The Role of Dietary Lifestyle Modification in Chronic Disease Prevention and Management

Function

Maintaining a balanced diet is essential for achieving optimal nutrition and overall well-being. Healthy eating habits can significantly influence health outcomes by improving physiological and psychological parameters. Proper nutrition provides various benefits, including better mood regulation, enhanced functioning of vital organs, and a reduced risk of chronic conditions such as cancer, diabetes, and cardiovascular disease (CVD).

The impact of daily nutrient intake on health outcomes is often overlooked by individuals and their healthcare providers. Prioritizing a nutrient-rich diet—one that is low in saturated and trans fats, added sugars, and excessive sodium—is essential for promoting long-term health and well-being. This approach supports better physical health and aids in disease prevention, ultimately improving quality of life. Evidence-based dietary modifications are crucial in improving health outcomes, with an emphasis on individualized counseling and active patient engagement to support informed lifestyle changes. Understanding the relationship between nutrition and health empowers individuals to make intentional choices that enhance overall wellness and lower the risk of diet-related chronic diseases.

Issues of Concern

Recent data on hypertension, obesity, and chronic kidney disease (CKD) in the United States indicate concerning trends. Between August 2021 and August 2023, approximately 47.7% of adults were diagnosed with hypertension, with a higher prevalence among men (50.8%) than women (44.6%).[1] In 2023, approximately 40.3% of adults were classified as obese, with the highest prevalence rates (46.4%) observed among individuals aged 40 to 59.[2] CKD currently affects approximately 14% of the adult population in the United States, increasing to 34% among individuals aged 65 and older, thereby rendering it a significant contributor to morbidity and mortality.[3] Diabetes remains the leading risk factor for kidney failure, and is responsible for nearly half of all new cases. Effective management of these conditions necessitates comprehensive lifestyle interventions, including dietary modifications and increased physical activity.

Sodium and potassium are essential in regulating blood pressure and kidney function, with significant implications for cardiovascular and renal health. Excessive sodium intake, which is common in Western diets, is strongly associated with elevated blood pressure. Reducing dietary sodium to recommended levels (<2 g/d) can lower both systolic and diastolic blood pressure, with particularly notable effects observed in individuals with hypertension and across genetically diverse populations.[4][5] However, the impact of sodium reduction on lipid profiles remains debated, as studies show mixed results regarding its influence on cholesterol and triglyceride levels.[6] Additionally, high sodium intake is associated with an increased risk of CKD and worsening proteinuria. In contrast, sodium restriction has demonstrated benefits in patients with CKD and diabetic nephropathy by reducing urinary albumin excretion and slowing disease progression.[7][8]

Higher potassium intake is inversely associated with blood pressure and CVD risk. Increased dietary potassium intake has been shown to reduce systolic and diastolic blood pressure by 3.49/1.96 mm Hg in adults, with the greatest benefits observed in individuals with low baseline potassium levels or high sodium intake.[9] Incorporating potassium-rich foods, such as bananas, oranges, leafy greens, potatoes, and mushrooms, into the diet while limiting sodium intake can significantly improve cardiovascular and renal outcomes. These dietary modifications are essential components for managing hypertension and CKD and reducing the risk of stroke. Further research is warranted to elucidate the mechanisms underlying these effects and optimize dietary recommendations for diverse populations.[10]

Beyond hypertension, CVD, and CKD, a range of other chronic conditions—including prediabetes, type 2 diabetes, dyslipidemia, obesity, and metabolic dysfunction–associated steatotic liver disease (MASLD)—can benefit substantially from dietary lifestyle changes. For individuals with prediabetes and diabetes, carbohydrate-controlled, low-glycemic diets aid in blood glucose regulation and help reduce the risk of long-term complications. Plant-based and Mediterranean-style diets have demonstrated effectiveness in improving lipid profiles, lowering cardiovascular risk, and supporting both weight loss and weight maintenance. Diets low in saturated fats and high in fiber promote healthier cholesterol levels, while reducing added sugars and refined carbohydrates can improve liver function and decrease hepatic fat accumulation in patients with MASLD.

Clinical Significance

Evidence-based dietary patterns are essential for the prevention and management of chronic diseases. Below is an overview of key models supported by scientific research, their components, and recommended clinical applications.

