Abstract 

The consumption of plant-based foods has been associated with decreased mortality and an overall improvement in health. In light of such findings, this paper presents a holistic overview of plant-based diets, including best practices for defining and implementing them. Thereafter, the strength and consistency of the evidence for plant-based diets from randomized clinical trials and observational research are examined. These studies demonstrate the beneficial effects of plant-based diets for people who suffer from cardiovascular diseases and type 2 diabetes. This paper then explores the limitations of plant-based diets. Although such diets can exert a powerful impact on human well-being, plant-based foods may not be readily accessible to financially impoverished populations throughout the United States. Moreover, there are a number of additional challenges to consumption that must be addressed, including food neophobia and environmental sustainability. Overall, however, this paper recommends that increased prominence and accessibility should be placed on plant-based foods nationwide. 

Overview of Plant-Based Diets

Plant-based diets can be defined not merely as containing fruits and vegetables, but also seeds, oils, nuts,  beans, whole grains, and legumes. For the purposes of this research paper, “plant-based” includes vegan and vegetarian diets. “Vegan diets contain only plant foods, while lacto-ovo-vegetarian diets include dairy and/or egg products” (Kahleova et al.). In addition to being higher in fiber and phytonutrients, plant-based diets can provide the protein, lipids, carbohydrates, vitamins, and minerals required for optimal health. “However, some vegans may need to add a supplement (specifically vitamin B12) to ensure they receive all the nutrients required” (McManus). 

It is important to note that not all plant-based foods are the same. There is a large assortment of plant-based diets available, each with possibly varied health consequences that depend upon the quality of plants that are consumed. There are two distinct categories of plant-based foods. One is a “healthful plant-based index that positively weighs healthy plant foods (e.g. whole grains, fruits, vegetables, nuts, legumes)” (Satija and Hu). The other type of plant-based foods have been shown to have less beneficial effects on human health. These plant-based foods include, but are not limited to, less healthy options such as “refined grains, potatoes, and sugar-sweetened beverages” (Satija and Hu). An unhealthful plant-based diet can have various negative consequences on cardio-metabolic health. For these reasons, this research paper uses the term ‘plant-based diet’ and similar terminology to refer exclusively to healthful plant-based foods. 

There are multiple variations of positive plant-based diets that can be implemented. Plant-based diet advocates advise that whole grains such as oatmeal, quinoa, buckwheat, and barley are considered to be part of a complete breakfast. Breakfasts may also include moderate helpings of seeds and nuts, as well as fresh fruit (McManus). It is also recommended that people fill at least half of their plates with vegetables at lunch and dinner. Vegetables can be enjoyed with other plant-based toppings such as salsa, hummus, and guacamole. In addition, it is recommended that processed meats should be used primarily as a garnish rather than as a centerpiece of one’s diet (McManus). Doing so can help limit one’s consumption of them. Another recommendation is for people to wisely select the fats that they consume on a daily, consistent basis. “Fats in olive oil, olives, nuts and nut butters, seeds, and avocados are particularly healthy choices” (McManus). To add variety to plant-based diets, green leafy vegetables such as collards, spinach, kale, Swiss chard, and other greens can be consumed on a daily basis. Grilling, steaming, or stir-frying such vegetables can help preserve the amount of nutrients that they provide.

Cardiovascular Diseases and Plant-Based Diets 

Overview

Cardiovascular diseases (CVDs) are a group of disorders pertaining to the relationship between the human heart and its associated blood vessels. CVDs include coronary heart disease, cerebrovascular disease, peripheral arterial disease, rheumatic heart disease, congenital heart disease, deep vein thrombosis, and pulmonary embolism (World Health Organization). Heart attacks and strokes can indicate the presence of CVDs. They are typically sudden, severe events that may be traced to a blockage that stops the flow of blood to the heart or brain. “The most common reason for this is a build-up of fatty deposits on the inner walls of the blood vessels that supply the heart or brain. Strokes can be caused by bleeding from a blood vessel in the brain or from blood clots” (World Health Organization). CVDs frequently have no symptoms aside from heart attacks or strokes. 

Health Benefits and Plant-Based Diets

CVDs are leading causes of mortality. In fact, they have been estimated to account for one in four deaths worldwide (Lozano et al.). A recent investigation even found that high sodium diets, processed meat product consumption, and low intakes of fruits and vegetables were linked to 45.5% of cardio-metabolic fatalities nationwide (Micha et al.). There are multiple rigorous scientific studies, however, that have reported an important remedy to this issue. Specifically, plant-based diets rich in whole grains, fruits, vegetables, and nuts have been associated with a lower risk of CVDs and overall positive health (Satija and Hu). When combined with exercise and stress management, a low-fat, vegetarian diet can yield remarkable results for people. This plant-based regimen has lead to a “...cessation and reversal of atherosclerotic plaque in clinical trials. Vegetarian diets are associated with a reduced risk for cardiovascular disease in general, including a reduced risk for ischemic heart disease and cerebrovascular disease” (Kahleova et al.). 

Furthermore, people who eat vegetarian diets have fewer risk factors for heart disease. In fact, vegetarians had a 32% lower risk of coronary heart disease than non-vegetarians according to the European Prospective Investigation into Cancer and Nutrition study (Crowe et al.). A considerable preventive benefit of a vegetarian diet against CVDs was recently uncovered through a comprehensive review and meta-analysis of 86 cross-sectional and 10 cohort prospective studies. When compared to non-vegetarian eating habits, vegetarians were 25% less likely to develop CVDs (Kahleova et al.). This trend was found to be most significant among men versus women, younger participants, and those who had adhered to a vegetarian diet for a longer period of time.

