kelingwang/causation_strength_rating huggingface dataset:
The locations of Medicare DPPs are available online at innovation.cms.gov/innovation-models/medicare-diabetes-prevention-program/mdpp-map.
To qualify for Medicare coverage, individuals must have BMI >25 kg/m2 (or BMI >23 kg/m2 if self-identified as Asian) and glycemic testing consistent with prediabetes in the last year.
Medicaid coverage of the National DPP is also expanding on a state-by-state basis.
While CDC-recognized behavioral counseling programs, including Medicare DPP services, have met minimum quality standards and are reimbursed by many payers, lower retention rates have been reported for younger adults and racial and ethnic minority populations (46).
Therefore, other programs and modalities of behavioral counseling for diabetes prevention may also be appropriate and efficacious based on individual preferences and availability.
The use of community health workers to support DPP-like interventions has been shown to be effective and cost-effective (47,48) (see Section 1, �Improving Care and Promoting Health in Populations,� for more information).
The use of community health workers may facilitate the adoption of behavior changes for diabetes prevention while bridging barriers related to social determinants of health.
However, coverage by third-party payers remains limited.
Counseling by a registered dietitian nutritionist (RDN) has been shown to help individuals with prediabetes improve eating habits, increase physical activity, and achieve 7–10% weight loss (13,49–51).
Individualized medical nutrition therapy (see Section 5, �Facilitating Positive Health Behaviors and Well-being to Improve Health Outcomes,� for more detailed information) is also effective in improving glycemia in individuals diagnosed with prediabetes (26,49).
Furthermore, trials involving medical nutrition therapy for adults with prediabetes found significant reductions in weight, waist circumference, and glycemia.
Individuals with prediabetes can benefit from referral to an RDN for individualized medical nutrition therapy upon diagnosis and at regular intervals throughout their treatment plan (50,52).
Other health care professionals, such as pharmacists and diabetes care and education specialists, may be considered for diabetes prevention efforts (53,54).
Technology-assisted programs may effectively deliver a DPP-like intervention (55–60).
A digital diabetes prevention program improved cardiovascular risk at 4 months but not at 12 months (61).
Such technology-assisted programs may deliver content through smartphones, web-based applications, and telehealth and may be an acceptable and efficacious option to bridge barriers, particularly for individuals with low income and people in rural locations; however, not all technology-assisted programs are effective (55,62–64).
The CDC Diabetes Prevention Recognition Program (DPRP) (cdc.gov/diabetes/prevention/requirements-recognition.htm) certifies technology-assisted modalities as effective vehicles for DPP-based interventions; such programs must use an approved curriculum, include interaction with a coach, and attain the DPP outcomes of participation, physical activity reporting, and weight loss.
Health care professionals should consider referring adults with prediabetes to certified technology-assisted programs.
People with prediabetes often have other cardiovascular risk factors, including hypertension and dyslipidemia (100), and are at increased risk for cardiovascular disease (101,102).
Evaluation for tobacco use and referral for tobacco cessation should be part of routine care for those at risk for diabetes.
Of note, the years immediately following smoking cessation may represent a time of increased risk for diabetes (103–105), and individuals should be monitored for diabetes development and receive evidence-based lifestyle behavior change for diabetes prevention described in this section.
See Section 5, �Facilitating Positive Health Behaviors and Well-being to Improve Health Outcomes,� for more detailed information.
The lifestyle interventions for weight loss in study populations at risk for type 2 diabetes have shown a reduction in cardiovascular risk factors and the need for medications used to treat these cardiovascular risk factors (106,107).
The lifestyle intervention in the Da Qing study was associated with lowering cardiovascular disease and mortality at 23 and 30 years of observational follow-up (6,8).
Treatment goals and therapies for hypertension and dyslipidemia in the primary and secondary prevention of cardiovascular disease for people with prediabetes should be based on their level of cardiovascular risk.
Increased vigilance is warranted to identify and treat these and other cardiovascular diseases risk factors (108).
