Introduction: Danielle Belardo MD
What if I told you that something you do every day, probably three times a day (or more), affects every cell and every organ system in your body?
Would you give this activity more thought?
The 'activity' I am referring to is more than just an activity, it is what sustains us, builds and repairs cells, and fuels us. It's eating.
We know that nutrition is linked to many disease processes, and some of the frequently cited organs affected are your heart (my favorite) and gastrointestinal tract.
But what if I told you that eating more plants, and less animal products, could help every single cell, tissue and organ in your body, from your spine to your eyes?
As a cardiology fellow who is passionate about plant-based nutrition and preventative medicine, I have sought out multiple physicians through social media to share evidence based nutrition with.
Eat more plants
I have connected with physicians all over the globe, spanning from omnivores to fully raw vegans, and there is one thing we all 100 percent agree on: eating MORE plant-forward, more fruits, vegetables, and greens, is better for you, no matter what.
In celebration of it recently being Women in Medicine Month, I asked 12 inspiring female physician friends of mine, some omnivore and some plant-based, spanning 12 different medical and surgical specialties, to share why eating plant-based foods helps prevent or reverse a disease process for both men and women, in their particular field.
Danielle Belardo, MD
Did you know that your heart beats about 100,000 times in one day? And about 35 million times in a year? During an average lifetime, the human heart will beat more than 2.5 billion times! I know I am a cardiologist so I may be biased but, I happen to think the heart is the most important organ (sorry Michelle McMacken, I know the pancreas is kind of cool too!).
The number one cause of death worldwide, for both men and women, is heart disease. In the US 2,200 people die of cardiovascular disease each day, and about every 40 seconds an American has a heart attack.
However, a significant amount of cardiovascular disease is preventable with lifestyle modification. There is a well-established body of literature that has shown that the more closely individuals follow a healthful plant-based diet, the lower their risk of coronary heart disease (1)*.
Additional studies have shown that healthful plant-based diets are associated with lower risk of all-cause mortality, and we have studies providing evidence of regression of coronary artery disease (demonstrated in coronary angiogram and stress imaging) when patients strictly adhere to a low-fat whole food plant based diet (2,3).
An inverse relationship between increased consumption of plant-based foods and incidence of heart failure has been demonstrated by several population-based cohort studies (6).
But just how does plant-based nutrition help to prevent and reverse cardiovascular disease? This is multifactorial. A low-fat whole food plant based diet decreases the incidence of many cardiovascular disease risk factors such as diabetes and hypertension.
Additionally, by eliminating animal products, dairy, and processed foods, you lower your intake of saturated fat. Plant-based diets lower blood cholesterol (total and LDL) by at least 35 percent shown in many studies. In addition to just lowering your cholesterol and risk factors for cardiovascular disease, plant based nutrition helps to decrease systemic inflammation as well.
The more we learn about the mechanisms of developing heart disease, the more we learn that inflammatory mechanisms are highly at play. There is substantial evidence that plant foods modulate and reduce immunological and inflammatory activities, and carotenoids and flavonoids modulate inflammatory as well as immunological processes.
Diets predominant in plant foods have been associated with decreased serum concentrations of the inflammatory biomarkers such as IL-6, CRP, soluble intercellular adhesion molecule-1, TNF (5).
Caldwell Esselstyn's study published in 2014 showed us that patients who adhered to a low fat, whole food, plant-based diet, had almost no major cardiac events over the study period (0.6 percent), 93 percent endorsed improvement in their chest pain, and coronary artery disease reversal was documented in 22 percent of patients. When compared to the patients who continued to eat animal products, 62 percent of which had suffered major cardiac events (3).
A great study published by Song, et al, showed us that replacing even three percent of your total calories with plant protein instead of animal protein was associated with substantial health benefits.
In this prospective cohort study of US health care professionals, over 130,000 participants with over 3.5 million person years of follow up showed that high animal protein intake was positively associated with cardiovascular mortality and high plant protein intake was inversely associated with all-cause and cardiovascular mortality (8).
The CARDIA study continued to prove the power of plants in a longitudinal cohort study designed to evaluate the progression of cardiovascular risk factors and CVD. The study found that fruit and vegetable intake during young adulthood was associated with a decreased prevalence of Coronary Artery Calcium later in life. (Coronary artery calcium (CAC), a direct marker of coronary atherosclerosis, is a strong predictor of future CHD events and a powerful CVD risk stratification tool (9).
These are just a few examples of peer-reviewed research studies which demonstrate how plant-based nutrition can prevent and reverse cardiovascular disease. Prevention through lifestyle modification and plant based nutrition is an incredible way to live a longer and healthier life.
*References are at the bottom of the page.
Type 2 Diabetes
Michelle McMacken, MD
Nearly one in 10 people in the United States have type 2 diabetes, and another 34 percent have pre-diabetes (1), a condition that confers a high risk of type 2 diabetes.
