Internists routinely ask patients about smoking and drinking, but should they also ask about eating habits?
If the basic mission of medicine is to protect patients' health, then the answer is an obvious yes, according to David L. Katz, MD, MPH, FACP, director of the Yale-Griffin Prevention Research Center in Derby, Conn. “The evidence-based argument for the relevance of diet is quite simply overwhelming,” he said. “There is no drug we prescribe that everybody should take, there is no procedure we can recommend that everybody should get, but the effects of diet on health are absolutely universal.”
Research suggests that behavioral risk factors, such as poor diet, account for up to half of premature deaths in the U.S., according to a 2015 report by the National Research Council and Institute of Medicine. In 2010, poor diet and lack of exercise accounted for 18% of total deaths, overtaking tobacco (15%) as the No. 1 risk factor for premature death, according to the report.
And in primary care, the consequences of poor nutrition chronically manifest as cardiovascular disease, diabetes, and hyperlipidemia. Realizing this burden, the U.S. Department of Health and Human Services set goals in its Healthy People 2010 and 2020 initiatives to increase the proportion of physician office visits that include nutrition counseling for patients with these conditions.
The proportion of such visits decreased from 42% in 1997 to 28% in 2007, according to data cited in the Healthy People 2010 report, which failed to meet its ambitious target of 75%. The Healthy People 2020 report pinned the 2007 proportion at just 20.8% of visits when including patients with physician-reported conditions not reflected by ICD-9 codes. The new report sets a more modest target of 22.9% for 2020. It also aims to increase the proportion of visits made by adults with obesity that include counseling on weight reduction, nutrition, or physical activity from 28.9% in 2007 to 31.8% by 2020.
However, barriers such as time restrictions, lack of training, and inadequate reimbursement discourage internists from incorporating nutrition into their encounters, experts said.
“The thing is, many physicians don't feel prepared. They don't feel they have enough information to tell their patients anything, so often, they either tell them nothing or they recommend a place to go … but many times, it's not completely useful,” said Louis Aronne, MD, FACP, a professor of metabolic research at Weill-Cornell Medical College and director of the Center for Weight Management and Metabolic Clinical Research in New York.
More than 20 years ago, Robert F. Kushner, MD, FACP, surveyed 1,030 primary care physicians to assess the barriers to nutrition counseling. The top obstacles were lack of time, patient nonadherence, inadequate teaching materials, lack of counseling training, lack of knowledge, inadequate reimbursement, and low physician confidence, according to results published in the November 1995 issue of Preventive Medicine. The same issues continue to stall change in this space, according to a follow-up paper published in the October 2010 issue of Nutrition in Clinical Practice.
Time is, of course, a limited resource in primary care environments. “Could everybody benefit from [nutrition counseling]? I bet they could. The problem is there is not enough time to speak to every single person,” said Dr. Aronne.
Rajeev Saini, MBBS, FACP, an internist at Northway Medical Associates in New York, said he tries to incorporate nutrition counseling into his practice but quickly listed these numerous challenges. “We are all so busy taking care of our patients who have so many needs that we really don't have the time,” he said. “And even if you have the time, you don't have the resources to educate them about nutrition. You want to have a nutritionist in your practice, but unfortunately these services are not covered by insurance.”
Even when insurance does cover referrals to nutrition counseling because of underlying medical conditions, the advice isn't always helpful for patients, Dr. Saini said. “When you send a patient to a nutritionist in the hospital, they are trained to educate them about diabetes, or they talk about a low-salt diet in high blood pressure, but no one gives them basic information about how to eat healthy,” he said.
In terms of training, threads of lifestyle medicine are only now beginning to be introduced into medical education, said Dr. Kushner, a professor of medicine at Northwestern University Feinberg School of Medicine in Chicago. “For all the internists in practice, chances are they had very little training in nutrition, so they're playing catch-up,” he said.
But even modern medical school curricula may not be prioritizing nutrition. Since 2000, researchers at the University of North Carolina at Chapel Hill have conducted nutrition education surveys of U.S. medical schools in four-year intervals. In the most recent survey, 18% of schools reported that their required curriculum during the 2012-2013 academic year included a dedicated nutrition course, compared to 35% in 2000, 30% in 2004, and 25% in 2008, according to results published in 2015 by the Journal of Biomedical Education.
Experts offered ways for internists to save time, increase their knowledge, and work with other clinicians to help their patients improve their diets.
