CPE Monthly: Nutrition and Skin Health
By Denine Rogers, MS, RDN, LD, FAND
Today’s Dietitian
Vol. 25 No. 8 P. 48

Discovering the Connection and Evidence-Based Treatment Options for Patients

CPE Level 2

Take this course and earn 2 CEUs on our Continuing Education Learning Library

Clients often seek dietary advice from dermatologists, not dietitians, even though they frequently associate their skin diseases with the foods they eat. Dietitians know that nutrition has been shown to help alleviate certain skin disorders, but for decades other health care professionals have presumed that many common skin disorders are unrelated to diet. However, recent studies show significant evidence that diet and nutrition can affect some dermatological conditions.

Skin diseases are prevalent among Americans—and costly. The Academy of Dermatology states that skin disorders will affect 84.5 million Americans or one in four.1 Skin conditions cost the United States health care system $75 billion in medical and preventative care, including prescription and nonprescription drug costs.1

This continuing education course reviews the relationship between nutrition and skin health based on current research, discusses skin conditions for which nutrition traditionally has been an unrecognized treatment option, and focuses on how the expertise of dietitians and dermatologists are both needed for proper treatment.

The Diet and Dermatology Link
The effects diet has on skin health can be positive or negative, mainly due to the nutrients (or lack of nutrients) in food. Skin is complex and specialized, and serves multiple functions. It’s the largest organ of the body, weighing in at 8 lbs (3.6 kg) and spanning 22 square feet (2 square meters) for adults.2 Skin provides a barrier function to prevent internal water loss and protects the body from external environmental agents, including infectious organisms, chemicals, radiation, noise, and diet.3

There are three crucial skin layers: the epidermis, dermis, and hypodermis.2 The epidermis, the outermost layer, serves as a waterproof barrier and creates skin tone. The dermis beneath the epidermis contains tough connective tissue, hair follicles, and sweat glands. This layer of skin transports blood and fights infections. The hypodermis is the subcutaneous fat and deepest layer of skin. This layer of fatty tissue helps insulate the body from heat and cold and protects the body from injuries. It also provides padding to cushion internal organs, muscles, and bones.2

It’s vital that all of the skin’s functions, along with the development and replacement of these tissues, receive adequate nutrition and nutrients from birth to death. Different nutritional deficiencies of macronutrients and micronutrients can cause negative skin signs and symptoms. Macronutrients, vitamins, and essential minerals work together to maintain the skin’s barrier functions. A macronutrient and micronutrient deficiency in protein, zinc, and B vitamins can cause cheilitis, characterized by dry, scaly, and fissured lips. A deficiency in essential fatty acids can cause xerosis, described as scaly skin that can cause discomfort, itchiness, and inflammation.2

Skin Conditions and Disorders
For some skin conditions, improvements in diet and nutrition have long been considered an important treatment strategy. However, as emerging research has demonstrated, dietary changes also may play a role in treatment for a wider variety of skin diseases. What follows are four primary skin conditions and disorders for which dietary changes may be advised as one component of treatment.

Acne Vulgaris
Acne vulgaris is a chronic inflammatory skin disorder among teenagers, young adults, and some older adults that occurs when hair follicles get plugged with sebum and dead skin cells. Acne is more common in developed countries than in less industrialized regions. And in some populations, acne development is associated with the adoption of a Western diet.4

The factors that contribute to the formation of acne include the following:

• genetic predispositions;
• hormonal abnormalities (eg, androgens);
• immunological disorders; and
• psychological, environmental, and iatrogenic factors.5

Trigger Foods Associated With Acne
Researchers have hypothesized that diet may play a part in the pathogenesis of acne vulgaris, and some food products may be a trigger.5

High-Glycemic Load Diet
A high-glycemic load diet consists of high-carbohydrate foods such as refined sugars, grains, milk, and dairy products. This diet can raise blood glucose levels, cause the body to produce more insulin, and stimulate sebum production and sebaceous cell proliferation.6

Dairy Products
Dairy remains a prominent dietary component for most Western societies. The first studies on the association between dairy and acne were conducted in the 1940s. Two prospective historical studies were done in 2004 and 2008 that showed a positive correlation between acne and milk consumption, which may be due to the presence of hormones and bioactive molecules, as well as milk’s effect through the insulinlike growth factor pathway. Dairy intake may aggravate acne on several levels through these pathways, including increased oil production, inflammation, and abnormal hormonal activity.7,8

A meta-analysis of 14 observational studies evaluated the relationship between milk and dairy products and acne development. This meta-analysis found a positive relationship between dairy, whole milk, whole fat, low-fat, and skim milk consumption and acne. There was no significant relationship between yogurt and cheese and acne development. Results of the present meta-analysis recommend consuming yogurt or cheese to avoid acne creation. Further investigations are needed, especially randomized controlled trials, to confirm the effect of milk and dairy products on acne development.9

Beneficial Interventions for Acne
Other studies suggest that certain dietary interventions and micronutrient supplementation may have a positive effect on acne treatment.