Additional studies discovered that pro-vegetarian diets are commonly associated with a lower rate of cardiovascular mortality for at least over five years (Martinez-Gonzalez et al.). Furthermore, several randomized controlled trials have been conducted to investigate the influence of vegetarian diets on intermediate risk factors for CVDs. In a meta-analysis of randomized controlled trials, vegetarian diets were found to significantly lower blood concentrations of total, LDL, HDL, and non-HDL cholesterol when compared to multiple non-vegetarian control diets (Satija and Hu). 

Further studies have discovered that vegetarian diets can even lower additional risk-factors for CVDs. These risk factors include increases in blood pressure, body mass indices, and glycemia (Yokoyama et al.). One way in which these excellent benefits are achieved is through the impact of plant-based diets on biological pathways. Due to their low saturated fat and high fiber content, such diets are likely to have less calories. This, in turn, can aid in weight loss and long-term weight maintenance. Dietary fiber, in particular, may reduce calorie intake by inducing satiety cues such as increased stomach distention (Satija and Hu). This can ultimately be attributed to increased chewing of fibrous foods and intestinal gel formation as a result of water absorption by soluble fiber.

Polyphenols that derive from plant-based diets can also play key roles in promoting cardiovascular health. “Polyphenols, organic compounds found abundantly in plants, have become an emerging field of interest in nutrition in recent decades. A growing body of research indicates that polyphenol consumption may play a vital role in health through the regulation of metabolism, weight, chronic disease, and cell proliferation. Over 8,000 polyphenols have thus far been identified…” (Cory et al.). There are two main characteristics of polyphenols that can help limit the onset of CVDs. The first notable polyphenol property is its antioxidant capabilities. This is important because antioxidants play a role in “...scavenging and neutralizing free oxygen and nitrogen species and protecting against oxidative stress” (Satija and Hu). Nitric oxide modulation is another vital aspect of polyphenols. When combined with antioxidation, nitric oxide modulation “...enables polyphenol compounds to help maintain vascular homeostasis” (Satija and Hu).

The gut microbiome is another way through which plant-based diets may decrease the risk of CVDs. The vast community of microbes that reside in the human gut have been shown to metabolize otherwise indigestible food substrates. In turn, this process can significantly influence the human host’s cardiovascular health (De Filippo et al.). The trimethylamine N-oxide (TMAO) pathway is one illustration of this phenomenon. Choline and L-carnitine, which are mostly sourced from animal sources such as red meat, chicken, and fish, are broken down by gut microorganisms. This process then leads to the production of trimethylamine (TMA), which is then further broken down by the liver to ultimately produce TMAO. “TMAO has been associated with a higher risk of cardiovascular events independent of traditional risk factors, and it is postulated that it influences cardiac health through its effects on cholesterol and sterol metabolism, inflammation, and thrombotic and atherosclerotic pathways” (Satija and Hu). Plant-based diets differ from animal-based diets in many additional microbe-dependent metabolic pathways. These include, but are not limited to, enhanced fiber and polyphenol metabolism as well as reduced bile acid and amino acid metabolism. In turn, such plant-based diet pathways have been associated with a lower risk of CVDs as well as an improved cardiovascular risk profile (Hooper et al.).

Furthermore, an important factor that contributes to the onset of CVDs is high cholesterol. “Epidemiological studies have shown a high prevalence of hypercholesterolemia in Western countries (more than 50% of adults have total cholesterol serum levels higher than 5 mmol/L), along with the high incidence of cardiovascular disease and related deaths” (Kahleova et al.). Clinical studies show that for every 1% drop in LDL-cholesterol, the risk of a significant cardiac event, such as a heart attack or stroke, is lowered by approximately 1% (Grundy et al.). Transitioning to plant-based diets can reduce LDL levels significantly. In fact, recent studies estimate that these reductions can range between 30-40% in those with, or at risk of, CVDs (Grundy et al.). This drastic reduction can therefore play a substantial role in disease prevention and management. 

Unfortunately, certain dietary components found in animal diets have been linked to an elevated risk of CVDs. For example, heme iron, which is found primarily in animal meals such as red meat, poultry, and shellfish, has been associated with an increased risk of significantly negative cardiovascular outcomes in multiple prospective cohort studies (Ascherio et al.). The oxidative potential of iron, together with the increased absorption of heme iron, can fuel CVDs in people who do not adhere to a plant-based diet. Other nutrients that are commonly found in meat preservation and processing can also cause CVDs. These nutrients include, but are not limited to, sodium, nitrates, and nitrites. When combined, they may also “...increase risk of cardiovascular outcomes through raised blood pressure, impaired insulin response, and endothelial dysfunction” (Satija and Hu).

Type 2 Diabetes and Plant-Based Diets

Overview

Type 2 diabetes is a leading cause of mortality nationwide. This disease is connected with an increased risk of death, decreased functional status, and higher likelihood of institutionalization in older people. Diabetes problems in the elderly are also common, including myocardial infarction, significant lower limb amputations, end stage renal disease, and vision impairment (McMacken and Shah). A major contributor to insulin resistance is diet, particularly in older, more sedentary populations. The general increased intake of calorie-dense foods, such as fast food, meat and other animal fats, highly refined carbohydrates, and drinks with added sugar is regarded to be a significant factor in the growing incidence of type 2 diabetes across the U.S. and the world (Ley et al.). Large cohort studies show that compared to omnivores and even semi-vegetarians, persons who follow plant-based dietary patterns have a significantly reduced prevalence and incidence of type 2 diabetes. In fact, low body mass indexes (BMIs) that result from plant-based food consumption can protect people against type 2 diabetes (McMacken and Shah). 