Mediterranean Diet as a Model for Chronic Disease Prevention

The Mediterranean diet, which is characterized by a high intake of plant-based foods, olive oil, nuts, and fish, has been shown to reduce the risk of CVD by 10% to 67% for fatal events and 21% to 70% for nonfatal events, particularly in secondary prevention populations.[11] The anti-inflammatory properties of this diet, attributed to antioxidants and polyphenols, help mitigate noncommunicable diseases by modulating endothelial dysfunction and inflammatory pathways. Despite declining adherence globally, the Mediterranean diet remains the gold standard for managing CVD and metabolic syndrome, supported by a robust evidence base that demonstrates improvements in lipid profiles, glycemic control, inflammation, and overall cardiovascular outcomes.[12][13]

Dietary Approaches to Stop Hypertension and Cardiovascular Health

The Dietary Approaches to Stop Hypertension (DASH) diet, which focuses on fruits, vegetables, whole grains, and low-fat dairy products, has been shown to reduce systolic and diastolic blood pressure by 3.2 and 2.5 mm Hg, respectively, in both hypertensive and normotensive adults.[12] More significant benefits are observed in individuals with higher baseline sodium intake (>2400 mg/d) and in younger populations aged 50 or younger. A 2023 review underscores the DASH diet’s efficacy in managing heart failure, dyslipidemia, and uric acid levels, further reinforcing its role in reducing hypertension-related morbidity.[14]

Plant-Based Diets

Plant-based diets have been shown to lower all-cause mortality and reduce the incidence of CVD by improving metabolic profiles and enhancing gut microbiome diversity. A 2025 systematic review of 32 longitudinal studies found an association between plant-based dietary patterns and a reduced prevalence of obesity, type 2 diabetes, and systemic inflammation. However, the heterogeneity in diet definitions and study populations limits the generalizability and interpretability of these findings.[15][16]

Low-Fat Diets

The primary objective of low-fat diets is to reduce the proportion of calories derived from fat. Some strategies are very low in fat, with fat accounting for less than 10% of total daily calories, while others are more moderate, with fat comprising less than 30% of daily caloric intake. Multiple randomized controlled trials have shown that reducing fat intake to below 30% of total calories leads to greater weight loss, particularly in individuals with higher body mass index (BMI) and those with lower baseline fat intake. The reduction in body weight was also accompanied by a slight decrease in percent body fat, low-density lipoprotein (LDL) cholesterol, and total cholesterol, with minimal impact on high-density lipoprotein (HDL) cholesterol, triglycerides, or systolic and diastolic blood pressures.[17] 

A randomized controlled trial found that a low-fat, plant-based diet intervention led to weight loss by decreasing overall energy intake and improving postprandial metabolism, which was associated with increased insulin sensitivity.[18] Although low-fat diets may contribute to reductions in body weight and cholesterol levels, they do not appear to improve overall survival from coronary heart disease.[19] Furthermore, dietary fat intake should be carefully monitored, as an unhealthy low-fat diet is associated with a modest increase in mortality. In contrast, a healthy low-fat diet is linked to a lower mortality rate.[20] Dietary fats from nontropical plant oils, fatty fish, whole grains, vegetables, whole fruits, and nuts are associated with more favorable health outcomes compared to fats from animal sources and tropical plant oils. These plant-based fats are particularly beneficial for cardiovascular health and reducing the risk of chronic diseases.

Low-Carbohydrate Diets

Low-carbohydrate diets restrict intake of sugars (mono- and disaccharides), oligosaccharides, and polysaccharides such as starches and fibers. The Dietary Guidelines for Americans recommend that 45% to 60% of daily energy intake come from carbohydrates; however, in response to the rising prevalence of obesity and a growing emphasis on weight loss, many individuals are reducing their carbohydrate consumption. In a randomized trial, a lower carbohydrate intake was associated with increased energy expenditure during weight loss maintenance. Participants on a low-carbohydrate diet also had significantly lower levels of ghrelin—the hormone that stimulates hunger—compared to those on a high-carbohydrate diet. However, leptin levels, which regulate satiety, were also reduced.[21] Compared to a low-fat diet, a low-carbohydrate diet generally results in a comparable rate of weight loss in adults with obesity, with both approaches leading to significantly greater weight reduction than an unrestricted diet.[22]

Ketogenic Diets

The ketogenic (or "keto") diet is one of the most widely adopted low-carbohydrate dietary approaches. This diet emphasizes high fat, low carbohydrate, and moderate protein intake, typically adhering to a 3:1 fat-to-protein ratio or a 4:1 fat-to-carbohydrate ratio. Multiple studies have demonstrated its anti-epileptic effects, particularly in children with drug-resistant epilepsy. Pediatric patients with seizures following a ketogenic diet were 5.6 times more likely to experience a 50% reduction in seizures compared to the control group after 3 months on the diet. However, the ketogenic diet may be less effective for treating epilepsy in adults.[23][24] 