Since there are no standardized, universally used screening instruments for diet, internists may find utility in a previsit screener that asks patients about their eating habits, Dr. Kushner suggested. Prescreening information could include 24-hour recall of the food and drink patients consume or a “food frequency” log of particular food groups, he said. “That would be my recommendation, as far as how to expedite the clinical encounter and get the patient's information,” said Dr. Kushner.
Once that information is obtained, it's not necessarily the physician who needs to directly counsel the patient, Dr. Aronne noted. In a large practice, for example, a nurse, nurse practitioner, registered dietician, or other clinician could take on this job, he said.
If an internist chooses to refer patients to receive comprehensive nutrition counseling, he or she should first provide some overarching principles and long-term goals, Dr. Kushner said. “A doctor doesn't have to do it all himself or herself, but they do need to be part of the solution. They need to provide guidance and support,” he said.
Part of that guidance, for example, could be a recommendation for a patient to start tracking his or her food intake, Dr. Kushner suggested. “No matter what behavior you want to change, if you track it and monitor it, you're more likely to be successful,” he said. With the use of technology, a patient can easily create a personal, electronic dashboard of their food intake, body weight, and physical activity, “the three most important measurements a patient can have at their disposal to make decisions and have a sense of control over what they're doing with their body,” he said.
In addition to referring patients to a local nutritionist or a trained nurse in his office, Dr. Saini will briefly counsel patients, providing some literature on healthy eating and keeping advice simple. “I'll sit with them and ask, ‘How do you want to eat healthy?’ Then we pick one meal and talk about what they can do to improve that,” he said. As a bariatrician, Dr. Saini also sees patients who want to lose weight, counseling them every one to three months and making sure to document the topics covered in the EHR.
Although experts have for decades advocated for more nutrition education in medical school, training has become more competency-based in such relevant areas as communication and interprofessional teamwork skills, said Robert Baron, MD, MS, a primary care physician and associate dean for graduate and continuing medical education at the University of California, San Francisco. “There are … more opportunities to learn the skills that one needs to be effective in nutrition counseling than there were 30, 40 years ago,” he said. “It may not be as bad as we think.”
Widespread consensus about which foods best support longevity and vitality has actually remained relatively unchanged despite years of media-spun confusion, the experts said. A healthy eating pattern includes a variety of vegetables, fruits, grains (especially whole grains), fat-free or low-fat dairy, lean protein sources, and oils while limiting saturated fats, trans fats, added sugars, and sodium, according to the 2015-2020 Dietary Guidelines for Americans. The guidelines committee's evidence review methods, notably regarding saturated fat and red meat, were called into question in an investigation published in September 2015 by The BMJ. In December 2016, after formal reviews were conducted by two independent experts, the BMJ article withstood calls for retraction by more than 170 researchers but was subject to a few corrections and clarifications.
Meanwhile, popular styles of eating in U.S. dieting culture also seem to be at odds with each other (e.g., low-fat/vegetarian vs. high-fat Mediterranean diets). However, many of these diets consistently include an emphasis on whole plant foods and limitations on refined starches, added sugars, and processed foods, according to a March 2014 review coauthored by Dr. Katz and published in Annual Review of Public Health. “This notion that we can't agree about the fundamentals of good nutrition is belied by the peer-reviewed evidence,” Dr. Katz said.
New research continues to underscore the beneficial effect of a plant-based diet on health outcomes. A large prospective cohort study found that high animal protein intake was positively associated with cardiovascular mortality, whereas high plant protein intake was inversely associated with both all-cause and cardiovascular mortality, according to results published in October 2016 by JAMA Internal Medicine. Furthermore, substituting plant protein for animal protein (especially that from processed red meat) was linked with lower mortality, the study found.
A meta-analysis of 86 cross-sectional and 10 prospective cohort studies also found benefits of a plant-based diet. Compared to omnivores, vegetarians and vegans had significantly reduced levels of body mass index, total cholesterol, LDL cholesterol, and glucose levels, according to results published in February 2016 by Critical Reviews in Food Science and Nutrition. The review also found that compared to omnivores, vegetarians had a 25% reduced risk of incidence of and mortality from ischemic heart disease and an 8% reduced risk of cancer, although there was no significant protection against overall mortality or cardiovascular and cerebrovascular diseases.