Health Benefits and Plant-Based Diets

The Adventist Health Study 2 investigated type 2 diabetes prevalence by diverse eating patterns in a health-conscious population. With each decrease in the consumption of animal products, the prevalence of type 2 diabetes among nearly 61,000 people fell incrementally: from 7.6 percent in non-vegetarians to 6.1 percent in semi-vegetarians to 4.8 percent in pesco-vegetarians to 3.2 percent in lacto-ovo vegetarians to 2.9 percent in vegans (Tonstad et al.). After controlling for BMI and other factors, the benefits of vegan diets persisted, with vegans having half the prevalence of type 2 diabetes compared to non-vegans. The fact that the non-vegans in this cohort consumed meat and poultry only occasionally—once a week or more for non-vegetarians and less than once a week for semi-vegetarians—indicates that even modest increases in the consumption of red meat and poultry may disproportionately raise the risk of type 2 diabetes (Tonstad et al.). 

An additional study of vegetarian men in a cohort of 4,384 Taiwanese Buddhists reinforced these findings. The males in this study had a rate of diabetes that was roughly half that of omnivorous men (McMacken and Shah). It is also important to note that the omnivores in this study mostly consumed plant-based foods, with no fish or meat. This suggests once more that even small amounts of meat can have a substantial impact on whether someone develops type 2 diabetes. Furthermore, The Health Professionals Follow-Up Study, the Nurses’ Health Study, and the Nurses’ Health Study II underscore these findings as well. When the extensive results from these studies were analyzed, they revealed that individuals who most closely followed the healthy plant-based dietary index had a 34 percent reduced chance of being diagnosed with diabetes than those who did not (Rimm et al.). 

Interestingly, the consumption of animal fats and protein have been associated with a rise in type 2 diabetes. In metabolic as well as large cohort studies, the incidence of type 2 diabetes was 22 percent higher over a 12-year period in the highest quintile of animal protein consumption compared to the lowest quintile (it increased by 5 percent for every 10 grams of animal protein consumed) (Rimm et al.). In elderly populations, these findings seem to be more pronounced. “In a geriatric population (ages 65 to 100 years) in Greece, a 5% increase in protein intake from meat and meat products was associated with a 34% greater likelihood of type 2 diabetes even after adjustments for age, gender, obesity, history of hypertension, hyperlipidemia, and other dietary habits. In contrast, protein intake from plant sources offered protection against diabetes” (McMacken and Shah).

A study was also conducted on lean men with type 2 diabetes who were taking insulin. They were placed on a high-carbohydrate, high-fiber diet in order to determine what percentage of the improvement in diabetes prevention was due to weight loss as opposed to dietary changes. If participants lost weight while following a high-fiber diet diet, body weights were simply maintained by having them eat more. The results of this study are important to consider: the average insulin dosage reduced from 26 units on the baseline diet to 11 units on the high-fiber diet (Anderson and Ward). When considered as a whole, this study demonstrates that half of its subjects were able to stop taking insulin, and the remaining half were able to drastically lower their insulin dosages. These findings support the effectiveness of plant-based, low-fat diets to help prevent and perhaps even reverse type 2 diabetes. 

When type 2 diabetes is not addressed, ​​kidney-related illnesses can occur. Fortunately, people who develop kidney diseases may still be able to decrease their negative impacts by following a plant-based diet. In people with chronic kidney disease, “...every 33% increase in plant to total protein consumption was associated with a significant 23% lower mortality risk. To evaluate which foods may be associated with worsening renal disease in diabetic patients, Almeida, et al. obtained a detailed diet history in diabetic patients with and without micro-albuminuria. High intake of protein from animal sources and low intake of polyunsaturated fatty acids, particularly from plant oils, was associated with the presence of micro-albuminuria” (McMacken and Shah). By way of background, albuminuria is a sign of kidney disease. The presence of albuminuria can mean that people have an excessive amount of albumin in their urine since healthy kidneys do not typically allow albumin to pass from blood into urine (National Institute of Diabetes and Digestive and Kidney Diseases). A randomized controlled study showed that a plant-based, dietary intervention can reverse the presence of micro-albuminuria. Among a group of diabetic individuals with macro-albuminuria, animal protein was replaced with soy protein. Interestingly, there was a reduction of macro-albuminuria in the soy protein intervention group (McMacken and Shah).  

A variety of plant-based food habits are suitable for type 2 diabetes control. Specifically, carbohydrates should be obtained from legumes, whole grains, fruits, and vegetables on a daily basis – with a focus on nutrient-dense, high-fiber, low-glycemic-load diets (Rimm et al.). People with diabetes are also advised to follow the general population’s standards for saturated fat, cholesterol, and trans fat intake. Fortunately, plant-based diets tend to automatically adhere to these recommendations. According to the Academy of Nutrition and Dietetics, vegetarian and vegan diets are healthy for all phases of life, from infancy to adulthood, and may help prevent and reverse diabetes. Multiple analyses have been conducted on the relationships between macronutrients and type 2 diabetes prevention. Although the ideal macronutrient balance in type 2 diabetes has not been determined, food sources (e.g., animal vs. plant, refined vs. unprocessed) are as essential as, if not more important than, precise carbohydrate, protein, and fat ratios for controlling this disease (Rimm et al.). 