The overall objectives of DSMES are to support informed decision-making, self-care behaviors, problem-solving, and active collaboration with the health care team to improve clinical outcomes, health status, and well-being in a cost-effective manner (2).
DSMES services facilitate the knowledge, decision-making, and skills mastery necessary for optimal diabetes self-care and incorporate the needs, goals, and life experiences of the person with diabetes.
Health care professionals are encouraged to consider the burden of treatment (9) and the person�s level of confidence and self-efficacy for management behaviors as well as the level of social and family support when providing DSMES.
An individual�s engagement in self-management behaviors and the effects on clinical outcomes, health status, and quality of life, as well as the psychosocial factors impacting the person�s ability to self-manage, should be monitored as part of routine clinical care.
A randomized controlled trial (RCT) testing a decision-making education and skill-building program (10) showed that addressing these targets improved health outcomes in a population in need of health care resources.
Furthermore, following a DSMES curriculum improves quality of care (11).
As the use of judgmental words is associated with increased feelings of shame and guilt, health care professionals are encouraged to consider the impact that language has on building therapeutic relationships and should choose positive, strength-based words and phrases that put people first (4,12).
Please see Section 4, �Comprehensive Medical Evaluation and Assessment of Comorbidities,� for more on use of language.
In accordance with the national standards for DSMES (13), all people with diabetes should participate in DSMES, as it helps people with diabetes to identify and implement effective self-management strategies and cope with diabetes (2).
Ongoing DSMES helps people with diabetes to maintain effective self-management throughout the life course as they encounter new challenges and as advances in treatment become available (14).
Management and reduction of weight is important for people with type 1 diabetes, type 2 diabetes, or prediabetes with overweight or obesity.
To support weight loss and improve A1C, cardiovascular disease (CVD) risk factors, and well-being in adults with overweight/obesity and prediabetes or diabetes, MNT and DSMES services should include an individualized eating plan in a format that results in an energy deficit in combination with enhanced physical activity (73).
Lifestyle intervention programs should be intensive and have frequent follow-up to achieve significant reductions in excess body weight and improve clinical indicators.
Behavior modification targets include physical activity, calorie restriction, weight management strategies, and motivation.
There is strong and consistent evidence that modest, sustained weight loss can delay the progression from prediabetes to type 2 diabetes (103,105,106) (see Section 3, �Prevention or Delay of Diabetes and Associated Comorbidities�) and is beneficial for the management of type 2 diabetes (see Section 8, �Obesity and Weight Management for the Prevention and Treatment of Type 2 Diabetes�).
In prediabetes, the weight loss goal is 5–7% or higher for reducing risk of progression to type 2 diabetes (107).
In conjunction with support for healthy lifestyle behaviors, medication-assisted weight loss can be considered for people at risk for type 2 diabetes when needed to achieve and sustain 7–10% weight loss (108,109) (see Section 8, �Obesity and Weight Management for the Prevention and Treatment of Type 2 Diabetes�).
People with prediabetes at a healthy weight should also be considered for behavioral interventions to help establish routine aerobic and resistance exercise (107,110,111) as well as to establish healthy eating patterns.
Services delivered by health care professionals familiar with diabetes and its management, such as an RDN, have been found to be effective (102).
For many individuals with overweight and obesity with type 2 diabetes, 5% weight loss is needed to achieve beneficial outcomes in glycemic control, lipids, and blood pressure (112,113).
It should be noted, however, that the clinical benefits of weight loss are progressive, and more intensive weight loss goals (i.e., 15%) may be appropriate to maximize benefit depending on need, feasibility, and safety (114,115).
Long-term durability of weight loss remains a challenge; however, newer medications (beyond metabolic surgery) may have potential for sustainability, impact on cardiovascular outcomes, and weight reduction beyond 10–15% (116–120).
In select individuals with type 2 diabetes, an overall healthy eating plan that results in energy deficit in conjunction with weight loss medications and/or metabolic surgery should be considered to help achieve weight loss and maintenance goals, lower A1C, and reduce CVD risk (108,121,122).