What causes these common health conditions?
At the basis of type 2 diabetes and prediabetes is a phenomenon called insulin resistance. This means that our cells don't respond to insulin properly - typically because certain types of fats build up in our muscle and liver cells. When this happens, our muscle cells can't take up as much glucose - a type of sugar that our cells rely on for energy - from our bloodstream. Also, our liver cells tend to overproduce glucose. Over time, this can lead to type 2 diabetes.
Why do some people develop insulin resistance? Many factors are at play, including genetics and race/ethnicity, but lifestyle behaviors are paramount.
Excess weight gain, a sedentary lifestyle, and a diet high in processed meats (eg., bacon, ham, and cold cuts), red meats, and/or sugar-sweetened beverages can all drive up the risk (2).
No matter our family history, we can greatly reduce our chances of developing type 2 diabetes - and even treat and potentially reverse it if we already have it - through our lifestyle choices. In addition to physical activity and a healthy body weight, eating patterns rich in whole grains, beans, fruits, and vegetables have demonstrated dramatic benefits in terms of preventing and treating type 2 diabetes (3,4).
In fact, studies show up to a 62 percent lower risk of type 2 diabetes for people eating healthy plant-centric diets, compared to people eating diets high in animal foods or highly processed plant foods – even with adjustments for differences in body weight and other risk factors (5). And in randomized trials among people with type 2 diabetes, a plant-based diet has been shown to be more effective in lowering blood sugar than a conventional diabetes diet (6).
How does a plant-based diet do this? It's rich in fiber, antioxidants, and micronutrients, all of which reduce insulin resistance (3). It also promotes a healthy body weight (7), less inflammation, and a healthier gut bacterial pattern, which also helps. At the same time, a plant-based diet is low or absent in diabetes-promoting factors such as saturated fats (8), animal protein (9), animal-based iron, advanced glycation endproducts, and nitrite preservatives (10).
The bottom line: when we build our diets on a framework of whole or less-processed plant foods, including vegetables, fruits, legumes, and whole grains, we stack the odds against developing not only type 2 diabetes, but a host of other chronic health conditions. Eating plant-based is a (delicious) recipe for vitality and longevity!
Irritable Bowel Syndrome: Nerves or Bacteria Related?
Angie Sadeghi, MD
IBS is the most common gastrointestinal disorder in the U.S., affecting an estimated 30 million people. Irritable bowel syndrome (IBS) is characterized by recurring symptoms of abdominal pain, diarrhea, constipation, and bloating. Treating IBS is important because the symptoms lead to a poor quality of life and reduced work productivity.
Many patients try to avoid social interactions because they are embarrassed by their symptoms.
Previously we thought IBS is due to stress, but psychological therapy has been ineffective in IBS.
A number of experiments have shown that people with IBS have a greater gastrointestinal reaction to stress than people without IBS, but studies thus far have failed to prove IBS is caused by stress.
A large study of US military members on active duty were used to identify incident IBS cases.The study found that a major risk factor for IBS was a history of infectious gastroenteritis (IGE).
Whether deployed or not, US service members often encounter repeated exposure to high levels of stress, but a history of infectious gastroenteritis was important and a major risk factor.
Recent studies show that IBS has to do with alterations in the intestinal microbiome, therefore therapies have been focused on targeting the intestinal microbiome for the treatment of IBS.
Treatment of IBS patients with antibiotics has shown to ameliorate symptoms of IBS and normalize the results of a test called the 'lactulose hydrogen breath test', which tests for the hydrogen-producing gut microbiome, which could lead to gas, bloating and diarrhea.
A study published in the New England Journal of Medicine in 2011 showed that among patients with IBS without constipation (with diarrhea), treatment with Rifaximin (an antibiotic) for two weeks provided significant relief of IBS symptoms, bloating, abdominal pain, and loose/watery stools.
Currently, the focus is to modulate the gut microbiome composition, to expand bacterial species considered as beneficial, and reduce those considered harmful, to attenuate IBS symptoms. The gut microbiota is a complex living ecosystem consisting of bacteria, virus, and yeast that occupy the GI tract. These living microorganisms encode for over three million genes, the so-called 'microbiome'.
The gut microbiome composition varies among individuals, changes during life, and depends on environmental factors, mainly lifestyle, diet, and drugs. The intestinal microbiota is dominated by two main phyla: Firmicutes, Bacteroidetes. In the healthy status, the gut microbiota interacts with the human host in a mutualistic relationship, where the host intestine provides the bacteria with an environment to grow, and the gut microbiome modulates several physiological functions such as nutrient processing and digestion, immune cell development and immune response, resistance to pathogens, and much more.
Changes in bacterial number and composition, the so-called dysbiosis, may induce a dysregulation of this deep relationship and cause a spectrum of diseases including inflammatory conditions. It is now recognized that a significant portion of the metabolites circulating in mammalian blood derives from the intestinal microbial community.