Limitations

Lack of Plant-Based Food Accessibility

While it is apparent that plant-based diets may have profound beneficial influences on human health, such foods may be inaccessible to economically disadvantaged communities. There are approximately 23.5 million Americans who live in low-income communities that are located more than a mile away from a supermarket (Ver Ploeg et al.). The U.S. Department of Agriculture (USDA) defines food deserts as census tracts that have both low income and low access to supermarkets (USDA). Several studies have shown having access to supermarkets is related to eating healthier diets. “According to the Atherosclerosis Risk in Communities (ARIC) study, for each additional supermarket within a census tract, the number of black and white adults meeting national guidelines for fruit and vegetable consumption was 32% and 11% higher, respectively (Gray et al.). Additional studies have used dietary scores to investigate food environments and overall dietary quality. “In the Multi-Ethnic Study of Atherosclerosis (MESA), compared to those who lived in areas with the highest supermarket density, those who lived in areas with the lowest density of supermarkets were 25% less likely to have a healthy diet” (Gray et al.). 

A statistically significant interaction between food desert and region was detected in the plant-based dietary pattern. Adherence to a plant-based dietary pattern was 15% lower among inhabitants of food deserts compared to residents of non-food deserts outside the south-east (Gray et al.). These research findings are particularly relevant because they studied individuals from a large, countrywide sample size. Moreover, other cross-sectional studies across the U.S. have investigated the connection of food availability and diet, discovering that limited food access is related with a poor diet across all individuals (Moore et al.). 

Aside from geographical proximity to supermarkets, economics also plays a critical role in being able to access plant-based foods. “Food prices have been rising faster than their historical norms and faster than most other goods. Since 2006, the all-item CPI [Consumer Price Index] has risen by 14 percent while the all-food CPI has risen by 20 percent. As a result, households are spending a larger share of their income on food” (Charette et al. 7). Families are forced to make challenging trade-offs when earnings remain constant while the cost of essentials such as food, housing, and transportation increases. The two largest line items in a household budget are housing and transportation expenditures, both of which are difficult to cut since short-term consumption patterns and prices are often set. Yet food is typically purchased over the course of a month. This provides many more opportunities to modify consumption habits in response to altering financial restrictions (Charette et al. 8).

Food preferences tend to change toward less expensive but more calorie-dense meals when salaries decline and family budgets contract. Usually, healthier and more costly meals rooted in high-quality whole grains, vegetables, and fruit are removed from grocery lists during times of financial strain. The most affordable approach to satisfy hunger is often with low-cost, energy-dense carbohydrates, added sugars, and fats. “Lower diet quality separates lower-income from the more affluent Americans. Higher-income households are more likely to buy whole grains, seafood, lean meats, low-fat milk, and fresh vegetables and fruit. Lower-income households purchase more cereals, pasta, potatoes, legumes, and fatty meats” (Drewnowski and Eichelsdoerfer). Calorie-dense sweets and fats are delicious, inexpensive, and widely available. As a result, lower income groups frequently choose them over fresh fruit and other more nutrient-dense diets.

To address this issue, The Thrifty Food Plan was developed by the USDA. It estimates the cost of a balanced diet at various price points: the Low-Cost, Moderate-Cost, and Liberal Food Plans. The Thrifty Food Plan shows the cost of preparing healthy, practical, and cost-effective food at home for a family of four (USDA). The Thrifty Food Plan is used to calculate the quantity of benefits that the Supplemental Nutrition Assistance Program (SNAP) can offer a given household. This plan accounts for “specific amounts of various food categories – such as dark green vegetables, whole fruit and poultry – that together comprise a practical, cost-effective diet that meets dietary guidance” (USDA). Unfortunately, The Thrifty Food Plan has historically resorted to low-cost foods as one method of achieving its goals. In prior versions of The Thrifty Food Plan, most of the calories were derived from oil, shortening and mayonnaise, white bread, sugar, potatoes, and beans. “The only fresh fruit choices were low cost oranges, apples, bananas, and grapes. Although vegetable servings technically met the guidelines, the amounts of fresh tomatoes or lettuce in The TFP were very small” (Drewnowski and Eichelsdoerfer).

The lack of time is a further issue. Throughout history, many American homes possessed at least one member who had available time to shop and cook. Yet changing workplace demographics over the years required more convenience meals. Even with this change, the estimated time needed to buy, prepare, and cook The Thrifty Food Plan items is still longer than the American average (Drewnowski and Eichelsdoerfer). In theory, The Thrifty Food Plan recommendations may be used to develop affordable, nutrient-dense meals. Nevertheless, such meals likely take a significant amount of effort to prepare. Working families can either have lucrative careers outside their homes or adhere to The Thrifty Food Plan recommendations but may not be able to achieve both goals. 

Healthy nutrition extends beyond mere survival and should include convenience – especially for low-income families with rigorous time commitments. More realistic dietary guidelines might benefit from emphasizing nutrient-rich foods that are more efficient to prepare. For example, nutritional profiling approaches can assist in calculating nutrients per unit cost for certain foods. Furthermore, diet optimization approaches, which are comparable to The Thrifty Food Plan framework but are more sensitive to consumption limits, can assist in translating dietary guidelines into food programs for low-income consumers (Masset et al.). 

Consumption Challenges: Nutritional Sufficiency

The nutritional sufficiency of vegetarian diets, particularly vegan diets that fully omit all animal items, can be considered problematic. The bioavailability of certain nutrients, such as iron, zinc, and vitamin A (obtained from carotenoids conversion) is lower in plant foods than in animal foods (Melina et al.). Nevertheless, these nutrients can be obtained in adequate amounts in well-planned vegan diets in consultation with nutritionists. Other nutrients, including vitamins B12 and D, are predominantly found in animal foods; however, using supplements, eating fortified foods, and, in the case of vitamin D, obtaining enough sunshine, can assure appropriate amounts among vegans (Melina et al.). 