Although the quantity of carbohydrates is often emphasized, focusing on the quality of carbohydrates is essential by prioritizing those with a low glycemic index. Compared to low-glycemic index carbohydrates, high-glycemic index carbohydrates are broken down more rapidly, leading to a quicker increase in serum glucose during digestion. The ketogenic diet has a mixed effect on lipid levels, with its impact varying depending on an individual's baseline metabolic profile, the types of fats consumed, and the duration of the diet. The ketogenic diet can improve glycemic control, lower hemoglobin A1c (HbA1c), and support weight loss in patients with type 2 diabetes. However, it may increase LDL cholesterol levels and can be challenging to maintain long-term. While the American Diabetes Association acknowledges the ketogenic diet as a valid option for some patients, it should be individualized and closely monitored, particularly regarding medication adjustments and nutrient intake.

Low-Calorie and Very Low-Calorie Diets

A low-calorie diet (LCD) typically provides 800 to 1200 kilocalories daily and focuses on gradual weight loss through moderate calorie restriction. A very low-calorie diet (VLCD) offers fewer than 800 kcal per day, often using meal replacements, and is medically supervised for rapid weight loss in specific populations, such as those with severe obesity or type 2 diabetes.[25] VLCDs result in significantly greater short-term weight loss compared to LCDs. In a study involving obese women with polycystic ovary syndrome, an 8-week VLCD led to a 10.9% reduction in initial body weight, markedly outperforming a moderate energy deficit diet, which achieved a 3.9% reduction.[26] A systematic review of VLCDs in patients with type 2 diabetes reported a mean weight loss of 13.2 kg and an HbA1c reduction of 1.4%, along with improvements in lipid profiles and blood pressure.[27] 

VLCDs effectively reduce fat mass while preserving lean muscle mass, particularly when paired with protein supplementation. For example, a ketogenic VLCD incorporating synthetic amino acids decreased visceral fat and LDL cholesterol without inducing sarcopenia.[28] VLCDs improve glycemic control in patients with type 2 diabetes, with some studies demonstrating reduced insulin requirements and sustained reductions in HbA1c following the dietary intervention.[27] VLCDs are also effective in lowering systolic and diastolic blood pressure by 8% to 13% and reducing triglyceride levels by 15% to 50% in individuals with obesity.[29] 

Although VLCDs may cause transient adverse effects, such as fatigue and constipation, they are generally considered safe when implemented under appropriate medical supervision.[30] VLCDs are typically recommended for short-term use, generally lasting 12 to 16 weeks under close medical supervision. They are most suitable for individuals with severe obesity and are often used to achieve rapid weight loss before surgery or as a starting point for long-term weight management strategies.

Other Dietary Recommendations

Consuming whole grains has been shown to reduce diastolic blood pressure by 5.8 mm Hg in overweight adults compared to refined grains, independent of weight loss. A high fiber intake (28–30 g/d) lowers LDL cholesterol and CVD risk, improves digestive health, enhances satiety, provides higher nutrient density, and reduces the risk of colorectal cancer.[31][32] Several dietary guidelines also emphasize limiting the intake of sugars and ultra-processed foods. Each additional daily serving of ultra-processed food is associated with a 2% increased risk of developing diabetes, with the strongest links observed for sugar-sweetened beverages, processed meats, and sugary snacks. According to the American Heart Association, reducing added sugar intake to fewer than 25 grams daily in children can help lower the risk of adiposity and dyslipidemia.[33][34]

Other Issues

Intermittent Fasting

In recent years, intermittent fasting has gained significant attention, with numerous systematic reviews and meta-analyses examining its effects on weight management, metabolic health, and disease-specific outcomes. This approach involves alternating between periods of eating and fasting.[35] 

The main types of intermittent fasting include:

• Time-restricted eating: This approach involves fasting for 12 to 20 hours each day, followed by an eating window of 4 to 12 hours. Common variations are mentioned below.
  • 16:8 Fasting: This involves fasting for 16 hours with an 8-hour eating window, which has been associated with reduced daily caloric intake and weight loss.
  • 18:6 Fasting: This involves fasting for 18 hours, which may provide enhanced metabolic health benefits.
• Alternate-day fasting: This method alternates between fasting days, where you consume less than 25% of your daily calorie needs, and non-fasting days. Common variations are listed below.
  • Complete alternate-day fasting: No calorie intake on fasting days.
  • Modified alternate-day fasting: Allows 500 to 600 calories on fasting days.
• 5:2 Diet: This involves eating normally 5 days per week and restricting calorie intake to 500 to 600 calories on 2 nonconsecutive days.
• Eat-stop-eat: This involves fasting for 24 hours once or twice per week, which many individuals find challenging.
• One meal a day: This entails consuming a single meal within a 1-hour window, resulting in a 23-hour fasting period. Concerns include long-term sustainability and meeting nutritional requirements.
• Warrior diet: This involves consuming small amounts of raw fruits and vegetables during the day and a large meal at night, typically within a 4-hour eating window.
• Extended fasting: This refers to fasting for more than 24 hours; this approach may pose health risks and generally requires medical supervision.