Moreover, it releases factors that target the nervous system to generate neurotransmitters such as dopamine, noradrenaline, acetylcholine and gamma-aminobutyric acid (GABA). Perhaps this is an area which needs to be studied in more detail which could hold the key to preventing Parkinson’s disease, and depression, and anxiety disorder.
Have you ever thought to yourself 'where does all this gas and bloating come from after I eat?'
Gas and bloating are the result of intestinal microbial metabolism, and subsequent fermentation, which produces carbon dioxide (CO 2 ), hydrogen (H 2 ), methane (CH 4 ), and hydrogen sulfide (H 2 S). H 2 S has been recently recognized as a gaseous neuromodulator/neurotransmitter capable of modulating intestinal inflammation such as inflammatory bowel disease.
In recent years, using culture-based techniques it has been demonstrated that the diversity of microbial population is reduced, the proportion of specific bacterial groups is altered in IBS patients when compared with healthy subjects. For example, there is a decreased number
of Lactobacilli and Bifido bacteria, and the mucosal bacteria have also been found to be more abundant in IBS patients than in healthy controls.
So, what does this mean for therapy? How do we increase the health promoting gut microbiome and decrease the number of inflammatory gut microbiome? What about taking probiotics in pill form? In order to be beneficial, probiotic bacteria must be able to survive along the gastrointestinal tract, to resist to gastric acid, bile, and pancreatic juice.
Several clinical trials have failed to provide robust data to prove taking probiotics are helpful. Fortunately, there is data which has shown pre-biotics, which are high fiber foods, such as fruits, vegetables, grains,
and of course legumes, promote the health-promoting gut microbiome.
Unfortunately, at the other side of the spectrum, meat, dairy, and eggs do the exact opposite, and feed the inflammatory gut microbiome.
In conclusion, if suffering from IBS, the focus should be to heal the gut by improving the gut microbiome composition. By eating a healthy diet plentiful in prebiotics (fiber), the gut microbiome composition improves and leads to the increase of health-promoting microbiome.
Fiber is found in vegetables, fruits, grains, and legumes. Moreover, avoiding meat, dairy, eggs, refined sugars, and processed foods can minimize the disease-promoting gut microbiome. This approach can slowly change the gut microbiome composition, and help you balance out the gut
In certain situations, individuals may need a 'kick start' using an antibiotic called Rifaxamine (in patients with diarrhea predominant IBS), but most of the effort should be placed on improving diet, because even with pharmacotherapy (Rifaxamine), IBS will recur without a change in diet.
Pamela Mehta, MD
In the last few years, there has been a growing body of evidence supporting a whole foods plant-based diet (WFPB) for general health benefits, prevention, and treatment of certain diseases, and weight reduction. A WFPB diet is easy to understand, inexpensive, practical, sustainable and requires limited materials.
Osteoarthritis (OA) - sometimes called degenerative joint disease or degenerative arthritis - is the most common form of arthritis, affecting 27 million people in the United States. It is the third leading cause of years lived with a disability and 20 percent of adults in the United States report having doctor-diagnosed osteoarthritis (1).
What is osteoarthritis? In healthy joints, cartilage provides a smooth, gliding surface for joint motion and acts as a cushion between the bones. In OA, the cartilage breaks down, causing pain, swelling and difficulty moving the joint.
The swelling or inflammation in the moving joint is perhaps the most painful and debilitating aspect of the disease. If a WFPB diet were proven effective to ameliorate the symptoms of osteoarthritis, this would be helpful to many people suffering with the disease.
Although, dietary treatment of rheumatoid arthritis is controversial several studies have shown favorable benefit in rheumatoid arthritis symptoms with dietary restrictions of meat and dairy products (2-5). Two studies have specifically investigated dietary modification and fibromyalgia- both showed beneficial effects (6-7).
After a thorough literature review, only one study - a six-week, prospective randomized trial - assessed the efficacy of a WFPB diet, compared with ordinary diet, on the reduction of osteoarthritis symptoms. Participants were randomized to a WFPB (intervention) or continuing current diet (control).
Outcomes were assessed by mixed models analysis of participant self-assessed weekly SF-36v2 domain t scores, weekly Patient Global Impression of Change (PGIC) scales, and mean weekly Visual Analog Scale (VAS) pain assessment. Mixed models analysis also evaluated pre-post change from baseline level for standard clinical measures: weight, BMI, body temperature, pulse, and blood pressure.
The intervention group reported significantly greater improvement than the control group in SF-36v2 energy/vitality, physical functioning, role physical, and the physical component summary scale. The differences between the intervention and control PGIC scales were statistically significant over time and the intervention group improvement in VAS weekly mean was also significantly greater than that of the control group from week two onward (8).