Overweight and obesity are also increasingly prevalent in people with type 1 diabetes and present clinical challenges regarding diabetes treatment and CVD risk factors (123,124).
Sustaining weight loss can be challenging (112,125) but has long-term benefits; maintaining weight loss for 5 years is associated with sustained improvements in A1C and lipid levels (126).
MNT guidance from an RDN with expertise in diabetes and weight management throughout the course of a structured weight loss plan is strongly recommended.
Studies have demonstrated that a variety of eating plans, varying in macronutrient composition, can be used effectively and safely in the short term (1–2 years) to achieve weight loss in people with diabetes.
These plans include structured low-calorie meal plans with meal replacements (114,126,128), a Mediterranean eating pattern (129), and low-carbohydrate meal plans with additional support (130,131).
However, no single approach has been proven to be consistently superior (73,132–134), and more data are needed to identify and validate those meal plans that are optimal with respect to long-term outcomes and acceptability.
Any approach to meal planning should be individualized, considering the health status, personal and cultural preferences, health goals, ability to sustain the recommendations, and ultimately food access and nutrition security (73).
Evidence suggests that there is not an ideal percentage of calories from carbohydrate, protein, and fat for people with diabetes.
Therefore, macronutrient distribution should be based on an individualized assessment of current eating patterns, preferences, and metabolic goals.
Members of the health care team should complement MNT by providing evidence-based guidance that helps people with diabetes make healthy food choices that meet their individualized needs and improve overall health.
Research confirms that a variety of eating patterns are acceptable for the management of diabetes (73,104,141,142).
Until the evidence around benefits of different eating patterns is strengthened, health care professionals should focus on the core dimensions common among patterns: inclusion of nonstarchy vegetables, whole fruits, legumes, whole grains, nuts, seeds, and low-fat dairy products and minimizing consumption of meat, sugar-sweetened beverages, sweets, refined grains, and ultraprocessed foods (143,144).
Evidence for eating patterns has been informed by RCTs, prospective cohort studies, systematic reviews, and network meta-analysis.
Those most frequently referenced include Mediterranean, DASH, low-fat, carbohydrate-restricted, vegetarian, and vegan eating patterns.
As stated previously, there is insufficient evidence to select one over the other (137,141,142,145–154).
Ultimately, ongoing diabetes and nutrition education paired with appropriate support to implement and sustain health behaviors is recommended (103).
Referral to and ongoing support from an RDN is essential to assess the overall nutrition status of, and to work collaboratively with, the person with diabetes to create a personalized meal plan that coordinates and aligns with the overall lifestyle treatment plan, including physical activity and medication use.
Using shared decision-making to collaboratively select a method for how to execute the plan may be part of the nutrition care process.
Few head-to-head studies have compared different dietary approaches.
In a systematic review and meta-analysis of carbohydrate counting versus other forms of dietary advice (standard education, low glycemic index, and fixed carbohydrate quantities), no significant differences were seen in A1C levels compared with standard education (145).
In another RCT, a simplified carbohydrate counting tool based on individual glycemic response was noninferior to conventional carbohydrate counting in 85 adults with type 1 diabetes (146).
In a randomized crossover trial, carbohydrate counting and qualitative meal size (low, medium, and high carbohydrate) were compared.
Time in range was 74% for carbohydrate counting and 70.5% for the quantitative meal size estimates.
Noninferiority was not confirmed for the qualitative method (147).
Newer technologies (smart phone apps and CGM), including automated insulin delivery, may decrease the need for precise carbohydrate counting and allow for personalized nutrition approaches (148,149).
An RCT found that two meal-planning approaches (diabetes plate method and carbohydrate counting) were effective in helping achieve improved A1C (150).
The diabetes plate method is a commonly used visual approach for providing basic meal planning guidance in type 1 and type 2 diabetes.
This simple graphic (featuring a 9-inch plate) shows how to portion foods (one-half of the plate for nonstarchy vegetables, one-quarter of the plate for protein, and one-quarter of the plate for carbohydrates).
Carbohydrate counting is a more advanced skill that helps plan for and track how much carbohydrate is consumed at meals and snacks.
