**1. Introduction**

Type 1 diabetes mellitus (T1DM) is an insulin-dependent, multifactorial autoimmune disease, which results in degradation of the beta cells of the islets of Langerhans, which causes impaired insulin production and secretion. The treatment method consists of functional intensive insulin therapy delivered by multiple daily injections (MDIs) using an insulin pen, or a device called personal insulin pump, enabling continuous subcutaneous insulin infusion (CSII), which better mimics the physiological rhythm of insulin secretion [1].

COVID-19 (coronavirus disease 2019) is an acute infectious respiratory disease caused by the SARS-CoV-2 virus (severe acute respiratory syndrome coronavirus). It was first recognized and described in November 2019 in central China (Hubei province). It is considered that the origin of this virus was a seafood market where other animals such as snakes, frogs and bats were also sold. The genome of SARS-CoV-2 is known to be similar to the bat coronavirus and one unrecognized coronavirus, probably the pangolin coronavirus [2].

The Mediterranean diet (MD) is a dietary pattern, the benefits of which are supported by a large body of scientific evidence that highlights the potential health benefits of ad-

**Citation:** Grabia, M.; Pu´scion-Jakubik, A.; Markiewicz-Zukowska, R.; Bielecka, ˙ J.; Mielech, A.; Nowakowski, P.; Socha, K. Adherence to Mediterranean Diet and Selected Lifestyle Elements among Young Women with Type 1 Diabetes Mellitusfrom Northeast Poland: A Case-Control COVID-19 Survey. *Nutrients* **2021**, *13*, 1173. https://doi.org/10.3390/nu13041173

Academic Editors: Michael Chourdakis and Emmanuella Magriplis

Received: 16 March 2021 Accepted: 31 March 2021 Published: 2 April 2021

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herence. Nowadays, the MD pattern should be considered not only from a nutritional perspective but also in the light of environmental, economic as well as sociocultural factors. MD is related to a lower risk of developing several chronic diseases, such as type 2 diabetes mellitus (T2DM), heart disease and cancer [3,4]. MD has also been shown to improve cognitive functions [5]. The recently updated MD model highlights the need for a sustainable approach to this diet, with special emphasis on decreased consumption of meat, high fat dairy products and processed foods, and increased intake of locally grown fruits, vegetables, legumes, olive oil, whole grains and nuts. Fish, poultry and red wine should be consumed in moderate amounts. Moreover, the MD may provide considerable amounts of antioxidants, polyphenols, carotenoids (such as lycopene and β-carotene), as well as dietary fiber [3,4,6,7]. Also, because of the high consumption of olive oil, especially extra virgin and nuts, it is rich in monounsaturated and polyunsaturated fatty acids. Many studies have linked their high consumption with an improvement in insulin sensitivity, blood lipid profile, and a reduction in systolic and diastolic blood pressure levels, in line with the standards of medical care established by the American Diabetes Association [7–9].

The aim of the study was to assess health and nutritional behaviors, mainly adherence to MD, during the second wave of the COVID-19 pandemic in Poland among women with T1DM, and to compare them with a healthy population. It was undertaken due to the fact that a number of studies have shown a beneficial effect of the MD in people with diabetes mellitus (DM). This is of particular importance in times of the COVID-19 pandemic. Our research is designed to identify the problem, the solution to which may be inclusion of preventive and educational programs aimed at rectifying possible unhealthy habits. Studies assessing health habits (mainly concerned glycemic management) during the COVID-19 pandemic in healthy people; there are few studies among people with DM, and even fewer among those with T1DM.

#### **2. Materials and Methods**
