Role of Mediterranean Diet in Managing Type 2 Diabetes Mellitus

This literature review investigates the effectiveness of the Mediterranean diet (MedDiet) in managing type 2 diabetes mellitus (T2DM). It explores the role of MedDiet as a non-pharmacological intervention, highlighting its potential to reduce the severity of T2DM and improve overall health outcomes. The review synthesizes findings from various studies, including randomized control trials and meta-analyses, to demonstrate how MedDiet components, such as high plant-based food consumption and olive oil, can modulate metabolic pathways, improve glycemic control, and reduce cardiovascular risks. The review also addresses research gaps, particularly regarding the carbohydrate content of the MedDiet, and concludes that the MedDiet is a promising approach for effective T2DM management by reducing blood glucose levels, improving the lipid profile, and decreasing the risk of microvascular complications. Overall, the literature review emphasizes the importance of the MedDiet in T2DM management.

Running head: LITERATURE REVIEW
Literature Review
Name of the Student
Name of the University
Author Note

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LITERATURE REVIEW
Introduction
Australian Institute of Health and Welfare (2019) stated that type 1 and type 2
diabetes mellitus accounted for 0.3% and 2.2 % of overall disease burden in Australia in the
year 2015. The poor socio-economic status is associated with higher incidence and
prevalence of diabetes related hospitalization and death. Approximately 1 million of
hospitalizations are associated with diabetes development in 2016 to 2017. It is estimated that
nearly 1.2 million Australian adults are suffering from diabetes (2017 to 2018). () are of the
opinion that improvement in the lifestyle conditions like physical activity and diet helps to
reduce the chances and severity of developing typ1 and type 2 diabetes will a special mention
to type 2 diabetes mellitus (T2DM). The following literature review will focus on the role of
non-pharmacological intervention like the consumption of the Mediterranean diet in effective
diabetes management.
Rationale
The rate of occurrence of T2DM is higher than T1DM and mainly the older adults are
victims of T2DM. Poor lifestyle condition, consumption of alcohol, smoking of cigarettes,
sedentary lifestyles are the principal factors behind the development of T2DM among the
older adults. T2DM is insulin independent diabetes mellitus are thus improvement of the
lifestyle factors are the principal interventions behind the effective management of T2DM
(Zinman et al., 2015). Inzucchi et al. (2015) and Fuchsberger et al. (2016) are of the opinion
that older adults who are over 65 years of age experiences problems in conducting regular
physical activities due to neurological complications and pain in the joints. Thus, proper
management of diet is regarded as promising interventions for the effective management of
T2DM. Traditional anti-diabetic diet include low carbohydrate and low sugar diet. However,

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recent advancement in the domain of non-pharmacological interventions laid to the
foundation of new dietary management for T2DM that is Mediterranean diet.
Research question
What is the effectiveness of MedDiet in controlling the severity of T2DM over adults?
Literature Research Strategy
Inclusion Criteria Exclusion Criteria
Papers published within last 10 years Papers published before 2011
Peer-reviewed journals
Studies published in English
List of keywords Boolean Operators used List of databases
Mediterranean diet AND/ OR Cochrane
Type 2 diabetes Mellitus, Type2
Diabetes, diabetes
PubMed
Management PsycInfo
Control CINHAL
Review of Literature
Several studies have provided evidences supporting the importance of the
Mediterranean diet (MedDiet) on managing the vulnerability of type 2 diabetes mellitus
(T2DM) and other metabolic syndrome (MetS). The review conducted by Salas-Salvadó et al.
(2015) over the present scientific evidence gathered from currentgic studies and other clinical
trial showed that MetDiet can help to reduce the severity of T2DM and as well as gestational

