Definition/Introduction

Lifestyle medicine is a branch of evidence-based healthcare emphasizing disease prevention over curative medicine. Contemporary medicine follows the same basic approach to the clinical encounter: data-gathering, conducting any needed tests, providing the patient with a treatment plan, and possibly a referral or hospital admission. This approach can be described as essentially end-stage care. The modern character of healthcare has neglected prevention. Patients often receive little or no practical education on disease prevention. Studies employing direct observation of primary care practices have reported that preventive care has been underemphasized.[1] 

The reasons for this may be varied, with some suggesting that too much time is required to provide the information needed by the typical patient visit.[2] This reactive, curative approach has important implications for healthcare financing.

The cost of healthcare in the United States has become prohibitive. At the time of this publication, it is estimated that the cost to provide care to the average adult is over $13,000 annually in the US.[3] The Centers for Disease Control (CDC) reports that six in ten Americans have a chronic disease, and two in four have two or more chronic diseases. These conditions account for approximately 75% of all healthcare costs.[4][5] 

Chronic diseases include heart disease, Alzheimer disease, type II diabetes, cancer, stroke, and other similar disease processes. The United States is the outlier of all countries in healthcare expenditures, spending far more per capita as a function of GDP (gross domestic product).[6] Thus, if healthcare providers intervene to integrate prevention into their workflow, then we may see a significant decrease in the number of chronic diseases for individuals, the associated suffering, and healthcare costs for both individuals and the government.

Issues of Concern

A major, compelling solution to the challenge of healthcare, both on the individual and collective levels, is to effect preventive change through lifestyle modification. This concept is not new: Hippocrates taught about the importance of prevention over 2000 years ago.[7] The medieval physician and philosopher Maimonides asserted that the most important cause of poor health is the food we choose to eat.[8] 

It has been estimated that only one-fifth of the modifiable determinants of healthcare come from the care medical practitioners provide (figure 1).[9] Despite this, modern healthcare has heavily emphasized curative treatment over prevention. Preventing chronic disease may be the key to the healthcare financing crisis in the US and other nations and the overall improved health of the population taken as a whole.

In 2009, researchers analyzed lifestyle and body weight using pre-existing data from the large European Prospective Investigation Into Cancer and Nutrition–Potsdam study.[10][11][12] They identified four healthy lifestyle practices and body weight characteristics among German adults that predicted a composite healthy outcome. They noted a significant decrease in major chronic diseases for those with all four characteristics. The four predictive factors included having a body mass index (BMI) of less than 30 kg/m2, performing 3.5 h/wk of moderate physical activity, consuming a predominantly plant-based diet (whole-grain with low meat consumption), and never smoking.

Patients with these four characteristics had almost a four-fifths reduction in chronic disease (78%, 95% CI 27 to 83%) after adjusting for sex, age, occupational and educational status. A subsequent study using the National Health and Nutrition Examination Survey found that only 2.7% of Americans have a lifestyle that approximates the four factors mentioned in the previous study.[13] Although it is possible to avoid chronic disease through commonly attainable lifestyle changes, very few Americans take advantage of this opportunity.

Clinical Significance

Most people do not seek care until a disease process has already manifested, and this trend worsened with the COVID-19 pandemic.[14][15] Patients with diabetes or congestive heart failure (CHF) typically present for medical attention months after a symptom has been bothering them. Many of them have not seen a medical professional for months to years. Thus, how much time does a medical provider have to intervene before the disease process takes root? They may be presenting very late in the course of their illness. Obesity is also an important risk factor for many chronic diseases. Obesity rates have been increasing in the US, as evident in the CDC geographic data comparison of 1985 versus 1995 (Figures 1, 2). Based on the evidence presented in the studies mentioned above and others, prevention is key. 