Overall, the study results suggest that a whole-foods, plant-based diet significantly improves functional status among osteoarthritis patients. Since we do not have evidence-based treatment to restore cartilage in osteoarthritic patients, it is of utmost importance to increase the methods we have in managing pain and inflammation. Hopefully, a WFPB diet will play a larger role in the treatment of osteoarthritic symptoms in the future.
Could going plant-based help my pelvic pain?
Sonia Bahlani, MD
Pelvic Pain Specialist
A question, believe it or not, I get asked a ton. Truth be told, the jury is still out. There are many causes of pelvic pain, so understanding the benefits of a plant-based diet in treatment of pelvic pain syndromes involves an understanding of the processes occurring.
There have been multiple studies citing the association between inflammation and various causes of pelvic pain, including endometriosis, interstitial cystitis, and pelvic floor dysfunction. Understanding this relationship is paramount in delving into the role of plant-based nutrition as an adjunct to current treatment strategies for prevention and treatment of pain syndromes.
What we know is that various studies have demonstrated an increase in inflammatory markers associated with causes of pelvic pain. And while understanding the true utility of elevated inflammatory markers remains unclear, it does beg the question: Can certain foods effect pelvic pain.
A recent study, published in AJOG, looked at the relationship between red meat consumption and endometriosis risk confirmed by laparoscopy (for those who don’t know this is considered gold standard for diagnosis). It did suggest that red meat consumption may be an important modifiable risk factor for endometriosis.
Plant-based nutrition for the win. Other studies, have looked at plant-based nutrition in terms of gut microbiome and symptom severity in patients suffering from pelvic pain. And while there's some data to suggest that increased consumption of meat and dairy can increase inflammation thereby exacerbating severity symptom scores in patients with pelvic pain.
Another argument (as if you really needed one) to support a plant heavy diet. Ultimately, it's important to remember that what we put into our bodies is ultimately what we get out of them. And as the old adage goes, 'you are what you eat'.
Diet and Fertility
Natalie Crawford, MD
Reproductive Endocrinology and Infertility
Fertility is notably difficult to evaluate as studies report heterogeneous outcomes and surrogate markers of fertility, such as time to pregnancy or successful outcome (pregnancy or live birth) after fertility treatments.
However, current evidence suggests that diet is a modifiable factor of female fertility. It appears that diets favoring whole grains, fruits, vegetables and polyunsaturated fatty acids are preferred for fertility.
Carbohydrates and fatty acids are important components of the human diet. It appears that both quantity and quality of carbohydrate intake impacts insulin sensitivity and glucose metabolism. Whole grains have antioxidant and anti-inflammatory properties which can result in beneficial impacts on glucose metabolism and have been associated with improved live birth rates (1-2).
Evidence suggests that diets higher in omega 3 polyunsaturated fatty acids and lower in trans fats are associated with both shorter time to pregnancy, improved ovulation, and improved outcomes with fertility treatments (3-8).
It appears that plant based eating improves reproductive outcomes. Ovulation is essential for reproduction, and increased vegetable protein intake improves ovulatory patterns (9). Similarly, embryo development in in vitro fertilization cycles decreased with increase in red meat consumption (10).
Studies evaluating fish consumption result in inconsistent results. Fish can be an excellent source of omega-3 polyunsaturated fatty acids although fish consumption also poses risk for environmental exposure, especially methyl mercury (11-13).
Evaluations of dairy intake have resulted in inconsistent impacts on reproductive outcomes. Total dairy intake has not been associated with decreased fertility; however two large cohort studies have revealed negative associations between dairy intake and fecundability (14-15).
There is concern that soy based protein intake may impair normal endocrine estrogen dependent pathways. (16-19). However, no correlation has been seen between soy intake and fecundity in prospective studies (20-21). Further, in patients undergoing fertility treatments, improvements in reproductive outcomes were seen in women with higher soy intake (22-25).
In summary, consumption of animal products provides an easy pathways for environmental contaminants to enter the human body. As female reproduction is a hormone dependent and sensitive process, it is hypothesized that increased consumption of animal based proteins (meat, dairy, eggs) may increase exposure to endocrine disrupting chemicals, steroid hormones, and growth hormones.
It appears that greater adherence to healthy diet patterns, including emphasis on whole grains, fruits, vegetables, and olive oil, may result in improved health and also improvement in fecundity.
Much has been discussed thus far on plant-based diets (PBDs) in relationship to different diseases and illnesses, but what about the disease of obesity? Can a plant-based diet help to treat this highly prevalent medical condition? Does switching to a mostly plant diet help you lose weight?
Several observational and intervention studies have been completed, and in general, a plant-based diet is associated with a lower body mass index (BMI). So, people who eat less meat tend to have healthier body weights. In fact, the Adventist Health Study noted that the amount of animal foods in the diet increased with BMI, such that vegans had the lowest BMI, followed by vegetarian, pesco-vegetarian, semi-vegetarian, and omnivorous diets (1).