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diabetes in comparison to the low sugar diet. MedDiet helps to reduce the central obesity by
improving the basal metabolic rate (BMR) and thereby helping to reduce blood glucose level
(BGL) and severity of T2DM. Mainly the components of MedDiet modulate various
metabolic pathways and this again helps to reduce the cardio-metabolic disease risk. The
systematic review and meta-analysis conducted by Schwingshackl, Missbach, König and
Hoffmann (2015) also showed similar results like Salas-Salvadó et al. (2015). The review of
the randomized control trials (RCTs) and cohort studies published during 2007 to 2014
showed that higher adherence to Mediterranean diet is associated with significant decrease in
the vulnerability of developing diabetes. The prospective study conducted by Esposito,
Maiorino, Bellastella, Panagiotakos and Giugliano (2017) helped to understand a new
perspective of MedDiet. MedDiet is rich is high in plant-based foods and olive oil and low-
to-moderate in consumption of diary, fish and other poultry and meat products. This reduced
amount of animal fat in the diet helps to reduce the level of glycosylated hemoglobin in the
blood by 0.30 to 0.47%. It also helps in reducing the cardio-metabolic threats associated with
the diabetes development by lowering the blood cholesterol level. The increased consumption
of plant rich food helps to e increase the percentage of anti-oxidants and anti-inflammatory
cytokines while reducing the secretion of pro- inflammatory cytokines. This in turn helps to
improve the insulin sensitivity in the peripheral tissues and helping to reduce the BGL. The
study conducted by Itsiopoulos et al. (2011) also showed similar results like Esposito et al.
(2017). The study showed that traditional moderate fat MedDiet helps in improving glycemic
control and quality of diet in both men and women with well-controlled T2DM without
having any adverse effects on weight management. However, the study was conducted only
over individuals with well-controlled T2DM and thus hindering mass based MedDiet
application approach for example with adults with uncontrolled T2DM.

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The role of the MedDiet over cardiovascular risk factors was further highlighted in
the systematic review and meta-analysis conducted by Esposito et al. (2015). The study
showed that MetDiet helps in better glycemic control and reduced risk of cardiovascular
disease among T2DM patients t also helps in reducing the concentration of high-density
lipoprotein in blood serum and this is suitable for effective management of type 2 diabetes.
The intake of low fat diet with reduced consumption of animal meat is not associated with the
threat of developing weakness or malnutrition because the prospective cohort study by
Lopez-Garcia et al. (2018) showed that MedDiet pattern help to reduce the risk of frailty
among older women with T2DM. However the study failed to interpret its affect over men.
Apart from reducing the risk of frailty and cardiovascular co-morbidities, MedDiet also helps
in reducing the severity of diabetic retinopathy, nephropathy and other microvascular
complication of diabetes. Reduction in the micro-vascular complications associated with
diabetes make MedDiet suitable for the patients who are suffering from T2DM for a
significant period with unmanaged BGL (Díaz-López et al., 2015). Another study conducted
by the American Diabetes Association showed that MedDiet without any significant calorie
restriction is effective in preventing the T2DM development among the subjects with high
cardio-vascular risk factors. The ease of calorie intake in MedDiet promote increased
adherence of the diet with decreased level of monotony or depression associated with limited
food intake (Salas-Salvadó et al., 2011). The importance of the olive content and high level of
plant products in the MedDiet helps to increase the BMR while reducing the BMI level as
indicated in the qualitative review conducted by Pérez-Martínez et al. (2011) and thus further
emphasizing the results elucidated by Esposito et al. (2015).

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Research Gap
The main research gap is there is no significant information regarding the
carbohydrate content of the Mediterranean diet. Low carbohydrate diet is also a prime focus
for the effective management of the T2DM at present. The randomized control trial
conducted by Tay et al. (2015), over 115 obese T2DM individuals with high body mass index
(BMI) and high level of glycated hemoglobin (HbA1c) showed that both the diets (high-
carbohydrate low fat diet [HC] and high-unsaturated fat and low-saturated fat diet [LC])
helps in achieving significant weight loss and reduction in HBA1c and fasting glucose. LC
diet that was high on unsaturated fat and low in saturated fat helped to achieve greater
improvements in the lipid profile, stability of fasting blood glucose and reductions in the
requirement of diabetes medications. Thus, evaluation of the carbohydrate content of
MedDiet will help in ascertaining the local food availability of the diet and making the diet
suitable for all individuals irrespective of the socio-economic group (Koloverou et al., 2014).
Conclusion
Thus from the above discussion it can be concluded that carbohydrate diet helps in
effective management of T2DM by reducing the blood glucose level, level of BMI and
increasing the BMR. It also helps in reducing the cardiovascular effects associated with
T2DM along with reduction in the severity of micro vascular complications of diabetes.
Evaluation of the local availability of the diet will help increase adherence of the diet plan
among the mass.

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