preventing the global burden of type 2 diabetes by …...maize ugali puerto rico brown rice, beans,...

IntroductionThe prevalence of type 2 diabetes (T2D) has increased rapidly in many countries around the world, as economic growth and urbanization fuel nutrition transitions that promote positive energy balance. A major characteristic of these transitions has been an overall reduction in diet quality due to increasing intake of processed foods, added sugar and refined carbohydrates such as white rice and white wheat flour. Consumption of high-quality carbohydrates, such as whole grains, can reduce the risk of developing T2D by improving blood glucose and insulin levels. In contrast, consumption of refined grains has been associated with an increased risk of T2D. Adopting a diet that is rich in high-quality carbohydrates in place of refined grains could therefore be a cost-effective, feasible, and sustainable approach to T2D prevention, particularly in low- and middle-income countries (LMIC) that have limited resources to manage escalating rates of T2D and other chronic diseases.

• Using culturally appropriate interventions, reduce T2D risk factors by improving diet quality with an emphasis on carbohydrates in Puerto Rico and 12 LMIC’s in Asia, Africa, the Middle East and Latin America.

• Provide evidence to motivate policies and dietary recommendations to reduce the burden of chronic diseases in the study countries and globally.

Conclusion• T2D has become a major public health challenge due to global nutrition transitions promoting unhealthy diets high in refined

carbohydrates, processed foods and added sugars.• Through focus groups and taste tests, GNET researchers have identified culturally acceptable substitution foods to replace

low-quality carbohydrates and have documented barriers and motivators to increasing intake of these high-quality traditional foods.• GNET countries are at varying stages in developing interventions to improve diet quality targeting staple carbohydrate foods as a way

of reducing markers of diabetes risk. • Improving diet quality in LMIC’s could play a key role in diabetes prevention. Global research efforts to identify and promote intake of

culturally- acceptable, high quality staple foods are crucial to combat the growing global diabetes epidemic.

Vasanti Malik,Josiemer Mattei,Hannia Campos,WalterWillett,DonnaSpiegelman,FrankHuandpartnersfrominternationalcollaboratinginstitutions

• Main barriers to brown rice acceptance: lack of awareness of health benefits, texture, palatability, cost and scarcity. Longer cooking time not a major barrier.

• Suggestions to improve acceptance: large-scale promotion of health benefits, subsidies to reduce cost, celebrity endorsement, special recipe advertisements, free samples, mixing with usual food.

Country Substitution FoodsChina Brown rice

India Brown rice (different degrees of refining)Tanzania Brown rice, sorghum ugali, coarse

maize ugaliPuerto Rico Brown rice, beans, high-fiber breakfast

cereal, coconut waterCosta Rica Brown rice, beansKuwait Brown rice, beans, wheat berries, whole

wheat pita breadNigeria Brown rice

• IndiaWorksiteinterventionstudytopreventdiabetes

• BrownricevsWhitericeinterventionstudyonbiomarkersofdiabetesrisk

India

•Effectofpeanutsnackvswhitericesnackbarsonmarkersofdiabetes

•Formativestudyoncafeteriaintervention

China

•Alternatehealthybeveragesamonghighschoolers- FGD

Kuwait

•Glycemicindexvalueofcommonstaplefoods

•Perceptions,barriers/facilitatorsforsubstitutingbrownriceforwhiterice- FGD

Iran

•Brownriceasareplacementforwhitericeinthe3mainethnicgroupsinMalaysia(Indian,MalayandChinese)- FGD

Malaysia

•Glycemicindextestingofbrownriceandwhiterice

•Brownricereplacementforwhiterice- FGD

Nigeria

•BeanintakeandperceptionsaboutbeansinMexico

Mexico

•Formativestudyonworksiteinterventiontoimprovedietquality

Tanzania

•Dietofruraladolescentsandassociatedpsychosocialfactors

CostaRica

•Focusgroupsandtastetestforrice,cerealandbeverages

•Foodfrequencydataondietquality

PuertoRico

•NepalPioneerWorksiteInterventionStudytopreventcardio-metabolicrisk

Nepal

Figure1.2015age-adjustedcomparativeprevalenceofdiabetesinthefourteenGNETcountries/territoriesfortheagegroup20-79

Tanzania4.1%

Kenya2.4%

Nigeria2.3%CostaRica

8.5%

China9.8%

India9.3%

UnitedStates10.8%

Brazil10.4%

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Malaysia17.9%

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Mexico15.8%

Iran10.1%

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Nepal3.7%

PuertoRico12.1%

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Kuwait20.0%

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Preventingtheglobalburdenoftype2diabetesbyimprovingdietquality:theGlobalNutritionandEpidemiologicTransition(GNET)Initiative

Figure2.ThefourphasesofGNETprojects

• 202 adults with diabetes or metabolic syndrome randomly assigned to white rice (WR) or brown rice (BR) group and consumed ad libitum for 16 weeks

• Substituting BR for WR did not lead to substantial improvements in metabolic risk factors

GNET’swebsite: www.hsph.harvard.edu/gnet Contact:ElenaHemler(ehemler@hsph.harvard.edu)

Table1.Findingsfromfocusgroupstudies

DietaryIntervention:Shanghai,China

DataobtainedfromInternationalDiabetesFederation:DiabetesAtlas,2015.

• Suggestion of improvement in HDL in BR compared to WR group (p=0.07)

• Diabetic participants had greater reduction in diastolic blood pressure in BR compared to WR group (p=0.02) and greater reduction in LDL cholesterol in WR compared to BR group (p=0.02)

• Limitations:• Decreased power to detect between group differences

due to improvements in risk factors in both BR and WR groups; Duration of study may be insufficient to detect meaningful changes; Higher proportion of diabetic individuals in WR group; BR group significantly reduced dairy and fruit consumption as well as physical activity, which could have offset benefits of BR

Figure4.ActiveGNETprojects

• More studies with larger sample sizes, longer follow-up duration and different varieties of rice are needed

Figure3.PosterfromarandomizedcrossovertrialsubstitutingbrownriceforwhitericeinIndia

Phase1• Identificationofstaple&alternativefoods

• Focusgroups• Tastetests

Phase2• Selectionofinterventionfoods

• GItestingandContinuousGlucoseMonitoring

Phase3• Interventionstudiesusingbiochemicalmarkers

Phase4• Multicenterclinicaltrialwithdiabetesastheendpoint

GNETInitiativeObjectives