Low-Glycemic Load Diet
In one study, 32 participants with mild-to-moderate acne were randomized to either a low-glycemic load diet or a high-glycemic load diet for 10 weeks.10 Those on a low-glycemic load diet demonstrated significant reductions in noninflammatory and inflammatory lesion counts, more minor sebaceous glands, decreased inflammation, and reduced acne severity grading.10

Although more studies are necessary to understand the underlying pathways of acne, incorporating low-glycemic foods may help reduce the number of visible lesions. Additional research studies are required with larger sample sizes combining a low-glycemic load diet and restricted intake of cow’s milk products.11

According to a systematic review and meta-analysis of 25 small, low-quality clinical trials that included 2,445 participants, patients with acne have decreased serum zinc levels compared with controls, suggesting that taking 137 to 300 mg of zinc sulfate or zinc gluconate twice daily by mouth can modestly improve acne compared with placebo. Participants who were treated with zinc had a significant improvement compared with those who weren’t treated with zinc, suggesting that zinc is effective for treating acne, particularly when used as monotherapy or adjunctive treatment.12

However, not all individual trials show beneficial results. In one large open-label clinical trial, 100 patients were equally randomized to receive zinc sulfate or lymecycline (tetracycline acne medication). Patients took 200 mg of zinc sulfate twice daily for 12 weeks, which was at least as effective as 300 mg lymecycline daily to reduce acne severity. Results showed that patients who received the zinc sulfate experienced modest improvements in their quality of life.13

Niacinamide, also known as nicotinamide, is one form of vitamin B3 and the amide derivative of niacin. Oral niacinamide has been studied in combination with other ingredients for the treatment of acne. In preliminary clinical research, oral niacinamide was reported to improve acne when used in combination with zinc, copper, and folic acid (marketed as Nicomide [Nic/Zn]). In an open-label, multicenter, prospective cohort study, 198 patients with acne vulgaris received 750 mg nicotinamide, 25 mg zinc, 1.5 mg copper, and 500 mcg folic acid. By week four, a relatively short treatment period, 79% of patients reported their improvement in appearance as much better compared with those who stated there was no change in their condition.14

In a multicenter, open-label, eight-week prospective study, dermatologists enrolled 235 post adolescent women with inflammatory acne vulgaris. Researchers evaluated the efficacy of adding one to four tablets of NicAzel (nicotinamide, azelaic acid, zinc, pyridoxine, copper, and folic acid) daily to patients’ current acne treatment regimen. In eight weeks, 88% of patients experienced a visible reduction in inflammatory lesions, and 81% rated their appearance as much better than at baseline. Seventy-six percent of patients thought NicAzel was at least as effective as previous treatment with oral antibiotics.15 It’s unclear whether the effects in these studies are due to niacinamide, other ingredients, or combinations.

Atopic Dermatitis (Eczema)
Affecting more than 9.6 million children and about 16.5 million adults in the United States, atopic dermatitis (AD) is the most common type of eczema.16 A chronic condition, it can come and go for years or throughout life and overlap with other eczema types. In those with AD, the immune system becomes dysfunctional and overactive, causing inflammation that damages the skin barrier, leaving the area dry and prone to itching. With darker skin tones, rashes may become purple, brown, or grayish; in lighter skin, rashes may become red.17

Research has shown that some people with eczema, especially AD, have a genetic mutation responsible for producing filaggrin, described by the National Eczema Association as a protein that helps the body maintain a healthy, protective barrier on the top layer of the skin. Without enough filaggrin to build a strong skin barrier, the moisture from our skin can escape, and bacteria, viruses, and other containments can enter. This causes many people with AD to develop very dry and infection-prone skin.17

Trigger Foods That Cause AD
Many allergenic foods interact with and sometimes cause AD. The six common allergenic foods that may trigger an AD flare include milk, eggs, wheat, soy, seafood, and nuts, and they may do so through the following three primary processes18:

1. Type 1 or immediate-type hypersensitivity, otherwise known as immunoglobulin E–mediated allergy, may trigger a flare within minutes to hours. Dietitians or allergists can screen individuals for this allergy through a skin prick or blood test, but further confirmation requires a double-blinded, placebo-controlled food challenge due to a high rate of false positive results.19

2. Late eczematous reaction, or AD flare-up, may occur 48 hours after ingesting these trigger foods. If the immunological process is unknown, a double-blinded placebo-controlled food challenge test is required.20