The Swedish Mammography Cohort found that omnivores, or those that eat all food groups, had the highest prevalence of overweight and obesity compared to individuals following dietary patterns with less meat (1).
Knowing that a plant-based diet is associated with healthier body weight, interventional studies were done to compare outcomes in plant-eaters and meat-eaters. What has been consistently found is that a plant-based diet can help you lose weight. Barnard, et al., reviewed 15 clinical trials that used PBDs for at least four weeks without energy intake or Calorie restrictions. The researchers found that PBDs were associated with a mean weight loss between 3.4kg and 4.6kg.
Another analysis of 12 studies by Huang, et al. indicated significant weight loss among individuals assigned to PBDs. Amongst those studied, participants randomized to some type of vegetarian diet lost an average of −2.02 kg more than the participants assigned a non-vegetarian diet. Those on a vegan diet condition lost more weight than participants in a vegetarian diet condition (mean of −2.5 kg vs. −1.5 kg, respectively).
Other examples including the New DIETs study, HER Health Study, and the VA BEACH Diet Study all reported significant weight loss among individuals prescribed a PBD (1).
But is a plant-based diet healthy? Am I going to get all the nutrients I need? The Academy of Nutrition and Dietetics Position Paper states that vegan and vegetarian diets 'are healthful, nutritionally adequate, and may provide health benefits in the prevention and treatment of certain diseases' (1).
A well-planned vegetarian or vegan diet can supply all the nutrients required for good health (2). The long-term health of vegetarians appears to be generally good, and even better than that of omnivores for some diseases and medical conditions. Studies tell us there is a lower prevalence of obesity among western vegetarians, and lower weight gain in vegetarians and vegans during adulthood (2).
To summarize, PBDs are an excellent option for people who not only want to be healthy, but who may also want to lose weight. An added bonus includes improving dietary quality consistent with chronic disease prevention and treatment (1).
Children and Heart Disease Prevention
Renee Rodriguez Paro, MD
As a pediatric cardiologist, I see the results of our typical American diet firsthand - specifically children with abnormal cholesterol levels. It is widely known that childhood obesity is a worsening problem. Children who are overweight (BMI between the 85-95th percentile) or obese (BMI >95th percentile) have higher levels of lipid abnormalities (1). It is estimated that 20 percent of children aged 6-19 years have one or more abnormal lipid level: elevated total cholesterol >200; elevated LDL >130; elevated non-HDL cholesterol >145; or low HDL <35 (2). As the rate of pediatric obesity rises we wholeheartedly expect the prevalence of dyslipidemia to do the same.
Lipid levels in childhood are moderately predictive of adult levels (3). This is worrisome, as we know dyslipidemia is a leading cause of adverse cardiac events in adulthood. In pediatrics, the cornerstone of management is lifestyle modification – most notably in the area of nutrition. As a physician who regularly sees children with weight, cholesterol and blood sugar abnormalities, a few common trends became very clear – kids don't eat enough vegetables, kids consume too much sugar and kids need real food.
The benefits of a diet rich in fiber cannot be overstated. Fiber in conjunction with sterols/stanols found in non-starchy vegetables is a powerful combination for lowering cholesterol. A diet focused on consuming more plants along with little-to-no intake of trans/saturated fats has been shown to reduce BMI, blood pressure, waist circumference, insulin levels, and cholesterol (4).
Plant sterols also have the added benefit of reducing the amount of small density LDL (sdLDL) particles that are known to be more harmful in vascular disease (5). Many of my own patients have greatly improved their cholesterol profiles simply by eating more plants. How many vegetables should our kids eat? More. Many, many more.
When it comes to sugar, the culprit is fairly clear. Processed snacks run rampant in our children's lives and avoiding them takes real work. These foods carry tons of unnecessary added sugar. High blood sugar increases triglyceride levels along with the percentage of sdLDL particles. Long story short, they do nothing good for our kids’ bodies. How much of our kids' food should be processed? Less. Much, much less.
The evidence is clear - our kids need plants, and our kids need real food. The health of their hearts, for the rest of their lives, depends on it.
Peripheral Arterial Disease
Sondema Tarr, DPM
One of the scopes of practice that podiatrists have is the management of lower extremity wounds and infection; from private offices to the operating room. Over 2 million Americans are living with limb loss. Top causes for non-traumatic limb loss are Peripheral Arterial Disease (PAD) and Diabetes.
The five-year mortality rate of non-traumatic amputation is 50 percent; meaning that for every two people that undergo amputation of a toe, foot, or leg due to complications from vascular disease and or diabetes, one will be dead within five years. This mortality rate is three times higher than seen in breast cancer patients and five times higher than seen in prostate cancer patients. Non- traumatic limb amputation is a serious issue within the U.S.
