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By Celez Suratos, MS, RD, ACCN15 Blogger

An individual only needs two things to easily access a myriad of information: a device that has the ability to connect to the internet, and an internet connection. Such information may be as simple as finding nearby show times for a movie, or something more complex, such as trying to self-diagnosis when exhibiting symptoms of a particular disease. This concept is the same when it comes to how the general public may be finding nutrition information. Along with the ease of access of internet searches however, is a high potential of inaccurate or incomplete nutrition information that’s widely distributed.

This can be further exhibited when it comes to myths surrounding carbohydrate (CHO) intake in people with diabetes mellitus (DM). DM is a complex disease in and of itself.Add the ever-evolving nutrition recommendations, such as the diabetic exchange list, glycemic index, and CHO counting into the mix, and one may be more sympathetic as to why a patient may struggle with compliance and management of his or her diabetes.

Alison Evert, MS, RD, CDE from the University of Washington Medical Center approached some of the frequent concerns that arise from patients and healthcare providers when it comes to DM and CHO intake at the 2015 Advances and Controversies in Clinical Nutrition conference. From the presentation and based on a 2005 Dietary Reference Intake report, individuals need to consume at least approximately 139 gram (g) of CHO per day (this does not include creating glucose through pathophysiological processes, such as gluconeogenesis) in order to meet minimum obligatory glucose needs. Ms. Evert reports recent data of median intake of CHO as 220-330 g/day by men and 180-230 g/day by women. Moreover, data from a 2014 National Health and Nutrition Examination Survey (NHANES) reports that adults (20 years and older) without diabetes consume 48 to 50 percent of their daily calories from CHOs. This information tells consumers that intake of CHOs is a necessity, whether or not he or she has DM. It also communicates to nutrition educators that there may not be an ideal percentage of calories that should be consumed from a single macronutrient.

This begs the question, is current and best practice to make percentage recommendations of macronutrient intake based off of total calories, or is this an archaic and irrelevant practice? During her session, Ms. Evert reflected on her time as a dietetic intern in which she made specific calculations on g of CHO a diabetic should consume per day, and passed on a meal plan to patients based on this information. Imagine trying to explain a generic serving recommendation, such as “eat 13 to 17 servings of CHO per day” to an ill and perhaps non-compliant, underserved, or even under-educated patient.

The take-away message Ms. Evert’s presentation is that patients with DM need individualized nutrition recommendations/meals plans, particularly as there are major differences in type 1 versus type 2 DM, the spectrum of type 2 DM progression among patients, and medications that affect glycemic control. Her suggestion – make it a point to discuss what our food sources of CHO are and focus on lifestyle behavior change.

By: Emma Partridge, MS Candidate

Green tea contains a high concentration of polyphenols, most of which are flavanols. Flavanols are commonly known as catechins, the most active catechin being epigallocatechin-3-gallate (EGCG).1 Within the world of nutrition, green tea is consistently touted as a beverage with a plethora of health benefits. These benefits are far-reaching and specific roles of green tea have been identified to improve symptoms or reverse disease damage amongst people with autoimmune disease, heart disease, cancer, liver disorders, smoking complications, chronic inflammation, and more. The roles of green tea often overlap and while green tea consumption is important for those with various diseases, the consumption of green tea by healthy individuals may be integral in the prevention of many of the following diseases.

Chronic Inflammatory Disease
EGCG may be most important flavanol when it comes to inflammation control.2 EGCG has been shown to suppress the production of cytokines, pro-inflammatory mediators. Suppressing cytokines decreases long-term inflammation and has been shown to improve inflammation-related symptoms in arthritis models.3,4

Autoimmune Disease
In addition to helping to control the chronic inflammation associated with most autoimmune diseases, EGCG has been shown to suppress auto-reactive T cell proliferation. Auto-reactive T cells act against the body, resulting in various forms of autoimmune diseases. EGCG may also help to regulate T-helper cell balance, which may decrease the pathogenesis of arthritic diseases, especially rheumatoid arthritis.3