3. A T-cell–mediated reaction, or systemic contact dermatitis, a type of eczema, is screened via patch testing. The most common cause of systemic contact dermatitis is Balsam of Peru, a sticky aromatic liquid that comes from the bark of the Myroxolon balsamum tree native to El Salvador. It contains cinnaminic acid, vanillin, essential oils, and other compounds, and can be included in perfumes, deodorants, and cosmetics, as well as tea and coffee, food flavorings, and other products. Ingesting or coming in contact with products containing Balsam of Peru can cause an immune response in the skin, characterized by dry itchy skin, and bumps and blisters.21 Some people allergic to fragrance additives may experience a cutaneous flare after ingesting certain foods, such as tomatoes, citrus, or cinnamon.22

Beneficial Interventions for AD
Despite the complexities of AD, there are certain food products individuals can consume to treat the condition, but research shows that two in particular are likely to be more effective treatment options.

Casein Peptides
In a meta-analysis of clinical trials and intervention studies, researchers found a statistically significant 45% reduced risk of AD among infants aged 0 to 12 months who received 100% whey protein partially hydrolyzed formula compared with infants who received intact protein cow’s milk formula, based on the analysis of data from each study that most closely represented the formula intake period. In most studies, these data were available before the introduction of solid foods.23

In the prospective German Infant Nutritional Intervention study, 2,252 children for the first four months of age were randomly assigned to receive one of the following four blinded formulas as a breast milk substitute, if necessary:

• partially hydrolyzed whey formula (pHF-W);
• extensively hydrolyzed whey formula (eHF-W);
• extensively hydrolyzed casein formula (eHF-C); and
• standard cow’s milk formula.

After 10 years of follow up, the results showed a cumulative incidence of allergic diseases in high-risk children, particularly with AD, with pHF-W and eHF-C, which persisted for 10 years without rebound, whereas eHF-W showed no significant risk reduction.24

Clinical research also shows that eHF-C is equally effective as pHF-W for reducing the risk of AD in infants. This meta-analysis demonstrated that pHF-W (557 infants) vs eHF-W (559 infants) and pHF-W vs eHF-C (580 infants) were shown to be effective in the prevention of AD. For infants that can’t have breast milk exclusively, these formulas are a positive alternative based on cost-effectiveness.25

Increasing evidence suggests that children who develop AD have reduced diversity in their gut microbiota. Oral probiotics, especially certain combination products of lactobacilli species, seem beneficial for AD prevention in children, though there’s conflicting evidence on their use for treating AD. A meta-analysis of the available clinical research shows that using probiotics in conjunction with standard treatment doesn’t improve patient-rated symptoms or quality of life in adults or children with AD compared with standard therapy alone.26

However, research shows that the probiotic species Lacticaseibacillus paracasei, Lacticaseibacillus rhamnosus, and Lactiplantibacillus plantarum are promising treatments. In a double-blinded, randomized, placebo-controlled clinical trial, researchers enrolled 60 patients aged between 6 months and 19 years with mild, moderate, or severe AD. Of the 60 patients, 40 completed the study, and there were 24 probiotic interventions and 16 placebo. After treatment for six months, children and adolescents with AD in the probiotics group experienced a significant clinical response to a mixture of Lactobacillus rhamnosus, Lactobacillus acidophilus, Lactobacillus paracasei, and Bifidobacterium lactis.27

Fermented Milk
In a clinical research study, 415 pregnant women from 36 weeks gestation to three months postpartum randomly received fermented milk or placebo milk. Patients who drank 250 mL of fermented milk containing Lactobacillus rhamnosus GG, Lactobacillus acidophilus, and Bifidobacterium animalis reduced their child’s risk of developing AD by age 6 by approximately 52% compared with placebo milk.28

Galacto-oligosaccharides in syrup or formula, along with probiotics or fructooligosaccharides, may reduce the risk of AD development in infants at risk of atopy, an exaggerated IgE-mediated immune response that stems from a genetic tendency to develop allergic diseases such as allergic rhinitis, asthma, and AD. In a prospective, double-blinded, placebo-controlled study, healthy term infants at risk of atopy were fed either a prebiotic-supplemented or placebo-supplemented hypoallergenic formula during the first six months of life. Following this intervention period, follow-up continued until age 5.

