^ Sacks, F. M.; Svetkey, L. P.; Vollmer, W. M.; Appel, L. J.; Bray, G. A.; Harsha, D.; Obarzanek, E.; Conlin, P. R.; Miller, E. R. (2001-01-04). "Effects on blood pressure of reduced dietary sodium and the Dietary Approaches to Stop Hypertension (DASH) diet. DASH-Sodium Collaborative Research Group". The New England Journal of Medicine. 344 (1): 3–10. doi:10.1056/NEJM200101043440101. ISSN 0028-4793. PMID 11136953.
Metabolic syndrome is increasing in prevalence, paralleling an increasing epidemic of obesity. In the United States, where almost two thirds of the population is overweight or obese, more than one fourth of the population meets diagnostic criteria for metabolic syndrome.  In the United States, data from a 1999-2000 survey showed that the age-adjusted prevalence of metabolic syndrome among adults aged 20 years or older had risen from 27% (data from 1988-1994) to 32%. 
^ Feinman, R. D; Pogozelski, W. K; Astrup, A; Bernstein, R. K; Fine, E. J; Westman, E. C; Accurso, A; Frassetto, L; Gower, B. A; McFarlane, S. I; Nielsen, J. V; Krarup, T; Saslow, L; Roth, K. S; Vernon, M. C; Volek, J. S; Wilshire, G. B; Dahlqvist, A; Sundberg, R; Childers, A; Morrison, K; Manninen, A. H; Dashti, H. M; Wood, R. J; Wortman, J; Worm, N (2015). "Dietary carbohydrate restriction as the first approach in diabetes management: Critical review and evidence base". Nutrition. 31 (1): 1–13. doi:10.1016/j.nut.2014.06.011. PMID 25287761.
Metabolic syndrome (also known as metabolic syndrome X) is a grouping of cardiac risk factors that result from insulin resistance (when the body's tissues do not respond normally to insulin). A person with metabolic syndrome has a greatly increased risk of developing type 2 diabetes, cardiovascular disease and premature death. In fact, another name for metabolic syndrome is pre-diabetes. https://www.clairekerslake.com/wp-content/uploads/2011/11/candles.jpg
You are more likely to develop type 2 diabetes if you are age 45 or older, have a family history of diabetes, or are overweight. Physical inactivity, race, and certain health problems such as high blood pressure also affect your chance of developing type 2 diabetes. You are also more likely to develop type 2 diabetes if you have prediabetes or had gestational diabetes when you were pregnant. Learn more about risk factors for type 2 diabetes.
Cataracts and glaucoma are also more common among diabetics. It is also important to note that since the lens of the eye lets water through, if blood sugar concentrations vary a lot, the lens of the eye will shrink and swell with fluid accordingly. As a result, blurry vision is very common in poorly controlled diabetes. Patients are usually discouraged from getting a new eyeglass prescription until their blood sugar is controlled. This allows for a more accurate assessment of what kind of glasses prescription is required.