29 May 2020
Acne and diet- Bubble tea, ice-cream and chocolate lovers of the world, unite… and put that aside for now. If you have acne or acne-prone skin,some foods can worsen your acne. Today’s blogpost will examine the role of diet and acne, and how some common foods are linked to acne.
For a comprehensive review on acne types, causes of acne; and how to treat acne (including acne skincare ingredients), please read A Guide to Acne: Types, Causes, Treatments and Tips for Prevention. Although hormones and Cutibacterium acnes bacteria play major roles in worsening breakouts; our diets and skincare choices can also affect acne control.
There is compelling evidence that diet affects acne. The role of high-glycemic index foods and milk/dairy in acne have been commonly examined and here’s what the evidence shows. You might be surprised at some of the interesting findings:
Emerging data shows that high glycemic diets may be linked to acne. Several studies show that high glycemic diets worsen acne.
The glycemic index is a relative scale from 1-100 that ranks the rise in blood glucose level after consuming the food. The higher the glycemic index for a particular food; the higher the blood sugar level rises after consumption. Insulin levels in the blood also rise in correspondence to the raised blood sugar level. Foods with an index of more than 70 are considered to be high glycemic index foods. Examples of high glycemic index foods are glucose containing drinks. This list from Harvard Medical School shows the glycemic index of common foods in our diet. Bubble tea and dessert lovers are you reading this?
High glycemic foods cause a surge in blood glucose and insulin levels after consumption. Raised insulin levels trigger several hormone changes, leading to raised hormones (androgen and insulin-like growth factors) and protein (insulin-growth factor binding protein). These hormones and proteins enhance key steps in the formation of acne such as increased sebum production and comedogenesis.
On the flipside, low glycemic foods have been associated with reduced acne.
Researchers have found that some indigenous populations have a very low prevalence of acne. Traditionally, Canadian Inuits,pre-World War II Okinawans, and Zulu populations do not have acne. However, acne prevalence increased in Canadian Inuits after cultural assimilation with neighbouring countries and adoption of processed foods, beef, and dairy. Similarly, the incidence of acne increased among pre-World War II Okinawans following consumption of animal products.
A few studies also show that low-glycemic index diets lead to improved acne severity. However, more robust studies are required to validate this finding.
Conclusion on high glycemic index food and acne:
The link between high glycemic index food and worsening acne is compelling. If you have a high glycemic index diet, the recommendation by dermatologists is to switch to a low glycemic index diet.
Milk and dairy products have also been linked to acne vulgaris. However, the findings may surprise you!
Several observational studies show that all types of milk (whole milk, low-fat milk and skim milk) and some dairy products may aggravate acne. The association is strongest for skim milk, as compared the other types of milk. However, more studies and trials are needed before restrictions on milk or whey consumption can be recommended.
It is believed that milk contains bovine insulin-like growth factor (IGF-1). Bovine IGF-1 stimulates the cascade of hormone reactions similar to human IGF-1 when high GI foods are consumed, leading to comedogenesis. Besides IGF-1, cow’s milk also contains various other hormones such as bovine androgens, estrogen and progesterone hormones. These hormones also stimulate sebum production and hyperkeratinisation in humans.
Studies also show that skim milk is more comedogenic than whole milk. As compared to whole milk, skim milk has fat removed and is considered to be more concentrated in nutrients. The benefit of consuming skim milk is that it contains a higher amount of calcium, vitamin D and proteins. The reasons why skim milk has a stronger association is still not known. It is thought that the higher concentration of milk proteins (whey and casein) increase acne by cellular and hormonal pathways too. This is one of possible reasons why whey protein supplements popular among sportsmen, may cause acne.
For dairy products, ice-cream and chocolate have been implicated in acne vulgaris. On the other hand, cheese and yoghurt consumption have not been found to exacerbate acne. Phew- I’m a cheese lover!
Conclusion on milk and dairy products and acne:
There is some evidence that milk and dairy products, in particular skim milk, may influence acne vulgaris.
Chocolate has also been frequently linked to acne. Some dermatologists have also reported onset of new pimples in patients a few days after consuming chocolate. While chocolate causing acne is not a myth; the evidence behind it is still limited. Whether the type of chocolates- dark or milk- chocolates aggravates acne, is also unclear.
Although we do not know enough about the details linking chocolate intake and acne, my recommendation is to cut down on chocolates where possible.
Studies are equivocal on whether fatty food, specifically omega-6 fatty acids cause acne. Currently, most dermatological associations do not suggest dietary restrictions on fatty food. The findings on whether ‘good’ fats like omega-3 fatty acids can reduce acne is also equivocal.
Probiotic drinks and supplements can help to improve acne in small studies. You can read more about it in this blogpost Probiotics in Skincare and Supplements: Do They Work? The evidence for probiotics is still preliminary so probiotics might be helpful. However, most doctors do not recommend probtiocs over first line treatment for acne vulgaris, namely retinoids.
So the conclusion is, yes your diet can impact acne. However, a lot more studies are still needed to ascertain findings before for more specific recommendations can be made. We do know that some foods are linked to acne; but the details are still a gap in our knowledge.
My take is that acne is highly personal; and we need to look at each patient holistically before making blanket recommendations. My recommendation for you is to notice whether your breakouts are linked to any particular food or drink (you can keep an acne diet diary). Try eliminating that food or drink for a month and see how your skin recommends. Effective acne treatment results require a multi-pronged approach including skincare changes. Some patients may also require medications and in clinic treatments like Q-switched lasers and chemical peels. Your diet is one aspect where you can take ownership and try to improve your acne.
In summary, the evidence is strongest for high glycemic index diets; so low glycemic index diets are recommended if you have acne. There is some, but less convincing evidence that milk, in particular skim milk, can worsen acne. My suggestion is to cut back on skim milk where possible. Even weaker is the evidence for chocolates and acne; even though they may be linked.
Oily and fatty food do not seem to be linked to acne, so we can rejoice! Time to put aside the bubble tea and get some fries (don’t mind me). Consider probiotics on top of your acne medications too.
Hope you enjoyed this post on diet and acne! Please feel free to share this post if you found it useful. The link between milk and dairy products is less convincing, but should not be ignored in my opinion. My recommendation is to reduce skim milk.
If you would like to read more acne related blogposts, here they are:
1. Acne Management Guidelines by the Dermatological Society of Singapore. Oon et al. J Clin Aesthet Dermatol. 2019 Jul; 12(7): 34–50.
2. Significance of diet in treated and untreated acne vulgaris. Kucharska et al. Postepy Dermatol Alergol. 2016 Apr; 33(2): 81–86.
3. Acne: the role of medical nutrition therapy. Burris et al. J Acad Nutr Diet. 2013 Mar;113(3):416-30.
4. Guidelines of care for the management of acne vulgaris. Zaenglein et al. J Am Acad Dermatol. 2016 May;74(5):945-73.
5. Diet and acne. Bowe et al. J Am Acad Dermatol. 2010 Jul;63(1):124-41.