Meal planning approaches should be customized to the individual, including their numeracy (150) and food literacy level.
Health numeracy refers to understanding and using numbers and numerical concepts in relation to health and self-management (155).
Food literacy generally describes proficiency in food-related knowledge and skills that ultimately impact health, although specific definitions vary across initiatives (151,152).
Intermittent fasting or time-restricted eating as strategies for weight and glucose management have been studied and have gained popularity.
Intermittent fasting is an umbrella term that includes three main forms of restricted eating: alternate-day fasting (energy restriction of 500–600 calories on alternate days), the 5:2 diet (energy restriction of 500–600 calories on consecutive or nonconsecutive days with usual intake the other five), and time-restricted eating (daily calorie restriction based on window of time of 8–15 h).
Each produces mild to moderate weight loss (3–8% loss from baseline) over short durations (8–12 weeks) with no significant differences in weight loss when compared with continuous calorie restriction (153,154,156,157).
A few studies have extended up to 52 weeks and show similar findings (158–162) with diverse populations.
Generally, time-restricted eating or shortening the eating window can be adapted to any eating pattern and has been shown to be safe for adults with type 1 or type 2 diabetes (161).
People with diabetes who are on insulin and/or secretagogues should be medically monitored during the fasting period (163).
Because of the simplicity of intermittent fasting and time-restricted eating, these may be useful strategies for people with diabetes who are looking for practical eating management tools.
Use of partial meal replacements or total meal replacements is an additional tool or strategy for energy restriction.
Meal replacements are prepackaged foods (bars, shakes, and soups) that contain a fixed amount of macroutrients and micronutrients.
They have been shown to improve nutrient quality and glycemic management and to reduce portion size and consequent energy intake.
In a meta-analysis involving 17 studies incorporating both partial and total meal replacements, greater weight loss and improvement in A1C and fasting blood glucose were demonstrated compared with conventional diets (164).
Meal replacements have been used in several landmark clinical trials, including Look AHEAD (Action for Health in Diabetes) (165), DiRECT (Diabetes Remission Clinical Trial) (166), and PREVIEW (Prevention of Diabetes Through Lifestyle Intervention and Population Studies in Europe and Around the World) (167), showing partial or total meal replacements can be a potential short-term strategy for weight loss.
Regardless of the eating pattern, meal plan, and/or dietary approach selected, long-term follow-up and support from members of the diabetes care team are needed to optimize self-efficacy and maintain behavioral changes (140).
Chrononutrition is a growing and emerging specialty in the field of nutrition and biology that tries to understand how the timing of food ingestion affects metabolic health (168).
Glucose metabolism follows a circadian rhythm through diurnal variation of glucose tolerance, peaking during daylight hours when food is consumed.
Some preliminary studies show cardiometabolic benefits when food is consumed earlier (169).
Similarly, circadian disruptions found in shift workers increase risk of type 2 diabetes (170).
Although more research needs to be done, this evolving area of research may show promise to improve glucose regulation.
Although intermittent fasting and time-restricted eating are specific dietary strategies for energy restriction, religious fasting has been practiced for thousands of years and is part of many faith-based traditions.
Duration, frequency, and type of fast vary among different religions (171).
For example, Jewish people abstain from any intake for ~24 h during Yom Kippur (172,173).
For Muslims, Ramadan fasting lasts for a full month, when abstinence from any food or drink is required from dawn to dusk (174).
Individuals with diabetes who fast have an increased risk for hypoglycemia, dehydration, hyperglycemia, and ketoacidosis.
Risk can vary depending on the type of diabetes, type of therapy, and presence and severity of diabetes-related complications (175).
Health care professionals, including RDNs, certified DCES, and others, should inquire about any religious fasting for people with diabetes and provide education and support to accommodate their choice.
Education regarding glucose checking, medication/fluid adjustment, timing and intensity of physical activity, and meal choices pre- and post-fast should be provided (176).
Treatment pre- and post-fast should be culturally sensitive and individualized (177).
