inhibit its absorption . Other nutrients such as niacin, vitamin A and selenium have also been tied to hair loss . Interestingly, selenium deficiencies have also been found in individuals with hypothyroidism however the connection between whether selenium deficiency is the cause for hair loss in hypothyroidism has not been clearly identified. Many hair growth products promote these nutrients in their products for reduction in hair loss: Vitamin A, selenium and Vitamin E. However, toxicity from these nutrients caused by improper supplement usage, most notably vitamin A and selenium, have actually been shown to cause increased generalized hair loss rather than improving hair growth . Deficiencies in these nutrients don’t always result in obvious clinical symptoms; before obvious symptoms occur, deficiencies can still have a biological impact. So while you may not have the obvious Vitamin A deficiency symptoms as defined by Google: vision disturbances, dry skin, delayed growth and infertility, inadequate levels for your individual needs could still be impacting your hair growth and other bodily functions at the cellular level .
DENTAL HEALTH + NUTRITION
As with skin, hair and nails, your teeth are literally composed of minerals and poor dental health (frequent cavities, bleeding gums, root canals) should be a big, red flag for nutrient imbalances. Teeth are physically made from minerals and, of course, the obvious enemy of teeth structure which we frequently hear about are sugars because sugars can literally demineralize your teeth . But further nutrients such as Vitamin D and calcium cause low mineralization of teeth, Vitamin A deficiency impacts tooth formation, and Vitamin C deficiencies leads to delayed wound healing and bleeding gums .
While we can continue to list each individual micronutrient and its significant role in the health of teeth, skin and hair we can’t avoid the role stress has in mineral depletion as well. Having deficiencies in these nutrients does not necessarily mean you are not consuming enough foods with these nutrients in them, although it could. But it could also mean your gut health is impaired or has been exposed to viruses that are creating inflammation, leakage of your gut and inhibiting absorption of these essential nutrients. Other stressors on your body, which can look vastly different for each individual, can use a significant amount of resources and energy to maintain that ‘fight-or-flight’ state and work hard to bring your body back to balance. Assessing your dietary intake of these nutrients is only one piece of the puzzle, addressing other areas of your life which may be stealing these essential nutrients from promoting healthy skin, hair, teeth and nails is another imperative piece that should not be overlooked.
1. Mahmud MR, Akter S, Tamanna SK, et al., Impact of gut microbiome on skin health: gut-skin axis observed through the lenses of therapeutics and skin diseases. Gut Microbes. 2022 Jan-Dec;14(1):2096995. doi: 10.1080/19490976.2022.2096995.
2. Park K. Role of micronutrients in skin health and function. Biomol Ther (Seoul). 2015 May;23(3):207-17. doi: 10.4062/biomolther.2015.003. Epub 2015 May 1.
3. Andreas M. Finner, Nutrition and Hair: Deficiencies and Supplements, Dermatologic Clinics, 1. 2013. https://doi.org/10.1016/j.det.2012.08.015.
4. Guo EL, Katta R. Diet and hair loss: effects of nutrient deficiency and supplement use. Dermatol Pract Concept. 2017 Jan 31;7(1):1-10. doi: 10.5826/dpc.0701a01.
6. Streit, L. (2018, June 2). 8 signs and symptoms of vitamin A deficiency. Healthline. Retrieved December 9, 2022, from https://www.healthline.com/nutrition/vitamin-a-deficiency-symptoms#TOC_TITLE_HDR_5
7. Tungare S, Paranjpe AG. Diet and Nutrition To Prevent Dental Problems. [Updated 2022 Sep 9]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2022 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK534248/