Ninety-two children (50 in the placebo group and 42 in the intervention group) completed the follow-up. The five-year cumulative incidences of allergic manifestation and AD were significantly lower in the prebiotic-supplemented group than in the placebo group. When started early in life, oligosaccharide prebiotics have a protective effect against allergic manifestations in high-risk infants.29

One study, however, had opposite results. Two hundred twenty-six healthy, formula-fed, term infants were randomly assigned to one of three study formula groups. The groups consisted of a control group, a PG4 group (ie, control formula supplemented with 4 g/L of a prebiotic blend containing polydextrose [PDX] and galacto-oligosaccharides [GOS]), and a PGL8 group (ie, control formula supplemented with 8 g/L of a prebiotic blend containing PDX, GOS, and lactulose). The results showed that the formula containing 4 g/L of PDX and GOS (1:1 ratio) given as often as necessary for approximately four months increased the potential of developing AD as an adverse effect up to 11% compared with a control formula.30

Psoriasis is an inflammatory, chronic skin disease that significantly affects patients’ quality of life. It’s a condition in which skin cells build up and form scales and itchy, dry patches. The cause of psoriasis is unknown, but there are several reasons why it may develop. Psoriasis is a T-cell–mediated autoimmune dermatological disorder and is considered a multifactorial disabling condition caused by the interaction between genetic and environmental triggers. Environmental factors such as emotional stress and smoking can negatively influence the onset of symptoms and disease severity. One of the most critical environmental factors for patients with psoriasis is diet. Improper nutrition, poor weight status, and metabolic diseases may increase clinical symptoms or even trigger the disease process.31

Recent studies have suggested that when there’s better control of psoriasis inflammation, the risk of CVD, stroke, metabolic syndrome, and other diseases associated with inflammation decreases.32

Trigger Foods That Cause Psoriasis

One trigger that may cause psoriasis in some patients is gluten-containing foods. Clinicians should test patients who have gastrointestinal symptoms for immunoglobulin A antibodies to determine whether they have celiac disease.33 Testing patients for immunoglobulin A antibodies is vital since they’re produced in the small intestine where gluten causes inflammation and irritation in those who are sensitive.34

Research studies suggest psoriasis and celiac disease share common genetics and inflammatory pathways. One large study found that 25,341 patients with psoriasis had a 2.2-fold risk of being diagnosed with celiac disease compared with matched controls.35

Another study, however, found no association between gluten intake and new onset of psoriasis. This cohort study of 85,185 women in the psoriasis analysis arm of the study used food frequency questionnaires to calculate the gluten content in their diets every four years. The results showed that increased gluten intake wasn’t associated with any outcomes.36

Obesity is likely a predisposition to psoriasis and is suggested as one of the main factors of chronic inflammatory processes associated with psoriasis.37 A large population-based Norwegian study, including approximately 35,000 subjects, showed an association between metabolic syndrome and increased risk of psoriasis. The analysis of metabolic factors suggested that this positive association could have been attributed to adiposity.38 A poor diet that provides a significant number of high-calorie foods and is low in nutritional quality has contributed to increased body weight and metabolic diseases, increasing psoriatic inflammation.

Beneficial Interventions for Psoriasis

Low-Calorie Diet and Mediterranean Diet
Studies suggest that preventing weight gain, managing average body weight, and reducing body mass may lower the incidence of psoriasis.39

One study showed 37 adult patients who were overweight or obese and never treated with drugs for stable chronic plaque psoriasis were placed on a 10-week, two-phase weight loss program consisting of a four-week protein-sparing, very-low-calorie ketogenic diet, and a six-week balanced, low-calorie Mediterranean-style diet. The results showed that adult patients on the low-calorie Mediterranean diet had a significant reduction in the body surface area and an improvement in itch severity. This demonstrated that dietary intervention is an effective first-line strategy to reduce psoriasis severity.

Bodyweight reduction through a low-calorie diet may help decrease visceral fatty tissue while increasing ketone bodies and diminishing the inflammatory response linked to psoriasis and obesity.40

Gluten-Free Diets
A gluten-free diet may improve psoriasis in individuals with gluten sensitivity or celiac disease. An open-label research study included 30 individuals with psoriasis and elevated immunoglobulin A antibodies to gliadin. Researchers started participants on a gluten-free diet for three months, followed by a regular diet for three months. After a three-month gluten-free diet, the mean Psoriasis Area and Severity Index score in all 30 participants improved. All participants were allowed to continue with their topical or systemic psoriasis treatment. After discontinuing the gluten-free diet and initiating the regular diet, 18 subjects began systemic or local therapy for worsening psoriasis.41

Vitamin D
Vitamin D supplementation is a promising treatment for psoriasis. Calcitriol, the naturally occurring active form of vitamin D3 (cholecalciferol), has long been used for topical psoriasis therapy. In two randomized, double-blinded clinical trials, twice-daily application of calcitriol ointment for eight weeks resulted in clearing or minimal residual psoriasis in approximately 34% of patients, compared with 12% to 22.5% of patients treated with placebo. Calcitriol ointment is an effective, safe, and well-tolerated topical psoriasis therapy.42

