1. Introduction

Acne is the most common disease of the skin that affects individuals in all ages [1, 2]. Diet was reported the third most frequently implicated factor (after hormones and genetics) [3-5] in the development of acne [6]. The relationship between diet & acne was highly controversial [7, 8]. Dermatologists revisited the potential link between diet & skin [5, 9-12].

Many acne patients believed that their acne was exacerbated by certain diets i.e. nuts, chocolate & fatty foods [3]. Low incidence of acne was found in non-Western culture eating traditional low milk diets [12, 13]. A low glycemic load (LGL) diet improved symptoms and insulin sensitivity in acne patients [14]. Convincing data exist supporting the role of dairy products and high-glycemic index (GI) food in influencing hormonal factors, which can increase acne prevalence and severity [15]. The prevelance of acne is lower in rural, non-industrial societies i.e. Eskimo population than in modern Western population [16, 17].

The present study is the first in Upper Egypt to investigate the type of nutrition and its effect on acne severity among acne patients using a validated food frequency questionnaire. The study aimed to illustrate profile of acne & its relation to diet and to recommend a validated dietary regimen for acne patients as well.

2. Methods

A prospective case-control study was conducted at Assiut and Student University Hospitals, Assiut, Egypt. A total of 460 subjects of both sexes were included in the study from October 2011 to October 2013. The study included 230 patients with acne vulgaris, 145 (< 20 years old) & 85 (20-30 years old) who attended the dermatology outpatient clinic and 230 similar socio-demographically cross-matched healthy volunteers were included as controls, 180 (< 20 years old) & 50 (20-30 years old). They did not have any skin or systemic disease, they attended the dermatology outpatient clinic with their diseased relatives or friends. Exclusion criteria include: patients with juvenile acne vulgaris (<14 years old), those with other skin or systemic disease. Through clinical examination were performed by a single dermatologist. Informed consent was obtained from all patients and controls. The Medical Ethics Committee of the Faculty of Medicine, Assiut University approved the study protocol.

Acne severity in patients were classified as mild, moderate & severe according to the classification of the American Academy of Dermatology [18].

− Mild acne: characterized by the presence of few papules and pustules mixed with comedones, but no nodules.

− Moderate acne: characterized by the presence of many papules and pustules together with a few nodules.

− Severe acne: characterized by the presence of numerous papules and pustules, as well as many nodules.

Moreover the clinical diagnosis of severe acne was based on the presence of any of the following criteria:

1. Persistent or recurrent inflammatory nodules.

2. Extensive papulopustular lesions

3. Ongoing scarring.

4. Persistent purulent and /or serosanguinous discharge.

5. Sinus tubes.

Two formulated tools were used in the study:

First tool: Interviewing questionnaires that included two parts:

1- Sociodemographic data including (age, sex, residence, level of education, family income, occupation and family history of acne). Anthropometric measurements including weight, height, and body mass index (BMI) were taken.

2- Questions related to food habits, drug intake and diet history.

Second tool: A recommended diet regime set up by the author was given [19].

- Content validity of the questionnaires sheet was checked by expert Professors in the field of medicine dietetion and nursing and corrections were carried out accordingly.

- Pilot study performed on 5 patients to test applicability of the research, estimate time needed for data collection to verify formulated tools of the necessary modifications.

- The purpose and nature of the study were explained to participants.

- Statistical analyses: Data was statistically analyzed using SPSS Program Version 9.X² and Chi-Square distribution test Version 16 was used to test the significance. Association was considered statistically significant when P-value was less than 0.05 [20].

3. Results

3.1. Sociodemographic Factors and Acne

The 230 acne patients included 97 mild, 112 moderate and 21 severe acne. The patient group (230) consisted of 199 females (86.5%) and 31 males (13.5%). Of the 230 controls, 182 (79.1%) were females and 48 (20.9%) were males (Table 1).

In the patient group, 145 (63.0%) were (< 20 years old) and 85 (37.0%) were (20- <30 years old). In controls, 180 (78.3%) were (< 20 years old ) and 58 (21.7%) were (20- <30 years old). Acne was significantly higher in females (p< 0.001) & in young patients (p< 0.05). The prevalence of acne was insignificantly lower in both industrial and non-industrial societies than in urban and rural ones. Table 1 revealed that prevalence of acne was significantly higher among patients with high education 77.8% (p< 0.05) & medium family income 40.4% (p< 0.001). Positive family history of acne was significantly high in patients (67.0%) compared to controls (p< 0.001).