Unfortunately, not enough light is shed on this subject. PAD is caused by fatty plaque deposits inside arteries that supply blood to other parts of the body, outside of the heart or brain. Any tissues that are downstream from this plaque will not receive enough oxygen or nutrients. Someone with PAD that affects the leg will have symptoms such as pain/cramping brought about by walking, or decreased hair growth. As PAD progresses, the pain becomes constant and can worsen while sleeping. Severe PAD can lead to chronic non- healing ulcers, subsequent infection, and gangrene. Treatment for gangrene is surgery, (removal of dead tissue/bone and or amputation) along IV antibiotics. Gangrene is irreversible.
A study performed in Brazil in 2008 compared 1,267 participants. Data about their diet and laboratory markers were collected. Ankle Brachial Index (a measurement of blood flow to the leg) was used to identify subjects with PAD. 14.6 percent of these participants had PAD. Among
these subjects, there was significant association between PAD with high total fat intake, specifically saturated fat (found in all animal products, as well as many processed foods, coconut oil, and palm oil) and low intake of fiber from fruit and whole grains.
Another study published by the European Society of Clinical Nutrition and Metabolism this year showed that increased fruit and vegetable intake had a protective effect on ABI in women who had PAD and high blood pressure.
Increased fruit, vegetable, and whole grain intake are hallmarks of a healthy diet. There many more studies that show how plant foods may reduce the risk or alleviate early symptoms of PAD in the lower extremity. Adding more whole plant foods into the diet is something each person should strive for.
Spine and Joint Pain
Annie Purcell, DO
As a physician specializing in Spine and Sports medicine, there are many aspects of my practice where prescribing a plant-based diet has significant benefits for my patients. I see people all day long with spine and joint pain who improve secondary to the weight loss (1) and the anti-inflammatory benefits that this diet can provide. (2) (3) The anti-inflammatory properties of plants such as turmeric (4) and watermelon (5) (6) have helped them rely less on taking Ibuprofen, saving them from side effects such as ulcers, intestinal bleeding and kidney damage. (7)
However, the most dramatic benefit I have seen from prescribing a plant-based diet is not well known in the medical community and is definitely not something that I was taught in my training as a Physiatrist.
The pain caused by diabetic peripheral neuropathy had been one of the most difficult conditions to treat in the early years of my practice. Patients came to me after taking multiple prescription medications, none of which helped enough for the pain, and many of which had significant side effect profiles with risks outweighing the slight benefits.
Many of my patients were tormented by this pain, unable to sleep due to the relentless burning sensations caused by their damaged nerves. After reading a study which showed regression of diabetic neuropathy with a vegan diet, (8) I went to work convincing my patients to try the plant-based diet. I advised them that in the study, twenty-one diabetics suffering from painful neuropathy were placed on a whole-food, plant-based diet and seventeen out of twenty-one felt complete relief of their pain within days!
The first time I was able to convince one of my patients to try, it resulted in my first ever painful diabetic neuropathy treatment slam dunk! He had total resolution of the burning pain which had haunted him for years and the numbness also improved. We were both shocked and overjoyed.
Although I was happy for him and my future patients who would benefit from this discovery, it was difficult for me to accept how many patients I had failed in the past by lacking insight into the power that a plant-based diet could provide. The pain relief my patients have experienced is significant enough that they would never consider stopping the whole-food,plant-based diet.
Allison Young, MD
When I ask patients permission to discuss their diets, I'm typically met with a reluctance. Is this really relevant to my mental health? Should we take up precious session time on food? My answer to both of these questions is a resounding yes.
There is a growing body of evidence linking food choices with brain function and susceptibility to mental illness. Evidence of the benefits of plant-based foods is building for multiple mental disorders, with the greatest amount of evidence for depression. Multiple observational studies have shown that those who consume larger quantities of fruits and vegetables experience fewer depressive symptoms and enhanced emotional well-being when compared to those who eat a standard Western diet, which is traditionally low in plant-based foods (1,2,3).
Recently, a study took these data a step farther by studying whether a modified Mediterranean diet high in fruits, vegetables, legumes, and whole grains could actually treat depression in those experiencing a major depressive episode. This randomized-controlled trial found significant improvement in the symptoms of major depressive episode in those in the healthful diet group when compared to the control group, who received support without nutritional intervention (4). Together, these studies suggest that modification of diet, especially the consumption of large quantities of fruit and vegetables, may have a role in the prevention and treatment of depression.
The mechanism through which plant-based foods improve depressive symptoms is still unknown, with potential mechanisms including direct effect on neural growth factors and/or mediation through gut microbiota, inflammatory factors, and/or oxidative stress pathways.
The importance of dietary intervention in those with mental illness extends beyond psychological symptoms. Those with severe mental illness die 10-20 years earlier than the general population.