But while the calcitriol topical treatment is well established and represents an effective and safe treatment option with or without topical steroids, the beneficial effects of vitamin D oral supplementation in general don’t seem to prevent or improve psoriasis symptoms. The findings of a clinical study of 65 older adults with mild psoriasis show that taking 200,000 IU of oral vitamin D3 followed by 100,000 IU of vitamin D3 monthly for one year doesn’t affect the severity or spread of psoriasis when compared with placebo.43

Rosacea is a common chronic inflammatory skin condition that primarily affects the face with flushing and redness. The redness from rosacea becomes ruddier and more persistent over time. There’s no cure, and its causes are unknown. If left untreated, inflammatory bumps and pimples often develop. The individuals at greatest risk have fair skin and tend to flush or blush easily.44

Trigger Foods That Cause Rosacea
Many triggers may exacerbate rosacea symptoms, including hot temperatures, sun exposure, spicy foods, alcohol consumption, exercise, and feelings of anger or embarrassment.45 A survey from the National Rosacea Society about dietary triggers patients frequently cited found that, of more than 400 patients, 78% had altered their diet due to rosacea flare-ups. Within this group, 95% reported a consecutive reduction in flares.46 Patients within this group break down the food and beverage triggers into heat, alcohol, capsaicin, and cinnamaldehyde related.45 Categorically, hot beverages acted as a trigger: 33% described hot coffee as a trigger, while 30% named hot tea as a trigger. Alcohol was another frequent cause, with 52% identifying wine as a trigger and 42% identifying hard liquor as such. Capsaicin is found in certain spices and peppers. Three-quarters of respondents reported spices as a cause, including hot sauce (54%), cayenne pepper (47%), and red pepper (37%). Foods containing cinnamaldehyde also were mentioned as frequent triggers, such as tomatoes (30%), chocolate (23%), and citrus (22%).45,47

In addition to food triggers, research shows there’s a possible role of a gut-to-skin connection in rosacea. A population-based cohort study of approximately 50,000 Danish patients with rosacea found that the prevalence of celiac disease, Crohn’s disease, ulcerative colitis, Helicobacter pylori infection, small intestinal bacterial overgrowth, and irritable bowel syndrome was greater overall among those with rosacea compared with controls.48 There’s a lack of clinical trial research about the possible treatment of rosacea with probiotics and the microbiome; therefore, more research is necessary to further understand this gut-to-skin connection.

Beneficial Interventions for Rosacea
The only promising research for treating rosacea has focused on the use of topical 90% medical-grade kanuka honey and 10% glycerine (Honevo). A clinical research study of 138 adults shows that applying Honevo twice daily for eight weeks to the affected areas and washing it off after 30 to 60 minutes is more effective than Cetomacrogol cream, an emollient, for improving rosacea symptoms. Roughly twice as many patients responded to Honevo compared with Cetomacrogol cream.49

Putting It Into Practice
Dermatologists can make referrals to dietitians who can provide evidence-based dietary strategies to address patients’ skin conditions. To work together, dietitians and dermatologists must take a multidisciplinary approach to comprehensively evaluate triggers and responses to treatment, address confounding factors, such as dietary and nutrition habits, and educate patients and families. Currently, three programs across the country take a multidisciplinary approach to treat AD, and the clinicians involved have reported excellent results.50-52 Multidisciplinary teams that can assist dermatologists’ critical role in educating and treating patients for their skin diseases and disorders can include not only dietitians but also nurse practitioners, psychotherapists and psychologists, social workers, rehabilitation therapists, and allergy-immunology fellows in training.

Dietitians can work with dermatologists in a team effort to help treat patients’ skin disorders in the following five ways:

1. Focus on the dermatologist’s evaluation of the patient when making initial recommendations. RDs also can offer patients educational resources to help prevent them from relying on those less reliable.

2. Team up with dermatologists to encourage patients to reduce the risk of eating allergenic foods and using products with allergenic ingredients associated with their skin disease by adopting a more nutritious diet in tandem with medical interventions.

3. Develop and provide customized care plans in writing to meet patients’ and their families’ needs. Prepare to review and modify these care plans at follow-up visits as the disease state changes, since patients and caregivers may forget or misunderstand skin care recommendations without written step-by-step instructions.

4. Teach the same fundamental concepts and reinforce the same messages the dermatologist delivers to patients and caregivers. Dermatologists and dietitians can provide one-on-one communication with patients and written nutrition and skin health home care action plans. In addition, dietitians and dermatologists together can hold group discussions and teach in classroom settings to educate patients about nutrition and skin health.