Specific recommendations for diabetes management during Ramadan (175) and Yom Kippur (172) are available.
Carbohydrates
Studies examining the optimal amount of carbohydrate intake for people with diabetes are inconclusive, although monitoring carbohydrate intake is a key strategy in reaching glucose goals in people with type 1 and type 2 diabetes (178,179).
For people with type 2 diabetes, low-carbohydrate and very-low-carbohydrate eating patterns in particular have been found to reduce A1C and the need for antihyperglycemic medications (139,180–184).
Systematic reviews and meta-analyses of RCTs found carbohydrate-restricted eating patterns, particularly those considered low carbohydrate (<26% total energy), were effective in reducing A1C in the short term (<6 months), with less difference in eating patterns beyond 1 year (134,182,185–187).
Questions still remain about the optimal degree of carbohydrate restriction and the long-term effects of those meal patterns on CVD.
A systematic review and meta-analysis of RCTs investigating the dose-dependent effects of carbohydrate restriction found each 10% decrease in carbohydrate intake had reductions in levels of A1C, fasting plasma glucose, body weight, lipids, and systolic blood pressure at 6 months, but favorable effects diminished and were not maintained at follow-up or at greater than 12 months.
This systematic review highlights the metabolic complexity of response to dietary intervention in type 2 diabetes as well as the need to better understand longer-term sustainability and results (188).
Part of the challenge in interpreting low-carbohydrate research has been due to the wide range of definitions for a low-carbohydrate eating plan (189,190).
Weight reduction was also a goal in many low-carbohydrate studies, which further complicates evaluating the distinct contribution of the eating pattern (48,130,134,188).
As studies on low-carbohydrate eating plans generally indicate challenges with long-term sustainability (180), it is important to reassess and individualize meal plan guidance regularly for those interested in this approach.
Health care professionals should maintain consistent medical oversight and recognize that insulin and other diabetes medications may need to be adjusted to prevent hypoglycemia, and blood pressure will need to be monitored.
In addition, very-low-carbohydrate eating plans are not currently recommended for individuals who are pregnant or lactating, children, people who have renal disease, or people with or at risk for disordered eating, and these plans should be used with caution in those taking sodium�glucose cotransporter 2 inhibitors because of the potential risk of ketoacidosis (191–193).
Regardless of the amount of carbohydrate in the meal plan, focus should be placed on high-quality, nutrient-dense carbohydrate sources that are high in fiber and minimally processed.
The addition of dietary fiber modulates composition of gut microbiota and increases gut microbial diversity.
Although there is still much to be elucidated with the gut microbiome and chronic disease, higher-fiber diets are advantageous (194).
Both children and adults with diabetes are encouraged to minimize intake of refined carbohydrates with added sugars, fat, and sodium and instead focus on carbohydrates from vegetables, legumes, fruits, dairy (milk and yogurt), and whole grains.
People with diabetes and those at risk for diabetes are encouraged to consume a minimum of 14 g of fiber/1,000 kcal, with at least half of grain consumption being whole, intact grains, according to the Dietary Guidelines for Americans (98).
Regular intake of sufficient dietary fiber is associated with lower all-cause mortality in people with diabetes (195,196), and prospective cohort studies have found dietary fiber intake is inversely associated with risk of type 2 diabetes (197–199).
The consumption of sugar-sweetened beverages and processed food products with large amounts of refined grains and added sugars is strongly discouraged (98,200,201), as these have the capacity to displace healthier, more nutrient-dense food choices.
The literature concerning glycemic index and glycemic load in individuals with diabetes is complex, often with varying definitions of low- and high-glycemic-index foods (202,203).
The glycemic index ranks carbohydrate foods on their postprandial glycemic response, and glycemic load takes into account both the glycemic index of foods and the amount of carbohydrate eaten.
Studies have found mixed results regarding the effect of glycemic index and glycemic load on fasting glucose levels and A1C, with one systematic review finding no significant impact on A1C (204) while others demonstrated A1C reductions of 0.15% (202) to 0.5% (190,205).