The potential benefits of fiber in metabolic syndrome relate to two proposed mechanisms. Insoluble fibers absorb and retain water in the gastrointestinal tract, leading to a feeling of satiety and potential weight loss. 

Monounsaturated fats

Monounsaturated fats have been shown to decrease LDL and increase HDL cholesterol, as well as decrease serum triglycerides. They are found in almonds, cashews, hazelnuts, macadamia nuts, peanuts, and pistachios, as well as avocados, canola oil, sesame oil, grapeseed oil, and high-oleic safflower oil. 

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Polyunsaturated fatty acids

Omega-3 (fish oils, flaxseed) and omega-6 (vegetable oils) are the main dietary polyunsaturated fatty acids. Omega-3 fatty acids are considered to reduce inflammation, whereas omega-6 fatty acids tend to increase inflammation. This is one of the theorized benefits of the Mediterranean diet, promoting “a healthier balance” in the ratio of omega-3 fatty acids to omega-6 fatty acids (Table 2).

TABLE 2. Simple approaches that may be beneficial for metabolic syndrome

Weight loss Target BMI of 19–25
Exercise Aerobic and weight/resistance training
Limit sugar and simple carbohydrates Substitute with vegetables, beans, and low glycemic fruits such as berries
Emphasize monounsaturated fats Olive, avocado, and canola oils, and nuts such as
Increase fiber Particularly helpful: eggplant, oat products, and supplements containing psyllium (Metamucil, Konsyl, and others)
Omega-3 fatty acids Most effective: fatty fish two or three times weekly; salmon, anchovies, sardines, or fish oil supplements (Nordic Naturals Omega-3, New Chapter Wholemega, and many others)


The prevalence of metabolic syndrome and the toll that it is exacting on the health of our patients warrants all clinicians to not accept the status quo and to find the best way to help our patients make meaningful progress in reducing the prevalence and impact of this common problem.

Thomas Duncan, MD, is in private practice in North Carolina.


  1. Scholze J, Alegria E, Ferri C, et al. Epidemiological and economic burden of metabolic syndrome and its consequences in patients with hypertension in Germany, Spain, and Italy: a prevalence-based model. BMC Public Health. 2010;10:529.

  2. Grundy SM, Brewer HB Jr, Cleeman JI, et al. Definition of metabolic syndrome. Report of the National Heart, Lung, and Blood Institute/American Heart Association conference on scientific issues related to definition. Circulation. 2004;109(3):433-438.

  3. Estruch R, Ros E, Salas-Salvado J, et al. Primary prevention of cardiovascular disease with a Mediterranean diet. N Engl J Med. 2013;368(14):1279-1290.

  4. Sacks FM, Svetkey LP, Vollmer WM, et al. Effects on blood pressure of reduced dietary sodium and the Dietary Approaches to Stop Hypertension (DASH) diet. DASH-Sodium Collaborative Research Group. N Engl J Med. 2001;344(1):3-10 

  5. Smith MM, Trexler ET, Sommer AJ, et al. Unrestricted paleolithic diet is associated with unfavorable changes to blood lipids in healthy subjects. Int J Exerc Sci. 2014;7(2):128-139.