5. Recommend patients and caregivers review advice they receive from friends, family members, and other sources with their dietitian and dermatologist. Making even minor changes to their treatment regimen can be detrimental, lack benefit, and add unnecessary costs. Maintaining an open and ongoing dialog with patients, caregivers, and their clinicians may improve adherence to treatment plans and health outcomes.

Dietitians and dermatologists should meet with one another to discuss each patient’s current and future care plan and resolve any issues. These meetings can prevent miscommunication and ensure patients receive the same information and consistent messages regarding their treatment plan. The ultimate goal of multidisciplinary care is to give patients, families, and caregivers the skills and tools they need to relieve symptoms at home and improve their quality of life.

— Denine Rogers, MS, RDN, LD, FAND, is an integrative and functional dietitian and owner of Living Healthy Skincare (www.livinghealthyskincare.com).


Learning Objectives
After completing this continuing education course, nutrition professionals should be better able to:
1. Distinguish the foods, dietary patterns, and lifestyles that can positively and negatively affect skin health.
2. Examine nutrition’s effect on skin disorders such as eczema, acne, psoriasis, and rosacea.
3. Counsel clients on how to implement nutrition and lifestyle changes that help manage skin diseases.
4. Demonstrate how dietitians and dermatologists can work together to improve their clients’ skin health.


1. Which of the three crucial skin layers brings blood to the skin and fights against infection?
a. Hyperdermis
b. Epidermis
c. Dermis
d. Hypodermis

2. Which of the following isn’t a causal factor that contributes to acne formation?
a. Immunological disorders
b. Hormonal abnormalities
c. Genetic predispositions
d. Lifestyle conditions

3. What’s an effective treatment option beneficial for patients who have atopic dermatitis (AD)?
a. Low-glycemic load diet
b. Probiotics
c. Vitamin D
d. Kanuka honey

4. Balsam of Peru is the most common cause of which skin disorder?
a. Acne vulgaris
b. AD
c. Psoriasis
d. Rosacea

5. Which of the following does the National Eczema Association describe as a protein that helps the body maintain a healthy, protective barrier on the top layer of skin?
a. Filaggrin
b. Pustules
c. Papules
d. Carbuncle

6. What’s the most critical environmental factor that impacts patients with psoriasis?
a. Emotional stress
b. Smoking
c. Diet
d. Genetics

7. Which trigger food doesn’t exacerbate rosacea symptoms?
a. Wine
b. Chocolate
c. Hot sauce
d. Milk

8. In what ways can dietitians and dermatologists take a multidisciplinary approach to treating patients’ skin diseases?
a. Develop and provide customized written care plans to meet the individual patient’s and family’s needs.
b. Encourage patients and caregivers to consider following advice from friends, family members, and other sources for alternative treatments.
c. Discourage patients from taking responsibility for eating allergenic foods and using products with allergenic ingredients associated with their skin disease.
d. Suggest dermatologists offer patients diet and nutrition recommendations.

9. Which dietary intervention shows a positive effect on acne treatment?
a. Vitamin D
b. Low-calorie diet
c. Low-glycemic load
d. Fermented milk

10. The Mediterranean diet is a beneficial treatment option for which of the following skin disorders?
a. Acne vulgaris
b. Rosacea
c. AD
d. Psoriasis


1. Lim HW, Collins SAB, Resneck JS Jr, et al. The burden of skin disease in the United States. J Am Acad Dermatol. 2017;76(5):958-972.

2. Noland D, Drisko JA, Wagner L, eds. Integrative and Functional Medical Nutrition Therapy: Principles and Practices. Springer Nature; 2020.

3. Shah R. Environmental agents which lead to health problems. Biology Discussion website. https://www.biologydiscussion.com/environment/environmental-agents-which-lead-to-health-problems/16781. Accessed September 9, 2022.

4. Baldwin H, Tan J. Effects of diet on acne and its response to treatment. Am J Clin Dermatol. 2021;22(1):55-65.

5. Kucharska A, Szmurło A, Sińska B. Significance of diet in treated and untreated acne vulgaris. Postepy Dermatol Alergol. 2016;33(2):81-86.

6. Smith RN, Mann NJ, Braue A, Mäkeläinen H, Varigos GA. A low-glycemic-load diet improves symptoms in acne vulgaris patients: a randomized controlled trial. Am J Clin Nutr. 2007;86(1):107-115.

7. Adebamowo CA, Spiegelman D, Berkey CS, et al. Milk consumption and acne in teenaged boys. J Am Acad Dermatol. 2008;58(5):787-793.

8. Adebamowo CA, Spiegelman D, Danby FW, Frazier AL, Willett WC, Holmes MD. High school dietary dairy intake and teenage acne. J Am Acad Dermatol. 2005;52(2):207-214.