Type 2 Diabetes Risk
Type 2 Diabetes is sweeping America, and food production practices, availability, and affordability are making it harder for people to access healthy options. The ease of accessing and affording unhealthy foods is increasing the risk of diabetes among populations. Green tea, as well as coffee, has been associated with lowering the risk of type 2 diabetes, though the mechanism is unknown and the data inconsistent. However, in a study of 40,000+ people followed for 10 years, researchers found that daily consumption of at least three cups of coffee or tea may lower type 2 diabetes risk.5

Heart Disease & Stroke Risk
In an article published by the American Heart Association, researchers found that people who drank two to three cups of green tea per day had a 14% lower risk of stoke.6 The research on green tea and stroke risk comes on the wake of multiple studies finding links between green tea and heart health. Multiple studies found green tea consumption to lower risk of death from heart attacks by 26% and lower risk of coronary artery disease by 28%.7

Cancer & Tumor Growth
Cancer is a leading cause of death in the United States, behind heart disease. Green tea has already been shown to be beneficial in preventing the leading cause of death; now studies have now shown that the EGCG may affect transformed cells by inhibiting the growth of certain cell lines, inducing apoptosis, and altering gene expression to prevent transformed cells from becoming cancerous.8

Smoking
The polyphenols in green tea have shown to work against carcinogens, while the antioxidant effects may reverse endothelial dysfunction in healthy smokers.8 The reversal of endothelial dysfunction in smokers is important because it plays a role in the pathogenesis of atherosclerosis and cardiovascular disease.9

Liver Disease
Green tea’s aforementioned anti-carcinogenic affect may play a role in preventing liver disease. Active polyphenols detoxify reactive oxygen species, preventing oxygen free radicals from destroying hepatocytes and causing oxidative DNA damage. Multiple studies have shown that, most likely via this method, green tea intake can attenuate liver disease or liver cancer.10

Weight Loss & Weight Maintenance
Green tea’s affect on weight loss may be attributed to two components: EGCG and caffeine. Caffeine alone does play some role in increasing energy expenditure, but when combined with EGCG, the mixture stimulates energy expenditure and fat oxidation to a greater degree. This may trigger weight loss, and additional evidence reveals that continual green tea consumption can further help to maintain weight.11

In determining whether or not green tea is for you, the answer is likely yes. While there are risks by way of overconsumption, a few glasses a day has been shown to be beneficial for the all-around healthy person in preventing disease and for the person suffering from various diseases or ailments.

1.Ehrlich SD. Green Tea. 2011; http://umm.edu/health/medical/altmed/herb/green-tea.
2.Hamer M. The beneficial effects of tea on immune function and inflammation: a review of evidence from in vitro, animal, and human research. Nutrition Research. 2007;27(7):373-379.
3.Wu DY, Wang JP, Pae M, Meydani SN. Green tea EGCG, T cells, and T cell-mediated autoimmune diseases. Molecular Aspects of Medicine. 2012;33(1):107-118.
4.Kim HR, Rajaiah R, Wu QL, et al. Green Tea Protects Rats against Autoimmune Arthritis by Modulating Disease-Related Immune Events. Journal of Nutrition. 2008;138(11):2111-2116.
5.van Dieren S, Uiterwaal C, van der Schouw YT, et al. Coffee and tea consumption and risk of type 2 diabetes. Diabetologia. 2009;52(12):2561-2569.
6.Green tea, coffee may help lower stroke risk. 2013; http://newsroom.heart.org/news/green-tea-coffee-may-help-lower-stroke-risk.
7.Green tea may lower heart disease risk. Harvard Heart Letter 2012; http://www.health.harvard.edu/heart-health/green-tea-may-lower-heart-disease-risk.
8.Chen ZP, Schell JB, Ho CT, Chen KY. Green tea epigallocatechin gallate shows a pronounced growth inhibitory effect on cancerous cells but not on their normal counterparts. Cancer Letters. 1998;129(2):173-179.
9.Nagaya N, Yamamoto H, Uematsu M, et al. Green tea reverses endothelial dysfunction in healthy smokers. Heart. 2004;90(12):1485-1486.
10.Jin X, Zheng R-h, Li Y-m. Green tea consumption and liver disease: a systematic review. Liver International. 2008;28(7):990-996.
11.Hursel R, Viechtbauer W, Westerterp-Plantenga MS. The effects of green tea on weight loss and weight maintenance: a meta-analysis. International Journal of Obesity. 2009;33(9):956-961.