For enhanced health, the Academy of Nutrition and Dietetics, the American Heart Association, and the 2015-2020 Dietary Guidelines for Americans all suggest well-designed vegetarian diets. Despite the best efforts of these guidelines, sufficient protein consumption remains a controversial issue. Since proteins are the building blocks of the human body, they are necessary for optimal health and proper functioning of hormones, enzymes, antibodies, and cells, among other biological components. In turn, amino acids are the building blocks of proteins. There are two types of amino acids: necessary amino acids, which must be ingested from food since they are not produced by the body, and non-essential amino acids, which may be produced by the body (Melina et al.). The capacity of food proteins to satisfy the requirements of building key amino acids for tissue maintenance and development may be used to assess nutritional value. The quality of plant proteins has recently come under intense debate when compared to proteins derived from animal sources due to the steady rise in popularity of plant-based foods over the last decade or so.

Some plant proteins, including soy and amaranth, have an amino acid composition and bioavailability that are comparable to eggs. Although there is an increasing amount of plant-based products with highly bioavailable plant proteins, some challenges may arise. Researchers have found that several anti-nutrients, including, but not limited to, phytates, tannins, and saponins, can interfere with the assimilation of protein in the human body (Siegrist et al.). Vegetarians have been found to consume fewer proteins, particularly lysine and methionine amino acids, than omnivores. Other research demonstrates that plant-based protein sources often have lower levels of the amino acids methionine, lysine, tryptophan, and threonine (Melina et al.). To counter these issues, a well-planned and balanced plant-based diet is essential for vegetarians and vegans. Their dietary habits must include multiple amino acids with a variety of plant-based foods. When implemented effectively, this approach may not lead to a protein deficiency (Melina et al.).

Mechanical and thermal pre-processing methods of plant-based foods have also been scrutinized for reducing their nutritional content. These methods include, but are not limited to, blanching, roasting, dehulling, soaking, frying, and sprouting. Interestingly, such techniques can actually be used to minimize anti-nutrients like protease inhibitors, lessen unpalatable flavors, and enhance mouthfeel and color (Siegrist et al.). Some anti-nutrients, however, are quite resilient. For instance, even at 100 °C, phytates cannot be completely eliminated; thus, a fermentation process that generates phytases, which hydrolyze phytates into myo-inositol and phosphate, may be more effective (Melina et al.). In this regard, it is necessary to create plant-based dietary items that are both anti-nutrient-free and include required amino acids. Furthermore, other techniques are being investigated (such as new microbial fermentation methods and the widespread use of microalgae cultivation) that can increase essential nutrients and protein in plant-based foods (Melina et al.).

Consumption Challenges: Personal and Cultural Hesitancy

In addition to their nutritional concerns about plant-based diets, many people tend to view meat as an essential component of their meals on a profoundly personal and/or cultural level. The majority of explanations that individuals provide for eating meat are that doing so is “natural,” “normal,” “essential,” and generally “good” for their health (Piazza et al.). Meat has also been linked to more formal meals such as standard restaurant dinners, where it can be seen as more socially acceptable than meat substitutes. Meat substitutes are more popular in casual settings, such as eating alone or with family on a weekday (Piazza et al.). As a result, meat substitutes are more likely to be accepted by the general public when presented as a healthy option in casual meals.

Conversely, vegetarian and vegan diets tend to be criticized for their inconvenience, including the plant-based foods that they require. These items can be difficult to cook or prepare and they are not always accessible in supermarkets or local grocery stores. Surveys now indicate that many meat eaters are aware of the benefits of eating more vegetables, but these people tend to find vegetarianism and veganism difficult, costly, or unappealing (Piazza et al.). These factors can prohibit the use of vegetarian and/or vegan substitutes for meat, even when the environmental and health advantages of such alternatives are known. When consumers first try plant-based substitutes, they may experience food neophobia, which is defined as a dislike of eating novel or unfamiliar meals (Siegrist et al.). Exposure to unfamiliar and/or processed foods that differ from familiar ones can activate this type of fear. Reduced food phobia and the development of eating habits for a variety of conventional and novel foods may depend on early familiarization during childhood (Siegrist et al.). In order to expose people to plant-based diets, soy, legume, and cereal-based meat replacements may be alternatives since they can mimic the texture and taste of meat.

Indeed, replicating the look, feel, and flavor of animal products in plant-based substitutes is important for helping meat-eaters overcome food neophobia. These consumers tend to choose food alternatives that resemble meat as closely as possible. The most significant factor is flavor since some customers tend to refuse to buy plant-based protein substitutes because they are afraid that they will not enjoy the taste (Piazza et al.). Nevertheless, it is noteworthy that consumers typically regard plant-based substitutes for processed meat products to be more palatable than alternatives for unprocessed meats. These substitutes include, but are not limited to, plant-based hamburgers, sausages, bacon, chicken tenders, turkey breasts, and nuggets. This is probably due to the fact that the textures of these substitutes tend to be simpler to reproduce than those of raw meat (Siegrist et al.). 

These findings suggest that meat substitutes have a better chance of reducing food neophobia if they are presented in a way that is similar to some of the processed meat items described above. In general, plant proteins need to be processed and altered extensively in order to replicate the sensory qualities of meat. Yet this alteration from the original constituents might cause food anxiety among consumers and fuel food neophobia. For many segments of the U.S. population, excessive processing, additional preservatives, and high sodium content are also among the primary deterrents to increasing the intake of plant-based protein alternatives (Siegrist et al.). Limiting these potential drawbacks can help foster an overall willingness to engage in plant-based diets.