9. Aghasi M, Golzarand M, Shab-Bidar S, Aminianfar A, Omidian M, Taheri F. Dairy intake and acne development: a meta-analysis of observational studies. Clin Nutr. 2019;38(3):1067-1075.

10. Kwon HH, Yoon JY, Hong JS, Jung JY, Park MS, Suh DH. Clinical and histological effect of a low glycaemic load diet in treatment of acne vulgaris in Korean patients: a randomized, controlled trial. Acta Derm Venereol. 2012;92(3):241-246.

11. Dréno B, Bettoli V, Araviiskaia E, Sanchez Viera M, Bouloc A. The influence of exposome on acne. J Eur Acad Dermatol Venereol. 2018;32(5):812-819.

12. Yee BE, Richards P, Sui JY, Marsch AF. Serum zinc levels and efficacy of zinc treatment in acne vulgaris: a systematic review and meta‐analysis. Dermatol Ther. 2020;33(6):e14252.

13. Tolino E, Skroza N, Mambrin A, et al. An open-label study comparing oral zinc to lymecycline in the treatment of acne vulgaris. J Clin Aesthet Dermatol. 2021;14(5):56-58.

14. Niren NM, Torok HM. The Nicomide Improvement in Clinical Outcomes Study (NICOS): results of an 8-week trial. Cutis. 2006;77(1 Suppl):17-28.

15. Shalita AR, Falcon R, Olansky A, et al. Inflammatory acne management with a novel prescription dietary supplement. J Drugs Dermatol. 2012;11(12):1428-1433.

16. Silverberg JI, Simpson EL. Association between severe eczema in children and multiple comorbid conditions and increased healthcare utilization. Pediatr Allergy Immunol. 2013;24(5):476-486.

17. Atopic dermatitis. National Eczema Association website. https://nationaleczema.org/Eczema/types-of-Eczema/atopic-dermatitis

18. Katta R, Kramer MJ. Skin and diet: an update on the role of dietary change as a treatment strategy for skin disease. Skin Therapy Lett. 2018;23(1):1-5.

19. Katta R, Desai SP. Diet and dermatology: the role of dietary intervention in skin disease. J Clinical Aesthet Dermatol. 2014;7(7):46-51.

20. Purba MB, Kouris-Blazos A, Wattanapenpaiboon N, et al. Skin wrinkling: can food make a difference? J Am Coll Nutr. 2001;20(1):71-80.

21. Ngan V. Balsam of Peru allergy. DermNet website. https://dermnetnz.org/topics/balsam-of-peru-allergy. Updated April 2023.

22. Cosgrove MC, Franco OH, Granger SP, Murray PG, Mayes AE. Dietary nutrient intakes and skin-aging appearance among middle-aged American women. Am J Clin Nutr. 2007;86(4):1225-1231.

23. Alexander DD, Cabana MD. Partially hydrolyzed 100% whey protein infant formula and reduced risk of atopic dermatitis: a meta-analysis. J Pediatr Gastroenterol Nutr. 2010;50(4):422-430.

24. von Berg A, Filipiak-Pittroff B, Krämer U, et al. Allergies in high-risk schoolchildren after early intervention with cow's milk protein hydrolysates: 10-year results from the German Infant Nutritional Intervention (GINI) study. J Allergy Clin Immunol. 2013;131(6):1565-1573.

25. Iskedjian M, Szajewska H, Spieldenner J, Farah B, Berbari J. Meta-analysis of a partially hydrolysed 100%-whey infant formula vs. extensively hydrolysed infant formulas in the prevention of atopic dermatitis. Curr Med Res Opin. 2010;26(11):2599-2606.

26. Makrgeorgou A, Leonardi‐Bee JO, Bath‐Hextall FJ, et al. Probiotics for treating eczema. Cochrane Database Syst Rev. 2018;11(11):CD006135.

27. de Andrade PDSMA, Maria E Silva J, Carregaro V, et al. Efficacy of probiotics in children and adolescents with atopic dermatitis: a randomized, double-blind, placebo-controlled study. Front Nutr. 2022;8:833666.

28. Simpson MR, Dotterud CK, Storrø O, Johnsen R, Øien T. Perinatal probiotic supplementation in the prevention of allergy related disease: 6 year follow up of a randomised controlled trial. BMC Dermatol. 2015;15:13.

29.Arslanoglu S, Moro GE, Boehm G, Wienz F, Stahl B, Bertino E. Early neutral prebiotic oligosaccharide supplementation reduces the incidence of some allergic manifestations in the first 5 years of life. J Biol Regul Homeost Agents. 2012;26(3 Suppl):49-59.

