Diabetes is a frequent disease characterized by chronic hyperglycemia, and its prevalence is increasing worldwide. Historically, patients with diabetes were required to monitor capillary blood glucose concentration up to several times a day through fingertip sampling.

Recently marketed devices now allow measurements of interstitial fluid blood glucose continuously, thus limiting pain associated with sampling. However, they are still invasive and have to be changed every 14 days.

Therefore, to optimize continuous glycemia monitoring while avoiding pain, discomfort, and the risk of infection, non-invasive methods are needed. Among the different strategies being developed, optical wearable sensors with specific signal processing are a promising option. The sensors detecting this optical signal will be included in a device. Yet, wearing a device may slightly modify several properties of the skin, such as its humidity and thermal regulation, and subsequently have an impact on the measured optical signal. Therefore, it is important to better understand how a device affects these characteristics to include these parameters in the future device algorithms.

Inclusion Criteria:

• Male or female aged ≥ 18 years and ≤ 60 years
• Signed informed consent
• Person who is affiliated to a social security scheme or who is beneficiary of such a scheme

Exclusion Criteria:

• Body mass index (BMI) > 30 kg/m2
• Any acute or chronic disease with vascular impact
• Any cutaneous disease on sites implicated in the study (dorsum of the forearm)
• Allergy to one of the material used in the sham device and during the procedure of the study
• The persons mentioned in articles L1121-5 to L1121-8 of the public health code may not be included in this research
• Subject who would receive more than 4500 euros in compensation due to his or her participation in other research involving the human person in the 12 months preceding this study