Evidence shows that the sequelae of adverse health behavioral choices can be partially corrected. In a non-controlled study from a single physician practice, Dr. Caldwell Esselstyn reported on patients who were rejected as candidates for bypass surgery and put on a lipid-lowering drug and a vegetarian diet with little vegetable oils. These patients demonstrated a subsequent widening of their coronary arteries.[16] 

In 1998, a seminal study by Dr. Dean Ornish and collaborators was a landmark for initiating change. The article, entitled "Intensive Lifestyle Changes for Reversal of Coronary Heart Disease," compared 28 patients who had coronary artery disease and tried lifestyle intervention, compared to a cohort of patients who did not receive any intervention.[17] The study was conducted over five years. Lifestyle interventions included maintaining a primarily vegetarian diet emphasizing whole foods, exercise, smoking cessation, and counseling. A clinically and statistically significant reduction in the stenosis in coronary arteries was experienced in the intervention cohort versus those in the control group, who continued to use lipid-lowering pharmacotherapy. This seminal trial demonstrated that coronary artery disease could be reversed.  

The American College of Lifestyle Medicine promulgates evidence that reinforces the importance of a diet containing fruits, vegetables, whole grains, unprocessed foods, and limited amounts of meat. These diet changes may have a substantial impact on obesity. A recent meta-analysis by Schlesinger et al. examined the risk of weight gain in relation to certain food groups.[18]

They saw a decreased relative risk of fat in muscle the more a vegetarian diet was invoked. This and other studies suggest that increasing vegetables in one's diet are associated with a decreased relative risk of obesity, and increasing red meat intake is associated with a greater risk. There are multiple reasons for this, one of them being that the saturated fat content in red meat is often neglected. Saturated fats exist not only in red meats but also in other foods such as butter and cheese. Therefore, through education in lifestyle choices, one can choose to avoid saturated fats, achieving less future chronic disease and the associated pain and suffering.

Diabetes mellitus is another chronic disease process that is very common and significantly affects a patient's health and lifestyle. In 2002, Knowler et al. demonstrated that lifestyle interventions focusing on weight loss outperformed metformin in patients with type II diabetes mellitus.[19] 

They compared three interventional groups: lifestyle changes, metformin, and placebo. The lifestyle group was given a low-calorie & low-fat diet (almost vegetarian) and 150 minutes of physical activity per week. From this study, it is noteworthy that lifestyle changes outperformed metformin for preventing diabetes. Diabetes is also highly associated with obesity, and healthcare providers need improved strategies for weight loss. Obesity is increasing at alarming rates in the US. In 1985, no state had greater than a 14% prevalence of obesity. However, on the map 2010, greater than 30% of American adults are obese (figure 1, figure 2). In 2005, Dansinger et al. compared four diets regarding weight loss and heart disease risk reduction: Atkins, Ornish, Weight Watchers(R), and Zone diets.[20][21] 

All diets were noted to be successful at weight loss, directly related to regimen compliance. Ketogenic diets have become quite popular recently and often lead to successful weight loss. However, there is evidence that ketogenic diets (that encourage meat consumption) appear to be correlated with increased mortality.[21] This may be a result of the increase in saturated fats.[21]

In another study, the Portfolio diet (a diet of cholesterol-lowering foods) was administered to patients with high cholesterol levels.[22] The interventional group was compared to a control cohort taking lovastatin (a known cholesterol-lowering drug). In both groups, serum lipids and C-reactive protein were tracked. Cholesterol-lowering foods included whole grains, low-fat cereals, and increased use of vegetables. This study showed that it is possible to duplicate the benefits of statin with a targeted diet. The Adventist study was a large population-based longitudinal study of 96,000 patients, which compared vegetarians to meat-eaters.[23]  

Over a decade of observation, vegetarians had lower all-cause mortality and lower ischemic heart disease, cardiovascular disease, and cancer incidence. Diabetes was also less prevalent among vegetarians. The article concluded that vegetarians were healthier. A subgroup analysis compared three groups: vegans, lacto-ovo vegetarians, and pescatarians. It was reported that the "pescatarian" group was associated with the lowest all-cause mortality rate and decreased incidence of type II diabetes mellitus. Studies like this one suggest that diet is generally the most crucial lifestyle modification.