Each intermittent fasting method offers distinct potential benefits and limitations. Evidence suggests that intermittent fasting significantly reduces body weight and fat mass compared to nonintervention diets, as reported by Yao K et al.[36] However, although intermittent fasting is effective for weight loss, its advantages over caloric restriction are minimal. A 2024 meta-analysis of adults with prediabetes or type 2 diabetes found that intermittent fasting resulted in an additional weight loss of just 1.14 kg compared to caloric restriction, with no significant differences in glycemic or lipid markers.[37] Intermittent fasting also lowers LDL cholesterol, triglycerides, and total cholesterol compared to nonintervention diets, but the benefits over caloric restriction are minimal.[38] Intermittent fasting also reduces systolic blood pressure and fasting insulin, although these effects are generally weaker than those of caloric restriction.

In individuals with type 2 diabetes, intermittent fasting has been shown to lower HbA1c by 0.81% and reduce fasting glucose levels by 0.36 mmol/L.[39][40] Among the various approaches, alternate-day fasting provides the most substantial benefits for improving adiposity, lipid homeostasis, and blood pressure in obese individuals. Cheng et al confirmed that time-restricted eating combined with exercise reduces fat and body fat percentage without compromising muscle mass.[41] Although intermittent fasting supports weight loss and glycemic control in type 2 diabetes, its effects on insulin resistance and lipid profiles are largely comparable to those of traditional caloric restriction.[42]

Enhancing Healthcare Team Outcomes

Physicians play a pivotal role in dietary counseling by translating nutrition science into personalized care strategies. However, limited nutrition education during medical training often undermines their confidence and competence in delivering practical, evidence-based dietary guidance.[43] Continuing medical education in nutrition is essential for effectively applying evidence-based dietary recommendations in patient care. Establishing clear benchmarks and competencies for nutritional knowledge within medical education could significantly enhance physicians' ability to engage patients in meaningful discussions about dietary changes. Additionally, interdisciplinary collaboration with registered dietitians can enrich the depth and accuracy of dietary counseling.[44]

Practical tools and standardized resources can help bridge the gap between clinical consultations and patient adherence to dietary recommendations. Currently, only 36% of hospital discharge instructions worldwide include nutritional information, highlighting systemic barriers to implementing dietary interventions, as noted by Aggarwal et al.[45] Expanding these resources to include condition-specific dietary guidance could significantly improve patient outcomes. For example, incorporating recommendations for adequate protein intake and low-glycemic food choices into discharge instructions for patients with gestational diabetes mellitus has been shown to enhance adherence and health outcomes. Providing clinicians with practical, evidence-based tools can help establish a continuum of care that supports long-term adherence to dietary guidance.[46]

With their deep understanding of disease mechanisms and continuous, thorough patient interactions, specialist physicians are uniquely positioned to personalize dietary interventions. This individualized approach is especially beneficial for patients with chronic conditions, such as diabetes and CVDs, where tailored dietary guidance can lead to significant improvements. For example, managing carbohydrate intake to around 130 grams per day has been shown to improve glycemic control and reduce medication dependence in patients with type 2 diabetes. However, such dietary modifications require intensive patient education and practical advice.

Compliance largely depends on helping patients understand the underlying physiology, which should be explained in clear, patient-friendly terms.[47] In the context of CVD, clinical nutrition strategies focus on reducing intake of energy-dense, nutrient-poor foods, particularly those high in saturated fats, trans fats, cholesterol, and sodium. Adhering to these dietary modifications has been shown to significantly reduce the risk of adverse cardiovascular events.[48] By delivering these targeted interventions, physicians can align patient care plans with evidence-based nutritional strategies that support optimal health outcomes.

