Diet & Acne: Is there a link?
The idea that acne is caused by a poor diet is still considered a myth.
Diet does not generally affect acne even though many people think that chocolate makes their acne worse (1).
Some evidence suggests that dairy products and high glycaemic index foods aggravate (but do not cause) acne (1).
High GI foods are carbohydrate foods that are broken down quickly by your body and cause a rapid increase in blood glucose.
Some high GI foods are (2):
sugar and sugary foods
sugary soft drinks
white bread
potatoes
white rice
Switching to a low GI diet may lead to fewer spots.
There is also some evidence that consuming milk and dairy products may trigger acne in some people, but this hasn't been studied in as much detail yet (3).
There are a lot of studies out there about restricting food in the diet of people with acne and most of these are observational studies.
Observational studies are ones where researchers observe the effect of a risk factor/ intervention without trying to change who is or isn’t exposed to it.
But the problem with these studies is that a multitude of factors can affect your skin and so far the evidence is not robust enough to control for these other factors.
Essentially, even though people eating chocolate in a study had worse acne, they may also have been doing other things that aggravated acne.
NICE have completed an evidence review for dietary interventions for the treatment of acne guidelines and reviewed the evidence from 4 randomised controlled trials that examined the effectiveness of following a low GI diet. 2 of these studies showed an improvement in outcomes but only one showed a clinically important impact on acne lesions. The issue is this study was small and there was a serious risk of bias. It also showed that a low GI diet led to an important reduction in weight compared to those with an unrestricted diet. The concern here was that although weight loss and restricted food intake could be beneficial for some, it could also cause problems in others (for example people who may not be overweight) Following a low GI diet involves a lot of effort and such a strong focus on food intake could contribute to the development of eating disorders (as most people with acne are young and the onset of eating disorders is most common in adolescence) (4).
Given the limited amount of good quality research, the NICE committee recommend that people should be advised about
the lack of evidence to support specific diets (4).
The best advice is as always to eat a balanced healthy diet.
If you think a certain type of food is aggravating your acne, you can exclude it from your diet for six weeks to see if it has an affect. If you are cutting out high GI foods, be sure to see your practitioner first
and make sure your get appropriate dietary counselling and weight monitoring.
Diet and its link with acne is a promising area of research and more randomised control trials are needed to explore this.
Sources:
Electronic Therapeutic Guidelines Australia. Available from: https://tgldcdp.tg.org.au/viewTopic?etgAccess=true&guidelinePage=Dermatology&topicfile=c_DMG_Acne_topic_1&guidelinename=Dermatology§ionId=toc_d1e639#toc_d1e639
NHS What is the Glycaemic Index (GI)? Available from link: https://www.nhs.uk/common-health-questions/food-and-diet/what-is-the-glycaemic-index-gi/
British Association of Dermatologists Acne. Available from link: https://www.bad.org.uk/pils/acne/
Acne vulgaris: management [C] Dietary interventions for the treatment of acne vulgaris NG198 Evidence review underpinning recommendations 1.3.1 and research recommendation 3 in the NICE guideline June 2021