Table 1. Sociodemographic factors and family history in acne patients and controls in Upper Egypt

Anthropometric measurements and acne is given in Table 2. The mean weights of acne patients and control subjects were 60.03±9.40 kg; and 57.47±8.36 kg; respectively. While, the mean lengths of acne patients and controls were 161.45±7.50cm and 158.31±7.27cm; respectively. The study revealed significant differences between acne patients and controls for weight (p < 0.05) and length (p < 0.000). However, insignificant difference was found for BMI. The BMI [Weight (kg) / Height (cm²)] was used to reflect the nutritional status of the studied samples. It was classified into 4 categories according to WHO [21], Gronder et al. [22] Classification.

Table 2. Comparison of mean (± SD) of body weight, length and BMI between acne patients and controls in Upper Egypt

3.2. Diet and Acne

Comparison of diet intake between patients and controls was shown in Table 3. There were significant differences (p< 0.05) between patients and controls in consumption of chocolate, peanut, rice, corn, macaroni, potato, vegetables, butter, fat, beef, chips, pizza, cola, fruit juice, spices, pickles, meat, chicken, fish, honey, and tehena. Significant increased consumption of all the previous food stuffs except vegetables & potato were recorded in acne patients compared to controls. However, consumption of fruits, milk, yoghurt, soup, salt fish and treacle recorded insignificant difference.

Table 3. Comparison of diet intake frequencies between acne patients and controls in Upper Egypt

Table 3. Continued

Table 3. Continued

Table 4 outlined the relationship between the three severity degrees of acne and diet. The study showed that certain food stuffs namely: chocolate, fat, beef burger, potato chips and cola recorded significant increased consumption (p< 0.05) ascendingly according to the severity of acne. Significantly decreased consumption of vegetables were noticed among severe and moderate acne patients compared with mild acne patients. However, peanut, rice, corn, macaroni, potato, fruit, butter, pizza, milk, yoghurt, fruit juice, soup, spices, pickles, salt fish, chicken, fish, honey, treacle and tehena recorded insignificant difference. Insignificant decreased consumption of fruit, yoghurt, fish and treacle were recorded in severe acne patients compared with moderate and mild patients.

Table 4. Comparison of diet intake frequencies among the three severity degrees of acne in Upper Egypt

There were statistically significant differences between acne patients and controls regarding the number of vegetarians (p<0.05) (Table 5). In acne patients, 30 (13%) were vegetarians compared to 51 (22.2%) of controls. 72 acne patients (31.3%) took vitamin A and compared to 115 (50.0%) of controls, which were statistically significant (p<0.001). On the other hand, almost all controls and acne patients did not take zinc capsules which was statistically insignificant. Table 5 indicated that there was significant increase in the number of vegetarians, taking vitamin A supplement in controls compared with acne patients.

Table 5. Relationship between vegetarians, taking vitamin A, zinc capsules in acne patients and controls

The study showed that 16 (53.3%) of mild acne patients were vegetarians compared to 13 (43.3%) of moderate and 1 (3.3%) of severe acne patients, which was statistically insignificant. The data revealed that 37 (51.4%) of mild acne patients took vitamin A compared with 33 (45.8%) of moderate acne and 2 (2.8%) of severe acne patients, which was statistically significant (p<0.05) (Table 6).

Table 6. The relationship between patients of the three degrees of acne severity and vegetarians, taking vitamin A and zinc capsules

Table 6 indicated that there was significant difference for taking vitamin A between the three severity degrees of acne. However, only 3 moderate acne patients out of 112 took zinc capsules. Therefore, table 6 indicated no significant difference for taking zinc capsules between the acne three severity degrees.

4. Discussion

Acne vulgaris is the most common skin disease, affecting nearly 80% of individuals at sometime in their lives. The relationship between diet and acne has been called into question [8]. Our study showed that acne was significantly increased in younger age patients (< 20 years old), females, with higher educational level, medium family income and in patients with positive family history of acne. Such data are in good agreement with some authors findings. [2, 10, 16, 23, 24]. The study revealed significant difference between acne patients and controls for weight and length. However, no significant difference was detected for the BMI. The theory postulating link between BMI and the development of acne is far from being proved, which quite agree with Ferdowsian and Levin findings [10]. However Landro et al. [25] reported that family history, BMI, selected dietary factors may influence the risk of moderate to severe acne.

Significant increased consumption of chocolate, peanut, rice, corn, macaroni, butter, fat, beef burger , chips, pizza, cola, fruit juice, spices, pickles, meat, chicken, fish, honey, and tehena were recorded in acne patients compared with controls. Moreover, significant decreased consumption of vegetables & potato were found in acne patients than control. Koku et al. [26] showed that fat, sugar and fast food consumption was positively correlated with acne prevalence.

The study revealed that chocolate, fat, beef burger, potato chips and cola recorded significant increased consumption ascendingly according to the severity of acne. Significantly decreased consumption of vegetables were noticed among severe and moderate acne patients compared with mild ones. Our findings are in good agreement with [1, 3, 7-11, 21, 23, 27-31] findings. This suggested that nutrition-related lifestyle factors play a role in acne pathogenesis.