Physicians often face systemic barriers, such as limited time during consultations, that constrain their ability to provide detailed dietary counseling. Addressing these challenges requires the integration of innovative tools and the collaboration of interdisciplinary healthcare providers. Evidence-based dietary counseling, led by well-informed physicians, has demonstrated substantial effectiveness in managing hypertension and type 2 diabetes. For instance, incorporating potassium-rich foods through the DASH diet has been shown to effectively regulate blood pressure and reduce associated risks.[49] 

When nurses, physician assistants, registered dietitians, pharmacists, and community health workers collaborate with physicians, patients are more likely to receive comprehensive nutritional counseling. Integrating all interprofessional healthcare team members into clinical workflows helps alleviate time constraints on clinicians while ensuring patients receive well-rounded dietary guidance. Additionally, obesity management through clinical nutrition interventions, which focus on sustainable weight loss and improving metabolic health, demonstrates how physicians can enhance patient outcomes through such collaborative efforts.[50]

Motivational interviewing has emerged as an effective strategy for promoting dietary behavior change. This patient-centered, collaborative approach emphasizes enhancing intrinsic motivation rather than using directive persuasion. Evidence indicates that motivational interviewing improves outcomes such as reductions in BMI and cholesterol levels and enhances overall adherence to dietary recommendations.[51]

Motivational interviewing, which focuses on assessing patient readiness and incorporating motivational strategies, fosters a supportive environment that enhances the sustainability of healthier dietary practices. This approach is especially effective when combined with the managed care model, which integrates patient education and interdisciplinary care to support ongoing dietary and lifestyle changes in managing chronic conditions, such as diabetes. Please see StatPearls' companion resource, "Motivational Interviewing," for more information. Culturally sensitive strategies must be prioritized to meet the diverse needs of patients from different backgrounds. Minority populations, such as Black and Hispanic communities in the United States, often exhibit higher prevalence rates of chronic diseases such as diabetes and obesity due to systemic inequities.[52] Tailoring dietary recommendations to align with cultural preferences and transcultural adaptations can enhance both acceptability and efficacy. For example, culturally tailored meal planning can help reduce resistance to unfamiliar foods while ensuring nutritional adequacy. Additionally, providing economically feasible recommendations that focus on affordable, nutrient-dense foods, such as legumes and whole grains, can help address socioeconomic barriers to healthy eating.[53] Healthcare team members must adopt a holistic approach that considers both socioeconomic and cultural factors when developing dietary interventions.

Digital tools and technological innovations offer promising opportunities to enhance dietary adherence. Integrating these tools into clinical practice can improve patient outcomes by enabling more personalized nutritional monitoring. Furthermore, hybrid approaches, such as combining physician-led counseling with genetic testing, have shown behavioral changes, including reduced consumption of red meat and pastries, which align with evidence-based dietary guidelines.[54]

Leveraging advanced strategies allows physicians to overcome systemic barriers, such as time constraints, while promoting sustainable dietary changes that benefit patients. Nutritional recommendations that emphasize dietary fiber, healthy fat sources, and portion control—such as those used in medical nutrition therapy for diabetes—exemplify the value of combining evidence-based guidelines with innovative interventions to prevent and manage chronic diseases.[48]

Addressing psychological and physical barriers, such as sarcopenia and fatigue, is crucial for patients with chronic illnesses such as cirrhosis. These challenges hinder individuals' ability to adopt potentially problematic dietary and lifestyle changes, further complicating disease management. Research shows that exercise training, combined with personalized nutritional guidance, can improve key health outcomes, including muscle health, functional capacity, and overall quality of life in populations with chronic diseases.[55] This highlights the importance of integrating exercise prescriptions into routine dietary counseling to help patients overcome these barriers.

However, implementing these strategies remains challenging, particularly for patients with advanced symptoms or limited physical capabilities. Personalized care approaches that address both psychological and physical difficulties are essential for enhancing adherence and supporting long-term health improvements. Future studies could explore the role of virtual exercise programs and telehealth nutrition counseling in offering accessible and supportive interventions for individuals facing mobility constraints or resource limitations.

Building sustainable and healthy dietary habits requires strategies grounded in behavioral change theories and frameworks that promote long-term habit formation. While perceived health benefits often serve as initial motivators, maintaining adherence over time can be a significant challenge, potentially deterring individuals from continuing lifestyle modifications.[56] Techniques such as goal setting, self-monitoring, and reinforcement have been shown to positively impact dietary behavior by fostering accountability and providing a sense of accomplishment. For example, goal setting helps individuals outline specific, achievable objectives, while self-monitoring enables them to track their progress, which can enhance motivation and commitment.[57][58] Reinforcement strategies, including verbal affirmations and recognition of milestones by the healthcare team, further support patients in adopting healthier dietary and lifestyle changes. Please see StatPearls' companion resource, "Behavior Modification for Lifestyle Improvement," for more information.