Food neophobia can also be reduced by using clear labeling methods on food packages. These labels should include the precise protein source(s) in the ingredients list. This might help increase the likelihood that customers will eat these items. For instance, consumers were more likely to eat insect-based burgers when the ingredients were clearly listed on their labels, as opposed to when they were kept a secret (Piazza et al.). Given the exotic nature of the food, this is a significant finding with widespread applications. Clear and accurate labeling has also recently been discovered to be vital for increasing consumer acceptance of cultured meat nationwide. When people are told in a non-technical manner that cultured meat is produced from animal cells – without having to raise and kill animals – they may be more likely to eat it (Siegrist et al.). 

Plant-based cow’s milk alternatives also face numerous challenges among food neophobic consumers. As with meat consumption, there are multiple taste and sensory difficulties with cow’s milk replacements – and this is especially true with respect to habitual drinkers of cow’s milk. A taste-testing comparison study was conducted on both adults and children who did not typically ingest plant milk. The findings from this study revealed that cow’s milk had consistently outperformed soy-based alternatives (Bus and Worsley). These results also demonstrated that the participants’ reaction to the taste of soy was a main determinant of whether or not they consumed soy products, including soy milk. Consumers reportedly believed that plant-based milk substitutes were typically more environmentally friendly than dairy products – but this factor tended to not outweigh their taste preferences (Bus and Worsley). In addition to the importance of taste, sugar and fat content were critical factors regarding consumer preference for plant-based milk alternatives to cow’s milk. Customers typically preferred beverages with no added sugar or those that were naturally sweetened. The high caloric, lipid, and cholesterol content of cow’s milk fueled a willingness among participants to try plant-based substitutes (Bus and Worsley). In light of these findings, alternatives to cow’s milk should be produced with an emphasis on nutritional composition and taste enhancements without exceeding excessive amounts of sugar and fat content.

There is an additional component of plant-based substitutes for cow’s milk that must be considered. When compared to plant-based cow’s milk replacements, it is generally believed that the production of cow’s milk has a significant negative impact on the environment (Stagnari et al.). Among all plant-based alternatives to cow’s milk, almond milk may be the most troubling product with respect to environmental sustainability. This is because of a number of varied, interconnected factors. For example, researchers have found that the fuel-heavy transportation of almond milk to retail stores, usage of zinc fertilizer, and irrigation requirements can harm the environment (Bus and Worsley). The use of palm oil in plant-based alternatives to cow’s milk is also of grave concern to issues of environmental sustainability. Unfortunately, most palm oil is not produced in accordance with the Roundtable on Sustainable Palm Oil certification standards. As a result, makers of plant-based cow’s milk substitutes should be conscious of the environmental consequences of palm oil when it is used as an ingredient in such goods (Bus and Worsley). 

Consumption Challenges: Environmental Sustainability

Another consumption-related challenge to plant-based diets relates to issues of sustainability. A positive statement about sustainability is included in the Academy of Nutrition and Dietetics’ current position on vegetarian diets. The statement indicates that “...appropriately planned vegetarian, including vegan, diets are healthful, nutritionally adequate, and may provide health benefits for the prevention and treatment of certain diseases. These diets are appropriate for all stages of the life cycle, including pregnancy, lactation, infancy, childhood, adolescence, older adulthood, and for athletes. Plant-based diets are more environmentally sustainable than diets rich in animal products because they use fewer natural resources and are associated with much less environmental damage” (Melina et al.). Granted, meat substitutes and other plant-based items are generally promoted as being less destructive to the environment. Nevertheless, the sustainability benefits of these products are still being analyzed by scientific researchers. 

The research is unambiguous about the reduced environmental impact of producing legumes, although the contribution of legumes to the reduction of greenhouse gas emissions also relies on how the agro-ecosystem is managed (for example, monocropping vs. conservation agriculture) (Stagnari et al.). Additionally, the post-harvest processing of plant-based foods in general may significantly influence pollution levels. The environmental effects of large-scale manufacturing of cultured meat, sometimes referred to as lab meat, synthetic meat, or in-vitro meat, are yet unknown. Moreover, mycoprotein consumption has also been scrutinized. This form of single-cell protein is typically extracted from fungi and intended for human consumption (Stagnari et al.). Despite having a significantly lower land usage than chicken and pig, mycoprotein has been demonstrated to have a greater influence on global warming reduction practices. According to a life cycle assessment study that rigorously compared a significant number of various meat substitutes, cultured meat and mycoprotein may have the highest environmental impact, chicken (sourced from local feed), dairy, and gluten-based substitutes have a medium environmental impact, and insects and soy-based substitutes have the lowest environmental impact (Stagnari et al.).

Compared to animal sources, microalgae need less land to produce the same amount of protein. When producing protein, algae needs roughly 2.5 square meters per kilogram. This is a sharp contrast to the 47-64 square meters per kilogram, 42-52 square meters per kilogram, and 144-258 square meters per kilogram required for pig, poultry, and beef respectively (Stagnari et al.). Another benefit of using microalgae as a meat substitute is that they can remedy the amount of carbon dioxide in the atmosphere. With a carbon dioxide reduction rate of over 90%, which is exceptionally high compared to that of terrestrial plants, microalgae are environmentally advantageous (Bus and Worsley). The potential of mass producing genetically-engineered microalgae has drawn attention, but still requires a thorough assessment by researchers before it can be accurately evaluated.

Unfortunately, there seems to be a widespread low level of understanding among the general public with respect to the environmental costs associated with the production and consumption of meat and its related products. Additionally, some customers believe that the environmental effect of soy products is comparable to that of meat – even though meat production significantly outweighs soy production regarding pollutant emissions (Stagnari et al.). One reason for this misconception is that soy cultivation for cattle feed, which the public erroneously believes to be soy for human consumption, is a significant contributor to deforestation in Brazil. Despite these findings, public organizations, institutions, and NGOs have consistently worked to increase understanding of the environmental effects of meat and other animal products (Bus and Worsley). These organizations include, but are not limited to, People for the Ethical Treatment of Animals, Switch4Good, Engine 2 Plant Strong, and Vegan Action (also known as The Vegan Awareness Foundation).