30. Ziegler E, Vanderhoof JA, Petschow B, et al. Term infants fed formula supplemented with selected blends of prebiotics grow normally and have soft stools similar to those reported for breast-fed infants. J Pediatr Gastroenterol Nutr. 2007;44(3):359-364.

31. Zuccotti E, Oliveri M, Girometta C, et al. Nutritional strategies for psoriasis: current scientific evidence in clinical trials. Eur Rev Med Pharmacol Sci. 2018;22(23):8537-8551.

32. Takahashi H, Iizuka H. Psoriasis and metabolic syndrome. J Dermatol. 2012;39(3):212-218.

33. Svoboda SA, Christopher M, Shields BE. Reexamining the role of diet in dermatology. Cutis. 2021;107(6):308-314.

34. Benson BC, Mulder CJ, Laczek JT. Anti-gliadin antibodies identify celiac patients overlooked by tissue transglutaminase antibodies. Hawaii J Med Public Health. 2013;72(9 Suppl 4):14-17.

35. Bhatia BK, Millsop JW, Debbaneh M, Koo J, Linos E, Liao W. Diet and psoriasis, part II: celiac disease and role of a gluten-free diet. J Am Acad Dermatol. 2014;71(2):350-358.

36. Drucker AM, Qureshi AA, Thompson JM, Li T, Cho E. Gluten intake and risk of psoriasis, psoriatic arthritis, and atopic dermatitis among United States women. J Am Acad Dermatol. 2020;82(3):661-665.

37. Barros G, Duran P, Vera I, Bermúdez V. Exploring the links between obesity and psoriasis: a comprehensive review. Int J Mol Sci. 2022;23(14):7499.

38. Snekvik I, Nilsen TIL, Romundstad PR, Saunes M. Metabolic syndrome and risk of incident psoriasis: prospective data from the HUNT Study, Norway. Br J Dermatol. 2019;180(1):94-99.

39. Alotaibi HA. Effects of weight loss on psoriasis: a review of clinical trials. Cureus. 2018;10(10):e3491.

40. Castaldo G, Rastrelli L, Galdo G, Molettieri P, Aufiero FR, Cereda E. Aggressive weight-loss program with a ketogenic induction phase for the treatment of chronic plaque psoriasis: a proof-of-concept, single-arm, open-label clinical trial. Nutrition. 2020;74:110757.

41. Pona A, Haidari W, Kolli SS, Feldman SR. Diet and psoriasis. Dermatol Online J. 2019;25(2):13030/qt1p37435s.

42. Kircik L. Efficacy and safety of topical calcitriol 3 microg/g ointment, a new topical therapy for chronic plaque psoriasis. J Drugs Dermatol. 2009;8(8 Suppl):s9-16.

43. Jarrett P, Camargo CA Jr, Coomarasamy C, Scragg R. A randomized, double-blind, placebo-controlled trial of the effect of monthly vitamin D supplementation in mild psoriasis. J Dermatolog Treat. 2018;29(4):324-328.

44. Gürtler A, Laurenz S. The impact of clinical nutrition on inflammatory skin diseases. J Dtsch Dermatol Ges. 2022;20(2):185-202.

45. Weiss E, Katta R. Diet and rosacea: the role of dietary change in the management of rosacea. Dermatol Pract Concept. 2017;7(4):31-37.

46. National Rosacea Society. Hot sauce, wine and tomatoes cause flare-ups, survey finds. Rosacea Review. Fall 2005. https://www.rosacea.org/rosacea-review/2005/fall/hot-sauce-wine-and-tomatoes-cause-flare-ups-survey-finds
7. Scheman A, Rakowski EM, Chou V, Chhatriwala A, Ross J, Jacob SE. Balsam of Peru: past and future. Dermatitis. 2013;24(4):153-160.

48. Egeberg A, Weinstock LB, Thyssen EP, Gislason GH, Thyssen JP. Rosacea and gastrointestinal disorders: a population‐based cohort study. Br J Dermatol. 2017;176(1):100-106.

49. Braithwaite I, Hunt A, Riley J, et al. Randomised controlled trial of topical kanuka honey for the treatment of rosacea. BMJ Open. 2015;5(6):e007651.

50. Grossman SK, Schut C, Kupfer J, Valdes-Rodriguez R, Gieler U, Yosipovitch G. Experiences with the first eczema school in the United States. Clin Dermatol. 2018;36(5):662-667.

51. Gieler U, Schmid-Ott G. Atopic eczema school — a new and successful patient management program. Dermatology and Psychosomatics/Dermatologie und Psychosomatik. 2004;5(3):114-116.

52. Boguniewicz M, Nicol N, Kelsay K, Leung DYM. A multidisciplinary approach to evaluation and treatment of atopic dermatitis. Semin Cutan Med Surg. 2008;27(2):115-127.