Diet Modification

Dietary modification is considered the cornerstone in the management of T2DM. More than three out of every four adults with T2DM are at least overweight (Ali et al., 2013) and nearly half of individuals are obese (Nguyen et al., 2011). Due to this relationship between body weight (i.e., adiposity) and insulin resistance, weight loss has long been a recommended strategy for overweight or obese adults with diabetes (ADA, 2014) and several large scale studies have tried to assess the impact diet and exercise can have on health.

The Finnish Diabetes Prevention study (FDP) randomized 522 overweight subjects with IGT to usual care or diet and exercise recommendations. The dietary goals in the interventional group were a low fat-diet (<30% fat energy as fat) with, 10% saturated fatty acids (SFA) and dietary fiber >15g/1000Kcal. Participants in this group were instructed to increase physical activity to attain the target of weight loss to nearly 5% of baseline weight. The cumulative incidence of T2DM was 23% in the control group and 11% in the intervention group. Interestingly, risk reduction was directly proportional to the magnitude of lifestyle changes. Despite the success of many lifestyle trials, an important question remained to be answered. Weight loss appeared to be the driving force to reduce incidence of T2DM. Thus it is unclear whether diet with its macronutrient composition or exercise alone plays a significant role in preventing T2DM (Tuomilehto et al., 2001).

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Salas-Salvadó and colleagues concluded -after reviewing epidemiologic and clinical trial evidences relating nutrients, foods and dietary to T2DM risk as well as the differential effects of carbohydrates and fat quantity and quality – that there is no universal dietary strategy to prevent T2DM or delay its onset. Furthermore, maintaining ideal body weight and consumption of the so- called prudent-diet (characterized by high intake of plant-based foods and lower intake of red-meat, sweets, high-fat dairy products and refined grains or a Mediterranean dietary pattern rich in olive oil, fruits and vegetables, including whole grains, pulses and nuts, low- fat dairy, and moderate alcohol consumption (mainly red wine)) appears as the best strategy to decrease T2DM risk, especially if dietary recommendations takes into account individual preferences, thus enabling long-time adherence (Salas-Salvadó, 2011). Furthermore, the low-fat eating pattern is one that has often been encouraged as a strategy to lose weight or to improve cardiovascular health within the U.S. In the Look AHEAD trial (Look Ahead Research Group, 2013), an energy reduced low-fat eating pattern was encouraged for weight loss, and individuals achieved moderate success (Pi-Sunyer et al., 2007). However, in a systematic review (Wheeler et al., 2012) and in four studies (Brehm et al., 2009; Davis et al., 2009; Guldbrand et al., 2012; Papakonstantinou et al., 2010) and in a meta-analysis (Kodama et al., 2009), lowering total fat intake did not consistently improve glycaemic control or CVD risk factors. The benefit gained from a low-fat diet appears to be more likely to occur when energy intake is also reduced and weight loss occurs (Pi-Sunyer et al., 2007; Look Ahead Research Group, 2013).

A variety of diets have been proposed to treat obesity. Although many different dietary approaches may result in short term weight loss, the limitation of most diets is the poor long-term compliance and weight regain. There is no “ideal”

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conclusive eating pattern that is expected to benefit all individuals with diabetes (Wheeler et al., 2012).

Despite all these promising results, few studies have addressed the effects of dietary intervention and life style changes on dietary fat intake and endotoxin levels and their correlation with insulin resistance, therefore our study sought to establish whether a high-fat meal increased circulating endotoxin and inflammatory markers and whether this is altered in different metabolic disease states, as well as to study the effectiveness of dietary intervention through low fat, complex carbohydrate diets in decreasing inflammatory markers related to obesity among metabolically dysfunction states .

Currently we have very limited evidence in the field of metabolic disease regarding the importance of dietary intervention, what works, and how diets exacerbate inflammatory risk. However, this study, while challenging, has the appropriate infrastructure, including primary care networks, to provide novel and exciting data. The work detailed in this study will generate a large body of significant data with potential ramifications for clinical practice as we reassess the effects of feeding and dietary patterns. Based on pilot data, this study will highlight the factors that may increase our inflammatory risk, their temporal profile, and how they differ among NOCs, overweight and subjects with T2DM. We will also examine how, over time, a change in diet may reduce our inflammatory risk. As such we anticipate that a low fat diet will reduce inflammatory status impacting long-term pathological outcome such as CVD. Obviously, this is expected to have a fundamental impact on targeting therapeutic approaches for T2DM towards treating the inflammatory component of the disease, especially after verifying the results in a

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larger patients population. Reducing the pathogenesis of T2DM by dampening the inflammatory response, which may also have an impact on insulin resistance status and general health of the individual, will have clear benefits. This could have profound effects on preventative T2DM management, as well as current T2DM care without excessive cost for the wider Saudi health economy.

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