In recent years, it seems that public perception about the general sustainability benefits of plant-based diets may have become more accurate. As a result, an increasing number of Americans every year is becoming more receptive to transitioning to plant-based food consumption. Different strategies are used to enhance public participation in this area (Stagnari et al.). A plant-based diet called the Planetary Health Diet was suggested by the EAT-Lancet Commission on Food, Planet, and Health. This initiative was widely promoted as a way to feed the world’s expanding population while still allowing food systems to function safely. Moreover, some public schools have embraced the “Meatless Mondays” campaign to reduce meat consumption to improve children's eating habits (Bus and Worsley). It seems that this creative approach has gained a significant amount of attention across states and counties nationwide.

Conclusion

From reductions in chronic diseases to maintaining a healthy body weight, there are multiple benefits of undertaking a plant-based diet. Yet changing dietary habits in the U.S. to boost consumption of plant-based foods necessitates a multidimensional strategy. Food pricing and geographic accessibility are important challenges for many consumers attempting to reconcile positive nutrition with constricting budgets. Diet optimization techniques and increased geographical distribution of plant-based meals can aid in the promotion of inexpensive, tasty, nutrient-rich foods that are part of the mainstream American diet. Furthermore, culturally sensitive and sustainable dietary behavior interventions may be successful techniques to forge healthier eating patterns while protecting the environment. To create nutritional recommendations that are truly applicable to all sectors of American society, these interventions must be implemented by local, state, and federal levels of government. In so doing, U.S. citizens will be on a path toward maximizing their health.

Works Cited 
 

Alcorta, Alexandra, et al. “Foods for Plant-Based Diets: Challenges and Innovations.” Foods, vol. 10, no. 2, 2021, p. 293. Crossref, doi.org/10.3390/foods10020293.

Anderson, J. W., and K. Ward. “High-Carbohydrate, High-Fiber Diets for Insulin-Treated Men with Diabetes Mellitus.” The American Journal of Clinical Nutrition, vol. 32, no. 11, 1979, pp. 2312–21. Crossref, doi.org/10.1093/ajcn/32.11.2312.

Appel, Lawrence J., et al. “A Clinical Trial of the Effects of Dietary Patterns on Blood Pressure.” New England Journal of Medicine, vol. 336, no. 16, 1997, pp. 1117–24. Crossref, doi.org/10.1056/nejm199704173361601.

Ascherio, A., et al. “Dietary Iron Intake and Risk of Coronary Disease among Men.” Circulation, vol. 89, no. 3, 1994, pp. 969–74. Crossref, doi.org/10.1161/01.cir.89.3.969.

Bus, AEM, and A. Worsley. “Consumers’ Sensory and Nutritional Perceptions of Three Types of Milk.” Public Health Nutrition, vol. 6, no. 2, 2003, pp. 201–08. Crossref, doi.org/10.1079/phn2002417.

Charette, Allison, et al. “Food at Home: Affordable Housing as a Platform to Overcome Nutritional Challenges.” Annie E. Casey Foundation, 2014, assets.aecf.org/m/resourcedoc/Enterprise-FoodatHome-2014.pdf.

Cory, Hannah, et al. “The Role of Polyphenols in Human Health and Food Systems: A Mini-Review.” Frontiers in Nutrition, vol. 5, 2018. Crossref, doi.org/10.3389/fnut.2018.00087.

Crowe, Francesca L., et al. “Risk of Hospitalization or Death from Ischemic Heart Disease among British Vegetarians and Nonvegetarians: Results from the EPIC-Oxford Cohort Study.” The American Journal of Clinical Nutrition, vol. 97, no. 3, 2013, pp. 597–603. Crossref, doi.org/10.3945/ajcn.112.044073.

Drewnowski, Adam, and Petra Eichelsdoerfer. “Can Low-Income Americans Afford a Healthy Diet?” Nutrition Today, vol. 44, no. 6, 2009, pp. 246–49. Crossref, doi.org/10.1097/nt.0b013e3181c29f79.

Filippo, Carlotta de, et al. “Impact of Diet in Shaping Gut Microbiota Revealed by a Comparative Study in Children from Europe and Rural Africa.” Proceedings of the National Academy of Sciences, vol. 107, no. 33, 2010, pp. 14691–96. Crossref, doi.org/10.1073/pnas.1005963107.

Gray, Marquita S et al. “The Association between Residence in a Food Desert Census Tract and Adherence to Dietary Patterns in the REGARDS Cohort.” Food and public health vol. 8,4 (2018): 79-85.

Grundy, Scott M., et al. “Implications of Recent Clinical Trials for the National Cholesterol Education Program Adult Treatment Panel III Guidelines.” Circulation, vol. 110, no. 2, 2004, pp. 227–39. Crossref, doi.org/10.1161/01.cir.0000133317.49796.0e.

Hooper, Lora V., et al. “How Host-Microbial Interactions Shape the Nutrient Environment of the Mammalian Intestine.” Annual Review of Nutrition, vol. 22, no. 1, 2002, pp. 283–307. Crossref, doi.org/10.1146/annurev.nutr.22.011602.092259.

Kahleova, Hana, et al. “Cardio-Metabolic Benefits of Plant-Based Diets.” Nutrients, vol. 9, no. 8, 2017, p. 848. Crossref, doi.org/10.3390/nu9080848.

