SKINIPEDIA - Skin Encyclopedia: Milk & Teenage Girls Acne
Milk consumption and acne in adolescent (teenage) girls
Study by Clement A Adebamowo, Donna Spiegelman, Catherine S Berkey, F William Danby, Helaine H Rockett, Graham A Colditz, Walter C Willett, Michelle D Holmes, Dermatology Online Journal
Abstract
There has been a remarkable paucity of evidence for an association between diet and acne. Our previous studies suggest that there is an association between milk intake and teenage acne. This is a prospective cohort study to evaluate that relationship. We studied 6,094 girls, aged 9-15 years in 1996, who reported dietary intake on up to three food frequency questionnaires from 1996 to 1998. Presence and severity of acne was assessed by questionnaire in 1999. We computed multivariate prevalence ratios (PR) and 95 percent confidence intervals for acne. After accounting for age at baseline, height and energy intake, the multivariate PRs (95 % CI; p-value for test of trend) for acne comparing highest (2 or more servings per day) to lowest (<1 per week) intake categories in 1996, were 1.20 (1.09, 1.31; <0.001) for total milk, 1.19 (1.06, 1.32; <0.001) for whole milk, 1.17 (1.04, 1.31; 0.002) for low fat milk and 1.19 (1.08, 1.31; <0.001) for skim milk. This result did not change appreciably when we excluded girls who reported use of contraceptives and when we restricted our analysis to those younger than 11 years of age at baseline. We found a positive association between intake of milk and acne. This finding supports earlier studies and suggests that the metabolic effects of milk are sufficient to elicit biological responses in consumers.
Introduction
Teenage acne is a common, chronic and self-limiting skin disease that is associated with physical and psychological morbidity in up to 90 percent of adolescents and young adults. In Western countries, acne affects all ages, but its maximum prevalence peaks at 16-18 years when 75-98 percent of this age group is affected. Acne is more common in girls, both overall and below the age 12 years.
Acne results from hyperkeratinization and obstruction of the pilosebaceous follicles secondary to androgen-stimulated failure of normal desquamation of the follicular epithelium, androgen-stimulated sebum production, subsequent colonization of the follicles by Propionibacterium acnes and other organisms, and variably, inflammation. Ecological studies suggest an association between the Western diet and acne, but the relevant dietary factors are unclear. At least one clinical trial failed to find an association with chocolate intake. In another study, subjects were fed large quantities of foods that they claimed worsened their acne but no acne flares occurred. Robinson reported that among 1,925 patients who kept a food diary, the majority implicated milk in acne flares. In a previous study of US female nurses who reported their high school diet and the prevalence of physician-diagnosed severe teenage acne, we found a positive association with intake of total and skim milk.
In this study, we examined data from a prospective study of US youth to evaluate intake of dairy foods and other factors in relation to occurrence of acne among girls. The study was approved by the Institutional Review Boards of the Brigham and Women's Hospital and the Harvard School of Public Health.
Methods - Study population
The Growing Up Today Study (GUTS) is an ongoing cohort study of 9,039 girls and 7,843 boys, aged 9-15 years at baseline in 1996. These patients were followed by yearly questionnaire to ascertain lifestyle factors. Participants are offspring of the women in the Nurses Health Study II (NHS II) cohort and have been described in detail elsewhere [8]. In this analysis, we examined the association between milk consumption and occurrence of acne among female members of the cohort. After exclusion of participants who had implausible values ( <500 and >5000 kcal/day) for energy intake (n = 96), those who left more than 70 response items blank (n = 33), and those who did not respond to the 1999 questionnaires that contained the acne question (n = 2,945), there were 6,094 girls who completed a detailed food frequency questionnaire (FFQ) in 1996 and another FFQ in either 1997 or 1998.
Semi-quantitative food-frequency questionnaires and calculation of nutrient intake
The development and validation of the GUTS food-frequency questionnaire has been previously described [9, 10]. In brief, participants were asked how frequently they used a typical portion size of specified foods on average during the past year. The dairy food group included total milk, chocolate milk, instant breakfast drink, ice cream, yogurt, cottage cheese, cream cheese, other (hard) cheese, frappe (milkshake), and butter. In addition they were asked "What type of milk do you usually drink" and the options were 'whole milk', '2 percent milk', '1 percent milk', 'skim/nonfat milk', 'soy milk', 'don't know', and 'don't drink milk'. Consumption of the specific types of milk was derived from the cross-classification of the responses to the usual type of milk consumed and the frequency of total milk consumption. Whole milk and 2 percent milk were grouped because of their similar fat content. Other food items that were studied include French fries, pizza, and chocolate candy because these have often been perceived as causes of acne. The response categories for some of the food items such as non-milk dairy foods, pizza, French fries and chocolate candy were collapsed because of small cell sizes.
Milk consumption and acne in adolescent girls Study Part 2 is HERE