The metabolic syndrome (MetS) is a global public health issue of increasing magnitude. The Asia-Pacific region is expected to be hardest hit due to large population numbers, rising obesity, and insulin resistance (IR). This review assessed the protective effects of dietary patterns and their components on MetS. A literature search was conducted using prominent electronic databases and search terms that included in combination: diet, dietary components, dietary patterns, and metabolic syndrome. Articles were restricted to prospective studies and high quality randomized controlled trials (RCTs) that were conducted on humans, reported in the English language, and within the time period of 2000 to 2012. Traditional factors such as age, gender, physical activity (PA), and obesity were associated with risk of MetS; however, these potential confounders were not always accounted for in study outcomes. Three dietary patterns emerged from the review; a Mediterranean dietary pattern (MDP), dietary approaches to stop hypertension diet (DASH), and the Nordic Diet (ND). Potential contributors to their beneficial effects on prevalence of MetS or reduction in MetS components included increases in fruits, vegetables, whole grains, dairy and dairy components, calcium, vitamin D, and whey protein, as well as monounsaturated fatty acids (MUFA) and omega-3 fatty acids. Additional prospective and high quality RCT studies that investigate MDP, the DASH diet, and the ND would cement the protective benefits of these diets against the MetS.
Alex’s Notes: Metabolic syndrome (MetS) basically means someone is a basket case of problems waiting to happen. It is harsh but true. For better or worse, environmental factors that interact with MetS include exercise and diet. The focus of the review at hand was to examine three dietary patterns and their components that seem protective against MetS: the Mediterranean diet (MDP), dietary approaches to stop hypertension (DASH) diet, and the Nordic Diet (ND). Studies identified for review included five prospective cohorts and seven randomized clinical trials (RCTs) published from the years 2000-2012.
But first, why these diets? Well, we must begin to move away from nutritionism. As mentioned in a previous article, focusing on dietary patterns rather than single nutrients or food groups is a preferred method of health promotion because foods have synergistic effects that go beyond their individual components. The Western diet is characterized by low vegetable and fruit intake, and high intakes of processed meats and convenience products. The detrimental effects of such a diet go beyond the waist line. Conversely, the MDP as traditionally consumed in Southern Europe is rich with daily intakes of vegetables, fruits, dairy, fish, poultry, nuts, legumes, whole grains, olives, and olive oil. The DASH diet mimics this with high intakes of vegetables, fruits, whole grains, and dairy, and the ND diet traditionally consumed in Northern Europe is based upon fatty fish, dairy, vegetables, fruits, legumes, oats, barely, and almonds. Do you see the difference between these diets and the Western diet that is popular among North America and Australia, and is gaining ground in the Asian-Pacific countries?
So what do these diets have in common that is so beneficial for health? They all focus on “real” food rather than store bought snacks and candies, for one. But ignoring this, they are all rich in insulin sensitizing and anti-inflammatory compounds such as the monounsaturated fatty acids of olives and nuts, omega-3 fatty acids of fish, and fiber and antioxidants of vegetables and fruits. One RCT comparing the MDP to a control “healthy” diet in subjects with MetS found reductions in all inflammatory markers over two years, independent of weight-loss. The DASH diet and ND diet both have clinical trials supporting similar results as well. The consumption of nuts in particular has been shown to be extremely beneficial for reducing MetS risk as well as improving cognition, and dairy is like body armor for health, especially full-fat dairy.
As a super human, none of this should be surprising. Above all, at the risk of being repetitive, the major component of these diets is their focus on real food, and consumption of all the beneficial compounds that come bundled with it. You really are what you eat, so why eat junk?