Ley, Sylvia H., et al. “Prevention and Management of Type 2 Diabetes: Dietary Components and Nutritional Strategies.” The Lancet, vol. 383, no. 9933, 2014, pp. 1999–2007. Crossref, doi.org/10.1016/s0140-6736(14)60613-9.

Lozano, Rafael, et al. “Global and Regional Mortality from 235 Causes of Death for 20 Age Groups in 1990 and 2010: A Systematic Analysis for the Global Burden of Disease Study 2010.” The Lancet, vol. 380, no. 9859, 2012, pp. 2095–128. Crossref, doi.org/10.1016/s0140-6736(12)61728-0.

Martínez-González, Miguel A., et al. “A Provegetarian Food Pattern and Reduction in Total Mortality in the Prevención Con Dieta Mediterránea (PREDIMED) Study.” The American Journal of Clinical Nutrition, vol. 100, no. suppl_1, 2014, pp. 320S-328S. Crossref, doi.org/10.3945/ajcn.113.071431.

Masset, Gabriel, et al. “Diet Optimization Methods Can Help Translate Dietary Guidelines into a Cancer Prevention Food Plan.” The Journal of Nutrition, vol. 139, no. 8, 2009, pp. 1541–48. Crossref, doi.org/10.3945/jn.109.104398.

McManus, Katherine M. D. “What Is a Plant-Based Diet and Why Should You Try It?” Harvard Health, 16 Nov. 2021, www.health.harvard.edu/blog/what-is-a-plant-based-diet-and-why-should-you-try-it-2018092614760.

McMacken, Michelle, and Sapana Shah. “A Plant-Based Diet for the Prevention and Treatment of Type 2 Diabetes.” Journal of Geriatric Cardiology : JGC vol. 14,5 (2017): 342-354. doi:10.11909/j.issn.1671-5411.2017.05.009

Melina, Vesanto, et al. “Position of the Academy of Nutrition and Dietetics: Vegetarian Diets.” Journal of the Academy of Nutrition and Dietetics, vol. 116, no. 12, 2016, pp. 1970–80. Crossref, doi.org/10.1016/j.jand.2016.09.025.

Micha, Renata, et al. “Association Between Dietary Factors and Mortality From Heart Disease, Stroke, and Type 2 Diabetes in the United States.” JAMA, vol. 317, no. 9, 2017, p. 912. Crossref, doi.org/10.1001/jama.2017.0947.

Moore, L. V., et al. “Associations of the Local Food Environment with Diet Quality--A Comparison of Assessments Based on Surveys and Geographic Information Systems: The Multi-Ethnic Study of Atherosclerosis.” American Journal of Epidemiology, vol. 167, no. 8, 2008, pp. 917–24. Crossref, doi.org/10.1093/aje/kwm394.

National Institute of Diabetes and Digestive and Kidney Diseases. “Albuminuria: Albumin in the Urine.” National Institute of Diabetes and Digestive and Kidney Diseases, 9 Dec. 2021, www.niddk.nih.gov/health-information/kidney-disease/chronic-kidney-disease-ckd/tests-diagnosis/albuminuria-albumin-urine#:%7E:text=Clinical%20Trials-,What%20is%20albuminuria%3F,the%20blood%20into%20the%20urine.

Piazza, Jared, et al. “Rationalizing Meat Consumption. The 4Ns.” Appetite, vol. 91, 2015, pp. 114–28. Crossref, doi.org/10.1016/j.appet.2015.04.011.

Ploeg, M. ver, et al. “Access To Affordable and Nutricious Food.” USDA.Gov, 2014, www.ers.usda.gov/webdocs/publications/42711/12716_ap036_1_.pdf.

Rimm, Eric B., et al. “Plant-Based Dietary Patterns and Incidence of Type 2 Diabetes in US Men and Women: Results from Three Prospective Cohort Studies.” PLOS Medicine, edited by Steven C Moore, vol. 13, no. 6, 2016, p. e1002039. Crossref, doi.org/10.1371/journal.pmed.1002039.

Satija, Ambika, and Frank B. Hu. “Plant-Based Diets and Cardiovascular Health.” Trends in Cardiovascular Medicine, vol. 28, no. 7, 2018, pp. 437–41. Crossref, doi.org/10.1016/j.tcm.2018.02.004.

Siegrist, Michael, et al. “Perceived Naturalness and Evoked Disgust Influence Acceptance of Cultured Meat.” Meat Science, vol. 139, 2018, pp. 213–19. Crossref, doi.org/10.1016/j.meatsci.2018.02.007.

Stagnari, Fabio, et al. “Multiple Benefits of Legumes for Agriculture Sustainability: An Overview.” Chemical and Biological Technologies in Agriculture, vol. 4, no. 1, 2017. Crossref, doi.org/10.1186/s40538-016-0085-1.

The US Department of Agriculture. “Thrifty Food Plan.” USDA.Gov, www.fns.usda.gov/snap/thriftyfoodplan. Accessed 4 Aug. 2022.

Tonstad, Serena, et al. “Type of Vegetarian Diet, Body Weight, and Prevalence of Type 2 Diabetes.” Diabetes Care, vol. 32, no. 5, 2009, pp. 791–96. Crossref, doi.org/10.2337/dc08-1886.

World Health Organization. “Cardiovascular Diseases (CVDs).” WHO, 11 June 2021, www.who.int/news-room/fact-sheets/detail/cardiovascular-diseases-(cvds).

Yokoyama, Yoko, et al. “Vegetarian Diets and Blood Pressure.” JAMA Internal Medicine, vol. 174, no. 4, 2014, p. 577. Crossref, doi.org/10.1001/jamainternmed.2013.14547.