Clinicians don't have to counsel all of their patients to become vegetarians, of course. In the name of simplicity, Dr. Baron advocates for a “generic” diet. “I think we can make our nutrition counseling more straightforward. Almost all experts agree that you need a diet which is mostly plant-based: lots of vegetables and fruits and some amount of whole grains, nuts, and legumes. Most patients would also include some amount of eggs and dairy products and a modest amount of fish, chicken, and meat,” he said. “You can tinker with the different amounts of those things, but at the end of the day, the evidence is pretty straightforward.”
Dr. Aronne noted that he takes a relaxed approach with patients to develop a sustainable way of eating. “One of the things we've learned about diet is that everybody does not benefit from the same diet,” he said. “The best diet is the diet that you like the best. We don't force people to do anything.”
Notably, “nutrient fixations” (e.g., low carbohydrate, low fat) tend to be little more than unhelpful distractions, Dr. Katz said. “If the food's right, the nutrients take care of themselves. The problem is: It's simple; it's just not easy. And the reason it's not easy is because everywhere you go is highly processed junk food. The world makes it hard.”
The right interval for follow-up on nutrition is a matter of opinion, Dr. Baron said. “I would use the Diabetes Prevention Program as the gold standard, since it's the strongest evidence base, and more insurance programs are now covering it,” he said. Program participants attended at least 16 sessions in the first 24 weeks before meeting monthly with case managers, either individually or in groups. But success ultimately depends on patient adherence, Dr. Baron said. “In every study that has looked at dietary change for weight loss or some other change, no matter how often the follow-up was arranged, adherence to the follow-up was a major predictor of success,” he said.
As for tailoring dietary advice to individual patients, Dr. Kushner pointed out a condition that is relevant to two out of every three patients: overweight and obesity. “Right away, that should alert the internist to be asking questions and doing some counseling on excess caloric intake and focusing on where those extra calories could be coming from,” he said.
The U.S. Preventive Services Task Force (USPSTF) recommends offering or referring adults who are overweight or obese and have additional risk factors for cardiovascular disease (e.g., hypertension, diabetes) to intensive behavioral counseling interventions to promote a healthful diet and physical activity, according to a B-grade recommendation published in 2014 by Annals of Internal Medicine.
Dr. Kushner suggested asking patients in this category whether they eat until they're beyond full, whether they dine out often, and whether their portion sizes are larger than needed. Another important intervention is avoiding highly processed foods and beverages with added sugar and refined carbohydrates, Dr. Baron said.
For those with hypertension, internists should be sure to emphasize the importance of reducing added salt, Dr. Kushner said. Nutrition counseling of this nature is often already embedded in internists' practice as part of chronic disease management. “Either they're already doing it but they don't recognize it, or they think they're doing it but they're not doing a very good job,” he said, offering the example of telling a patient with hypertension to stop adding salt without bothering to ascertain the actual sources of salt in the diet.
For adults ages 40 to 70 who are overweight or obese, the USPSTF recommends screening for abnormal blood glucose as part of cardiovascular risk assessment and offering or referring those with abnormal blood glucose to these behavioral counseling interventions, according to a B-grade recommendation published in 2015 by Annals of Internal Medicine.
For patients with diabetes, some dietary tips that tend to work well are to have a protein-rich breakfast and have vegetables or protein at the beginning of each meal, Dr. Aronne suggested. “That lowers how much your sugar goes up when you eat something,” he said.
Most recently, the USPSTF published last November a C-grade draft recommendation statement suggesting that primary care clinicians individualize the decision to offer or refer such interventions to adults without obesity who do not have hypertension, dyslipidemia, abnormal blood glucose, or diabetes. The task force cited a “positive but small benefit of behavioral counseling for the prevention of cardiovascular disease in this population,” although it found inadequate direct evidence of a reduction in mortality or cardiovascular disease rates. The USPSTF noted that such interventions pose minimal harms and that potential benefits include improvements in blood pressure, LDL cholesterol, body mass index, and waist circumference that persist for six to 12 months.
But even after receiving advice on good eating habits, patients return to a culture where food is readily available, convenient, processed, and highly palatable. “Teaching nutrition is one thing, but people need to be taught how to cook also, and how to use the right ingredients to cook healthy,” Dr. Saini said.
This food culture makes it even more crucial for internists to address the critical contribution of nutrition to health, Dr. Katz said. “The argument for doing it is absolutely compelling, the barriers to doing it are considerable, and the cultural conspiracy against the success of these efforts is unconscionable,” he said. “But I think internists have a role to play in addressing all of that.”