Another important, well-established aspect of preventive health is exercise. The effect of decreasing mortality through exercise is greatest with the first 150-200 minutes of moderate exercise per week, with additional exertional duration providing incrementally less benefit.[24] According to the US Preventive Services Taskforce (USPSTF), almost 70% of mortality reduction benefit is achieved with 150 minutes of moderate exercise per week.[25][26] That roughly equals 30 minutes of moderate activity per day for five days a week. The talk test is a useful estimation of moderate exercise.[27] If one can talk but not sing, that can be considered moderate exercise to comply with the USPSTF recommendations for exercise. If one is exercising and cannot talk, that is considered vigorous.

Sleep is another area emphasized in lifestyle preventive health. Analyzing all-cause mortality in a sleep duration study published by the American Heart Journal, it is noted that mortality decreases as one approaches a daily sleep duration of seven hours and increases with sleep duration beyond eight hours.[28]

Sometimes societal constructs use lack of sleep as a feature of strength and "hard work," but it must be noted that this is not conducive to overall life performance. Lack of sleep is shown to decrease productivity and have consequences in the form of chronic diseases, including total cardiovascular disease and stroke.[28] Additionally, multiple studies suggest insufficient sleep is associated with Alzheimer disease.[29][30][31][32] Thus, current evidence suggests that achieving seven to eight hours of sleep is an appropriate lifestyle modification recommendation. 

Smoking, if habitual, is another significant risk factor for disease and mortality.[33] Many well-documented dangers of addictive substances increase cancer risk and heart disease risk. Smoking is a more substantial risk factor for chronic disease than diet and exercise.[34] Thus, smoking must be eliminated from all lifestyles to avoid severe, predictable chronic diseases.  

Stress and social isolation are other risk factors affecting chronic disease. Stress has been described as a risk factor for disease and overall mortality.[35][36] As such, stress management can aid in identifying positive and negative stress responses, identify coping mechanisms, and teach stress-reduction techniques for improved well-being. Social isolation has also been associated with increased mortality, so social connectedness as a preventive strategy is also an area of recent investigation, especially among the aging population.[37][38][39] Social connections can also aid in emotional resiliency and overall health.

The goal of lifestyle modification as a preventative medicine is to make daily changes that are relatively easy to perform, adjust to, and uphold in terms of future daily habits. By educating our patients about these preventative lifestyle modifications, we can help them understand the consequences and implications of poor choices. In this regard, one can minimize future pain and suffering caused by a chronic disease process that has poor prospects for a cure but appears to be preventative and/or reversible – such as strokes, heart attacks, kidney failure, and the use of chronic dialysis.

In summary, even though prevention is not a revolutionary topic in medicine, it is neglected in most modern medical practices. Evidence-based lifestyle changes must be increasingly emphasized in the practitioner-patient encounter. Nutrition and exercise are the most important lifestyle modifications for nonsmoking patients. Patients should be encouraged to choose a diet predominantly of fiber-filled, nutrient-dense foods, thus promoting health. Additionally, regular and consistent physical activity is essential to an optimal health equation. Lack of quality sleep can detrimentally impact both of these modifications mentioned above. Substance abuse must be considered an essential modification as well.

Nursing, Allied Health, and Interprofessional Team Interventions

The commercial media heavily promotes unhealthy lifestyle choices. Another popular example of a dangerous element of the western diet is bacon. Bacon is an example of processed meat that is now classified as a Group 1 carcinogen by the International Agency for Research on Cancer (IARC) list, the same as many more well-known carcinogens.[40][41] Yet, despite being known to cause cancer, bacon can be found at nearly every commercial fast food establishment across the U.S. and every grocery store.

There has also been some interest in making healthy food the default option in hospitals and medical centers. It is crucially important for these institutions to provide food prepared for patients based on a healthy lifestyle approach.[42] 

All interprofessional healthcare team members should be included in the patient education and support process. Therefore, all healthcare team members must participate in preventive education and support of the patients in their care.