This is largely due to increased rates of physical illnesses, mainly heart disease and diabetes (5). The higher rates of these preventable illnesses is thought to be due to poorer lifestyle choices (people with mental illness are less likely to exercise and more likely to eat processed foods) combined with the use of psychiatric medications, many of which cause increased appetite and weight gain.
Thus, while more research is needed to determine exactly how improvement in diet leads to improvement in mood, mental health professionals should not wait for this research. Prescribing fruits and vegetables to this population has no risk attached to it, but has the significant potential benefit of enhancing one's quality and quantity of life.
Jennifer Tsai, OD
As an eye doctor practicing in New York, the most common questions I receive is how to maintain healthy eyes and great vision. Based on a Bausch + Lomb survey, four of five participants consider vision as their most important sense, however, the majority of the participants do not know the proper nutritional diet for their eyes.
It is important to educate the importance of healthy intake of whole foods like plants, fresh fruits, vegetables, and grains that provide great nutrients for eye health and reduce the likelihood of eye diseases.
Green leafy vegetables like kale and spinach provide nutrients rich in lutein and zeaxanthin. They are beta carotenoids antioxidants to protect the eye tissue from light-induced damage, caused by conditions like macular degeneration. They also help with oxidative damage to the lens that sits inside your eyes to slow down cataract formation.
An important study called ARED2 performed by National Eye Institute, showed that a daily intake of beta-carotene, vitamin C, vitamin E, zinc and copper reduced the risk of macular degeneration by 25 percent. Vegetables rich in orange pigment help support vision and boost eye health.
The most well known of them all is carrots, however sweet potatoes, pumpkin, and orange peppers are also great for your eyes and contain carotenoids. Beta carotene is a precursor of Vitamin A which prevents dry eyes, macular degeneration, and cataracts.
Whole grains like oat and quinoa help reduce blood sugar spikes, which can cause diabetic retinopathy if not controlled. Diabetes can cause retinal vessels to leak fluid and blood, causing vision loss. A study by Diabetes Journal found that diabetic retinopathy is the leading cause of blindness for those aged 20-74. Whole grains contain zinc, which helps Vitamin A to create melanin to protect the retinal tissue and reduce night vision loss. Nuts like chia and flax seeds are rich in omega-3 fatty acids and great for reducing dry eyes and meibomian gland dysfunction.
Fruits like blueberries provide key ingredients like vitamin A and antioxidants to prevent free radical oxidation. In particular, it contains anthocyanins which have shown to help eyes recover after exposure to a bright light.
This is important for dark adaptation like during night driving. Citrus fruits like oranges and lemons are packed with Vitamin C. Vitamin C promotes healthy retinal capillaries, which are tiny structures that transport oxygen retinal tissue in our eyes.
Children and Asthma
Jackie Busse, MD
Asthma is a chronic inflammatory condition of the airways that affects nearly 10 percent of all US children - about 6 million kids (1). It is the #1 chronic disease of childhood in the US - but that isn’t the case everywhere. Asthma prevalence worldwide ranges from less than one percent to more than 30 percent!
This wide disparity is not due to differences in air quality or smoke exposure but differences in diet. Where there is higher consumption of fresh fruits, vegetables, whole grains, and other plant foods, there are lower rates of asthma (2).
Numerous studies have confirmed: the more plants kids eat, the less asthma they have! Kids who eat the most fruits and veggies (5-7+ servings/day) have less than half the risk of asthma compared to kids who eat the least (0-3 servings/day).
Eating more fruits and veggies each day results in significant improvements in lung function (FEV1). This is true even with modest changes such as going from zero to one serving per day (3,4).
So, how does eating a more plant-based diet protect against asthma?
Healthy Body Weight
Plant foods are naturally high in fiber and low in calories so kids who eat more plants tend to have lower body weight and BMI. An obese child has a 50 percent increased risk of asthma (5).
More 'Good' Fats, Less 'Bad' Fats
Plants foods have more omega 3 fatty acids (anti-inflammatory) compared to omega 6 (inflammatory). That higher ratio of omega 3 to 6 fatty acids is associated with a significantly lower risk of asthma in kids (6).
Lower Sodium Intake
Unprocessed plant foods are naturally low in sodium. There is a strong correlation between high salt intake and high rates of asthma (7).
Increased Intake of Antioxidants
Antioxidants are only found in plant foods and they are critical to our body's ability to fight disease. By increasing our intake of fruits and vegetables (again, even by just 1-2 servings a day), we can increase our levels of antioxidants, improve our lungs' defense systems and decrease asthma symptoms (8).
Healthier Gut Bacteria
The protective effect of plant foods may also be due to their beneficial impact on the intestinal microbiome. A healthy gut flora is essential for a strong immune system and children with asthma lack key healthy bacteria found on fruits and veggies (9).
