In the United States, children are becoming obese at triple the rate compared with the 1960s, making the study and treatment of this problem paramount. The epidemic of metabolic syndrome in children and adolescents is an international phenomenon, leading the International Diabetes Foundation to publish an updated consensus statement to guide diagnosis and further study of the condition. [51, 52]
Epigenetic phenomena, such as DNA methylation and histone modification, have also been implicated in the pathogenesis of hypertension. For example, a high-salt diet appears to unmask nephron development caused by methylation. Maternal water deprivation and protein restriction during pregnancy increase renin-angiotensin expression in the fetus. Mental stress induces a DNA methylase, which enhances autonomic responsiveness. The pattern of serine protease inhibitor gene methylation predicts preeclampsia in pregnant women. 
Insulin is released into the blood by beta cells (β-cells), found in the islets of Langerhans in the pancreas, in response to rising levels of blood glucose, typically after eating. Insulin is used by about two-thirds of the body's cells to absorb glucose from the blood for use as fuel, for conversion to other needed molecules, or for storage. Lower glucose levels result in decreased insulin release from the beta cells and in the breakdown of glycogen to glucose. This process is mainly controlled by the hormone glucagon, which acts in the opposite manner to insulin.
Fortunately, since peaking in 2001-2002, the overall prevalence of metabolic syndrome in the United States has fallen, primarily due to decreases in the prevalences of hypertriglyceridemia and hypertension—and in spite of increases in the prevalences of hyperglycemia and obesity/waist circumference.  Data from the 2009-2010 National Health and Nutrition Examination Survey (NHANES) showed that the age-adjusted prevalence of metabolic syndrome had fallen to approximately 24% in men and 22% in women. 
^ Brunner EJ, Hemingway H, Walker BR, Page M, Clarke P, Juneja M, Shipley MJ, Kumari M, Andrew R, Seckl JR, Papadopoulos A, Checkley S, Rumley A, Lowe GD, Stansfeld SA, Marmot MG (November 2002). "Adrenocortical, autonomic, and inflammatory causes of the metabolic syndrome: nested case-control study". Circulation. 106 (21): 2659–65. doi:10.1161/01.cir.0000038364.26310.bd. PMID 12438290.
Even the low-fat craze that kicked off in the late 1970s–which was based on the intuitively appealing but incorrect notion that eating fat will make you fat–depended on the calorie-counting model of weight loss. (Since fatty foods are more calorie-dense than, say, plants, logic suggests that if you eat less of them, you will consume fewer calories overall, and then you’ll lose weight.)
Metabolic syndrome is a serious health condition that affects about 23 percent of adults and places them at higher risk of cardiovascular disease, diabetes, stroke and diseases related to fatty buildups in artery walls. The underlying causes of metabolic syndrome include overweight and obesity, physical inactivity, genetic factors and getting older.
^ Emadian A, Andrews RC, England CY, Wallace V, Thompson JL (November 2015). "The effect of macronutrients on glycaemic control: a systematic review of dietary randomised controlled trials in overweight and obese adults with type 2 diabetes in which there was no difference in weight loss between treatment groups". The British Journal of Nutrition. 114 (10): 1656–66. doi:10.1017/S0007114515003475. PMC 4657029. PMID 26411958.
The fact that the diagnostic criteria for metabolic syndrome vary between ethnic populations is testimony to significant nuances in the manifestation of metabolic syndrome in these groups. The original metabolic syndrome criteria were derived in mostly Caucasian populations, and some have argued for modification of individual criteria for specific ethnic subgroups, as has been done with waist circumference for patients of Asian origin. 
^ 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.
Glucose is a simple sugar found in food. Glucose is an essential nutrient that provides energy for the proper functioning of the body cells. Carbohydrates are broken down in the small intestine and the glucose in digested food is then absorbed by the intestinal cells into the bloodstream, and is carried by the bloodstream to all the cells in the body where it is utilized. However, glucose cannot enter the cells alone and needs insulin to aid in its transport into the cells. Without insulin, the cells become starved of glucose energy despite the presence of abundant glucose in the bloodstream. In certain types of diabetes, the cells' inability to utilize glucose gives rise to the ironic situation of "starvation in the midst of plenty". The abundant, unutilized glucose is wastefully excreted in the urine.
The term "diabetes" or "to pass through" was first used in 230 BCE by the Greek Apollonius of Memphis. The disease was considered rare during the time of the Roman empire, with Galen commenting he had only seen two cases during his career. This is possibly due to the diet and lifestyle of the ancients, or because the clinical symptoms were observed during the advanced stage of the disease. Galen named the disease "diarrhea of the urine" (diarrhea urinosa).
Hypertension develops secondary to environmental factors, as well as multiple genes, whose inheritance appears to be complex. [12, 21] Furthermore, obesity, diabetes, and heart disease also have genetic components and contribute to hypertension. Epidemiological studies using twin data and data from Framingham Heart Study families reveal that BP has a substantial heritable component, ranging from 33-57%. [22, 23, 24]
Despite these genetic findings, targeted genetic therapy seems to have little impact on hypertension. In the general population, not only does it appear that individual and joint genetic mutations have very small effects on BP levels, but it has not been shown that any of these genetic abnormalities are responsible for any applicable percentage of cases of hypertension in the general population. 
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Dr Jacomien de Villiers qualified as a specialist physician at the University of Pretoria in 1995. She worked at various clinics at the Department of Internal Medicine, Steve Biko Hospital, these include General Internal Medicine, Hypertension, Diabetes and Cardiology. She has run a private practice since 2001, as well as a consultant post at the Endocrine Clinic of Steve Biko Hospital.