Does sugar worsen eczema?

Eczema is an inflammatory skin condition characterised by the presence of red patches on the skin accompanied by an intense itching sensation. There are several types of eczema, among which is atopic eczema, very common and also known as atopic dermatitis. This form of eczema develops in individuals with a genetic predisposition to atopy, making them highly sensitive to common allergens in their environment. In the case of atopic eczema, the skin barrier does not perform its role correctly, leading to excessive water loss and increased permeability to allergens. Eczema can also be acquired and present without a genetic predisposition, in the form of contact eczema or allergic eczema.

No matter the form ofeczema, skin lesions follow four main stages. They initially appear red and warm, sometimes swollen, and are accompanied by itching. A few hours later, small vesicles filled with clear fluid appear on the red lesions and the itching persists. Scratching then breaks the vesicles which begin to ooze. They then become crusts and heal. However, the healing process is in some cases more difficult than in others and it happens that the eczema worsens.

Sugar is a vital energy source for the cells in our body. Brain, muscles... These various organs could not function without it. Moreover, sugar can activate the reward system in the brain, stimulating the release of dopamine and endorphins, neurotransmitters associated with pleasure and well-being. This can contribute to a feeling of satisfaction and mood enhancement. However, when it comes to eczema, sugar often gets a bad press.

Indeed, some studies attribute to added sugar, which is different from the sugar naturally present in fruits and vegetables, inflammatory effects. These research works suggest that sugar can activate the tumour necrosis factor (TNF-α) and the production of interleukin-17 (IL-17), pro-inflammatory cytokines that can exacerbate redness and itching due to eczema. However, these mechanisms are controversial and not all studies agree that sugar worsens eczema.

One of the most recent studies focusing on this issue concluded that sugar was not an exacerbating factor for eczema. This research involved 30 volunteer participants prone to atopic dermatitis. Guided by dieticians for three weeks, half of the patients followed a diet with a very low sugar content, while the others followed a more sugary diet. At the end of the period, SCORAD (SCOring Atopic Dermatitis) measurements were taken. SCORAD is a clinical tool used to assess the extent and severity of eczema, as well as the psychological impact on patients. The measurements of this indicator showed no difference between the two groups, leading the scientists to conclude that sugar was not an exacerbating factor for eczema.

Note : Although a link between sugar and eczema has not been proven, it is important to remember that an excess of sugar in the diet can lead to several health problems, such as cardiovascular diseases, dental issues, weight problems...

• SUBERBIER T. & al. Sugar is not an aggravating factor in atopic dermatitis. Acta Dermato-Venereologica (2001).

• SAURAT J. H., LACHAPELLE J. M., LIPSKER D., THOMAS L. et BORRADORI L. Dermatologie et infections sexuellement transmissibles. Elsevier Masson (2017).