Danielle Belardo MD
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Michelle McMacken, MD
Angie Sadeghi, MD
Pamela Mehta, MD
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Natalie Crawford, MD
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1. Turner-McGrievy G, Mandes T, Crimarco A. A plant-based diet for overweight and obesity prevention and treatment. Journal of Geriatric Cardiology : JGC. 2017;14(5):369-374. doi:10.11909/j.issn.1671-5411.2017.05.002.
Renee Rodriguez Paro, MD
2. Trends in serum lipids among youts aged 16-19 years (1988-2010), Kit BK, Carroll MD, Lacher DA, Sorlie PD, DeJesus JM, Ogden C. JAMA. 2012 Aug; 308 (6) 591-600 [please note: this is apdf available online]
4. Plant Based, No-Added-Fat or American Heat Association Diets: Impact on Cardiovascular Risk in Obese Children with Hypercholesterolemia and Their Patients. Michael Macknin MD, Tammie Kong MS, RD, Adam Weier MS, RD, Sarah Worly MS, Anne S. Tang MS, Naim Alkhouri MD, Mladen Golubic MD, PhD. The Journal of Pediatrics. 2015 Apr 166 (4) 953-959
5. Plant sterols-enriched diet decreases small, dense LDL-cholesterol levels in children with hypercholesterolemia: a prospective study. Anastasia Garoufi, Styliani Vorre, Alexandra Sodatou, Charalampos Tsentidis, Lydia Kossiva, Antonios Drakatos, Antonios Marmarinos, Dimitrios Gourgiotis. Italian Journal of Pediatrics. 2014 Apr 40:42
Sondema Tarr, DPM
1. Clougherty, C. (2018). Soft Tissue Coverage and Foot Amputations. [PowerPoint Slides]
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3. Mattioli, A. V., Francesca, C., Mario, M., & Alberto, F. (2018). Fruit and vegetables in hypertensive women with asymptomatic peripheral arterial disease. Clinical Nutrition ESPEN, 27, 110-112. doi:1
Annie Purcell, DO
1. Mirmiran P, Bahadoran Z, Golzarand M, Shiva N, Azizi F. Association between dietary phytochemical index and 3-year changes in weight, waist circumference and body adiposity index in adults: Tehran Lipid and Glucose study. Nutr Metab (Lond). 2012;9(1):108.
2. Khadem Haghighian M, Alipoor B, Malek Mahdavi A, Eftekhar Sadat B, Asghari Jafarabadi M, Moghaddam A. Effects of sesame seed supplementation on inflammatory factors and oxidative stress biomarkers in patients with knee osteoarthritis. Acta Med Iran. 2015;53(4):207-13.
3. Bliddal H, Rosetzsky A, Schlichting P, Weidner MS, Anderson LA, Ibfelt HH, Christensen K, Jensen ON, Barslev J. A randomized, placebo-controlled, cross-over study of ginger extracts and ibuprofen in osteoarthritis. Osteoarthritis Cartilage. 2000 Jan;8(1):9-12.
Allison Young, MD
1. McMartin, S.E., Jacka, F.N., Colman, I. The association between fruit and vegetable consumption and mental health disorders: evidence from five waves of a national survey of Canadians. Preventative Medicine. 2013;56(3-4):225-230.
3. Agarwal, U., Mishra, S., Levin, S., Gonzales, J., Barnard N,D. A multicenter randomized controlled trial of a nutrition intervention program in a multiethnic adult population in the corporate setting reduces depression and anxiety and improves quality of life: the GEICO study. American Journal of Health Promotion. 2015;29(4):245-254.
4. Jacka, F.N., O’Neil, A., Opie, R., Itsiopoulos, C., Cotton, S., Mohebbi, M., Castle, D., Dash, S., Mihalopoulos, C., Chatterton, M Brazionis, L., Dean, O.M., Hodge, A.M., Berk, M. A randomised controlled trial of dietary improvement for adults with major depression (the ‘SMILES’ trial). BMC Medicine. 2017;15(1):23.
5. Liu, N.H., et al. Excess mortality in persons with severe mental disorders: a multilevel intervention framework and priorities for clinical practice, policy and research agendas. World Psychiatry. 2017;16(1):30-40.
Jennifer Tsai, OD
2. Diabetic Retinopathy, Donald S. Fong, MD, MPH, Lloyd Aiello, MD, PHD, Thomas W. Gardner, MD, George L. King, MD, George Blankenship, MD, Jerry D. Cavallerano, OD, PHD, Fredrick L. Ferris III, MD, Ronald Klein, MD, MPH and for the American Diabetes Association.
Jackie Busse, MD
2. Asher MI, Stewart AW, Mallol J, Montefort S, Lai CK, Aït-Khaled N, Odhiambo J; ISAAC Phase One Study Group. Which population level environmental factors are associated with asthma, rhinoconjunctivitis and eczema? Review of the ecological analyses of ISAAC Phase One. Respir Res. 2010(11):8.