It is note worthy that there was contradiction in the association with diet and acne. Some authors reported that chocolate did not aggravate acne [27, 29, 32-34] and the severity of acne did not change after chocolate intake. However, other author stated that acne was exacerbated by certain aspects of diet including chocolate [3].

On the other hand, the LGL diet may reduce acne [14, 16, 35]. Increased glycemic load (GL) may result in increased activity of sex hormones and insulin like growth factor-1 (IGF-1), thereby contributing to acne development [4, 36]. Kwon et al [37] confirmed that the intake of LGL diet for 10 weeks resulted in clinical improvement in the number of non inflammatory and inflammatory acne lesions in Korean patients. Paoli et al. [38] supported an influence of various dietary components on the development of acne particulary focusing on the role played by carbohydrates. They reported the therapeutic potential of ketogenic diet in acne.

Furthermore, some authors stated that acne is positively associated with intake of milk (particularly skim milk). Association between acne and dairy products may be caused by hormones and bioactive molecules present in milk. These factors may be more bioavailable in skim milk [13, 15, 30]. However, Anderson [29] reported that milk did not produce any acne flares. The high GL pathway and increased consumption of milk & its products aggravate mammalian target of rapamycin complex 1 (m TORC1) signaling in acne [39, 40].

Furthermore, both roasted peanut and cola did not produce any acne flares [29]. On the contrary, the present study recorded significant increased consumption (for cola) and insignificant (for peanut) in the severe acne patients compared with moderate and mild patients.

The list of moderate glycemic diets (moderate glycemic index (MGI) 56-69 using glucose as reference food) recommended for acne patients are outlined in (table 7) [14].

Table 7. List of moderate glycemic diets. (MGI 56-69 using glucose as reference food)*

No clinical studies had specifically examined the role of dietary fiber in acne treatment [8]. Our study showed statistically significant differences between acne patients and controls regarding the number of vegetarians (p= 0.01), where vegetarians were significantly increased in controls compared with acne patients, and insignificant increase in vegetarians in mild acne patients compared with moderate and severe degrees as well. Smith et al [5] reported that improved acne in patients on a LGL diet might be due to higher daily consumption of dietary fibers.

Dietary vitamin A is obtained either from preformed vitamin A or from provitamin A carotenoids. Most dermatologists are reluctant to recommend oral vitamin A supplements for acne because of the fear of inducing hypervitaminosis A [8]. Our study indicated that there was significant increase in taking vitamin A supplement in controls compared with acne patients (p=0.0001) as well as in mild acne patients compared with moderate and severe patients (p=0.031). However, there was insignificant difference between patients and controls taking zinc capsules. Our results are in good agreement with Kligman et a.l findings [41], who stated that vitamin A was effective treatment for acne patients at doses of 300 000 U for women, and 400 000 U for men. Besides, zinc and minocycline were both effective in treatment of inflammatory acne patients, however, minocycline had superior effect [42].

Recommended and forbidden diets for acne patients:

The list of recommended and forbidden diets for acne patients is represented in Table 8 [4, 7, 14].

Table 8. List of recommended diets and forbidden diets for acne patients

Recent evidence suggested that LGL diets might affect sebum production based on beneficial hormonal effects of these diets [16]. The GL might be interpreted as a measure of the blood glucose and insulin-raising potential of the diet as it represents the rate of carbohydrate absorption (indicated by the GI) and the quantity of carbohydrate consumed [4, 43].

The recommended LGL diet consisted of 25% of energy from protein, 45% from low GI carbohydrates, and 30% energy from fats [5].

It is note-worthy that daily dietary glycemic index (GI) and GL were calculated from diet records. Dietary GI was calculated as ∑(GI for food item x proportion of total carbohydrate contributed by item), and the GL was calculated as ∑(GI for food item x its carbohydrate content in grams/100) [5]. The GI values used had glucose as the reference food and were taken from Table 8 [4, 7, 14].

A recommended diet regime set up by the author [19] was given in Table 9.

Table 9. Recommended dietary regimen for acne patients*

Conclusion and general recommendation for acne patients:

The present study found significant differences between patients & controls as well as between different severity degrees of acne patients for the consumption of chocolate, peanut, rice, corn, macaroni, potato, vegetables, butter, fat, beef, chips, pizza, cola, fruit juice, spices, pickles, meat, chicken, fish, honey and tehena. However, fruits, milk, yoghurt, soup, salt fish and treacle recorded insignificant difference. This suggests that nutrition-related lifestyle and dietary composition factors play a role in acne pathogenesis.