We are constantly being told that ‘we are what we eat’, so could diet be linked to acne? Helen Garston investigates.

It’s pretty well established that everything we consume affects our health to some degree, and that includes our skin. But can cutting out foods like sugar and dairy help people with acne? Let’s take a look.

What is acne?

Acne (acne vulgaris) is a condition which is characterised by the presence of pimples and black heads around the face, shoulders, back and chest. In more severe cases, it can cause cysts or nodules.

It affects around 3.5 million people in the UK in varying degrees and can be extremely distressing, leading to low self-esteem and depression.

What causes acne?

Acne normally starts during the teenage years because of the onset of puberty and a surge in the hormone testosterone in both boys and girls.

It’s caused by a combination of the skin producing too much sebum and a build-up of dead skin cells which clog the pores and leads to a localised infection or spots.

Can diet affect acne?

Until the 1950s, dermatologists advised people with acne not to eat sugar, chocolate or diary products.  In the early 60s, studies were carried out to see if there was stronger evidence to support this and the conclusion was that diet did not actually affect acne.

In the last 20 years, however, these studies have been revisited and flaws found.  There has since been emerging evidence that sugar, and to a lesser degree dairy products, may indeed affect acne.

Sugar – the new fat?

Most dermatologists and nutritionists now agree that there is evidence to suggest that simple sugars (or simple carbohydrates) may well be part of the problem.

Although it’s not conclusive, some people with acne have reported improvement in their skin when they follow a low-glycemic index (GI) diet, which can be achieved by:

• increasing the consumption of whole grains, fresh fruits and vegetables, fish, olive oil, garlic
• decreasing the consumption of high-glycemic index foods such as white bread, biscuits, cakes, ice creams and bottled drinks.

Consultant dermatologist, Dr Anjali Mahto, explains how it works: “If someone eats refined sugar or a simple carbohydrate such as white bread or a piece of cake, their blood glucose level will go up. As a response their body will release the hormone insulin to try to combat this.

“Once insulin is released, the body will also release other hormones called IGFs (Insulin-like Growth Factors) and these sometimes increase the activity of oil glands which in turn affect hormones such as testosterone which can drive acne.”

Dr Mahto adds: “Guidelines in the US and UK do still clearly state that people should not try to control acne with diet alone as we just don’t have enough evidence, but there does seem to be an emerging link between acne and sugar.”

Can dairy products affect acne?

In his new book Perfectly Clear, consultant dermatologist Dr Nick Lowe says there is less convincing evidence of the link between dairy products with acne.

However, it has been found that skimmed milk could be a trigger for the disease, as opposed to full fat milk which isn’t.

A study published in the Journal of the American Academy of Dermatology in 2015 found that teenagers with acne consumed more low fat or skimmed milk than those who didn’t.

This has less to do with milk being a dairy product and more to do with it having a higher GI index than full fat milk.

One oft quoted example which still divides opinion is the case of the Kitavan Islanders in Papua New Guinea and the Ache tribe in Paraguay.

Both were studied over a period of two years and found not to have one single case of acne, nor even any pimples.

Genetics and environment could be factors but so could diet as these people were hunter gatherers and only ate foods they hunted or grew.

Dr Lowe says: “It’s very difficult to say conclusively whether these people would get acne if they lived in the West. There are other factors involved, such as stress and environment. Maybe their lives are stress-free? Maybe their environment is more conducive to having clearer skin. We can never be one hundred per cent sure.”

Are there other foods that can affect acne?

Nutritionist Dr Adam Cunliffe of South Bank University says: “It’s very difficult to say categorically what does or does not affect acne and this is why we always warn caution about changing dietary habits.

“We used to think oily food equals oily skin but that no longer seems the case. It’s sugar which is the new fat.

“But it’s endlessly difficult to say what is the culprit as there are so many variables, for example a person’s life style, does the person have an allergy, how many times do they wash their bedsheets, what soap do they use, and so on.”

Dr Cunliffe says the following could also be beneficial for acne sufferers but again evidence is not conclusive.

1. Omega 3 oils such as oily fish. These tend to have an anti-inflammatory affect on the body.
2. Vitamin A. Dr Cunliffe says: “You have to be careful as too much can be toxic. It’s involved in the production of skin cells. If you had a deficiency (bad retinol status) you would be expected to have bad skin.”
3. Zinc. Anecdotal evidence suggests Acrodermatitis, a type of skin condition in children, is improved by taking zinc supplements. Dr Cunliffe says: “You would expect someone with lower zinc levels to have poor quality skin so increasing zinc intake could help acne sufferers.

 The Verdict:

The clearest evidence points towards a link between high GI foods (simple carbs and refined sugars) and acne, although doctors do warn this is not the case for everyone.

Useful links-Glycaemic Index Tables:

http://www.weightlossresources.co.uk/diet/gi_diet/glycaemic_index_tables.htm

https://www.diabetes.org.uk/Guide-to-diabetes/Enjoy-food/Carbohydrates-and-diabetes/Glycaemic-index-and-diabetes/