By Banaz Al-khalidi

November is National Diabetes Month and World Diabetes Day takes place yearly on November 14 to engage millions of people worldwide in diabetes advocacy and awareness. The International Diabetes Federation estimates that 382 million adults (20-79 years old) suffered from diabetes in 2013, which equates to a prevalence of 8.3%. To provide a better perspective by nation, the 10 countries with the highest prevalence of diabetes in 2013 were as follows: Tokelau (37.5%), Federated States of Micronesia (35%), Marshall Islands (34.9%), Kiribati (28.8%), Cook Islands (25.7%), Vanuatu (24%), Saudi Arabia (24%), Nauru (23.3%), Kuwait (23.1%), and Qatar (22.9%). However, if we were to look at the 3 countries with the greatest number of people with diabetes, China ranks the highest (98.4 million), followed by India (65.1 million) and USA (24.4 million). These figures are quite alarming.

Of those suffering from diabetes, type 2 diabetes comprises almost 90% of people with diabetes around the world. As such, type 2 diabetes is one of the fastest growing health problems in the world. So what could be driving this epidemic?

Evidence from observational studies have consistently shown us that low blood levels of vitamin D are associated with an increased risk of type 2 diabetes. The results of numerous observational studies led to speculation that the development of type 2 diabetes is associated with vitamin D insufficiency. Going back to the figures presented earlier, if vitamin D insufficiency is a risk factor for type 2 diabetes, one might also speculate that countries with higher prevalence of diabetes are facing a coexisting problem of type 2 diabetes and vitamin D insufficiency. For example, Tokelauans (the nationals of Tokelau) who have the highest prevalence of type 2 diabetes, may also be at risk for vitamin D insufficiency despite having a tropical and marine climate. The question then becomes, could vitamin D be a causal factor in the development of type 2 diabetes? While this might sound too simplistic, I assure you it’s not.

Interpretation of evidence on vitamin D and type 2 diabetes is complicated for a number of reasons. First and foremost, observational studies do not tell us anything about the cause-effect relationship between vitamin D and type 2 diabetes because of possible uncontrolled confounding factors, such as physical activity, that may affect both vitamin D levels and the risk of type 2 diabetes. Second, observational studies cannot inform us about reverse causation. In other words, which comes first, the chicken or the egg? Third, there are a myriad of factors that affect vitamin D levels, including environmental, cultural, genetic and physiological factors. It remains unclear then whether there is a causal link between vitamin D and type 2 diabetes.

To answer this question, a large genetic study published in The Lancet Diabetes and Endocrinology journal looked at the causal association between low blood levels of vitamin D and risk of type 2 diabetes. The study concluded that the association between vitamin D and type 2 diabetes is unlikely to be causal. The research, which was a Mendelian randomization study, examined the link between type 2 diabetes risk and vitamin D, by assessing the genes that control blood levels of vitamin D. Most importantly, the design of this study has a powerful control for confounding factors and reverse causation which are issues of concern in observational studies. This may partly explain the discrepancy between results from earlier observational studies and this study in question. However, we still need to be cautious about interpreting the results from mendelian randomization studies as some of the underlying assumptions in the study might remain untested.

The take home message is that no special recommendations could be made about vitamin D levels or supplementation for people with type 2 diabetes. However, long-term randomized trials of vitamin D supplementation remain important to elucidate vitamin D’s role in type 2 diabetes.

As we recognize National Diabetes Awareness this month, it is important to remind patients that diabetes is a progressive chronic lifestyle disease that can be controlled by making healthy lifestyle changes- such as partaking in regular physical activity, eating a balanced diet, maintaining a healthy body weight, taking prescribed medications, joining a smoking cessation program, and improving sleeping patterns.

Reference
Zheng Ye, Stephen J Sharp, Stephen Burgess, Robert A Scott, Fumiaki Imamura, Claudia Langenberg, Nicholas J Wareham, Nita G Forouhi. Association between circulating 25-hydroxyvitamin D and incident type 2 diabetes: a mendelian randomisation study. The Lancet Diabetes & Endocrinology, 2014; DOI: 10.1016/S2213-8587(14)70184-6.