Globally, the incidence of end-stage diseases that are caused by chronic inflammation are on the rise. Many of the foods that are consumed daily in a typical Western diet, including processed foods, dairy, meat, and/or trans fats, cause chronic inflammation, which lead to life-threatening diseases such as cardiovascular disease, diabetes, asthma and stroke. There is a growing body of clinical evidence that clearly demonstrates that switching to a plant-based diet can greatly reduce your chances of developing one of these end-stage diseases, although this does not mean that you have to give up meat or animal products altogether. In fact, the current landscape of debate on veganism, vegetarianism, and meat-heavy diets is muddied by polemics, making it difficult for the average person to make an informed choice. So what does the science actually say about the effects of plant-based diets on chronic inflammation and its associated diseases?

Diseases caused by chronic inflammation are globally on the rise

The clearest evidence, according to the World Health Organization, is that cardiovascular disease remains the leading cause of death globally, claiming an estimated 17.9 million lives each year. Heart attacks and strokes account for four out of five deaths from cardiovascular disease, and a third of these deaths occur in people under the age of 70. In the United States, cardiovascular disease is the leading cause of death for men, women, and most races and ethnic groups, with an incidence of one death every 36 seconds and 655, 000 deaths every year. This amounts to roughly 1 in every 4 people dying from cardiovascular disease annually. The figures for Canada are somewhat better but still high; there, roughly 1 in 12 Canadian adults (about 2.4 million) have been diagnosed with heart disease as of 2017, with 193 deaths per 100,000 Canadians as of 2018. The World Heart Federation records that non-communicable diseases, including cardiovascular diseases, account for an estimated 89 % of all adult deaths in the UK, and among these, 31% are attributable to cardiovascular disease. Daily, about 425 people die of cardiovascular disease in the UK. The populations of Mexico, Russia, and China also suffer from a high incidence of from cardiovascular disease, with 20% of all deaths in Mexico, 29.4% in Russia, and 87% of deaths in China from non-communicable diseases, of which 45% of these resulted from cardiovascular disease.

In addition to cardiovascular diseases, the global incidence of diabetes, stroke, and asthma have increased over the past four to five years. According to the World Health Organization, an estimated 425 million people worldwide suffer from diabetes, and this disease killed about 1.6 million people in 2016 alone. The number of diabetics worldwide is forecast to rise to 629 million by 2045 if the current trajectory of new cases holds steady. The WHO also estimates that around 15 million people worldwide suffer strokes each year, with 5 million among them dying from this disease and another 5 million being rendered permanently disabled. Finally asthma, which is the most common non-communicable disease among children, has a lower mortality rate than these other chronic diseases. Among the 339 million sufferers with asthma, less than 420,000 per year – mostly elderly – died of complications from it in 2016, and most of those deaths occurred in low - and middle-income countries and communities.

Plant-based diets can they help reduce chronic inflammation

Can switching to a vegan or vegetarian diet eliminate chronic inflammation?

Although the evidence shows that switching to a plant-based diet can greatly decrease chronic inflammation and thus reduce your risk of developing one of the end-stage diseases associated with it, it doesn’t necessarily involve becoming a vegan or vegetarian to reap these benefits. In fact, the evidence on meat-heavy diets suggests that eating meat in itself doesn’t cause or exacerbate inflammation, but that doesn’t mean that a diet that is meat-heavy is healthy for you.

A vegan diet is one in which all animal products have been cut out: vegans don’t eat eggs, dairy products, or even honey. Most vegans will even avoid wearing anything made from animal products, such as fur and leather, and many will try to avoid actions in their day-to-day lives that cause harm or suffering to animals. The vegan diet is widely regarded to be better for the planet than those that include animal products, but not all plant-based foodstuffs have a small environmental footprint: the agricultural practices (including production, transportation, and storage) associated with some fruits, vegetables, and legumes (such as avocados, almonds, and cashews) require large amounts of resources to produce, or may be linked to deforestation (such as cocoa and palm oil). Moreover, vegans may experience health problems related to a lack of protein and certain other vitamins and minerals that are more easily absorbed from animal products. Pursuing a vegan diet can be worthwhile, but it will take a lot of effort to make sure you aren’t undermining your health or contributing to environmental problems.

There are several varieties of vegetarian diet, including, vegan, lacto-ovo vegetarian (i.e. consuming eggs and dairy products), pesco-pollo vegetarians (i.e. consuming seafood and poultry), pescatarians (i.e. consuming seafood) and flexitarians (i.e. mostly plant-based foods with occasional consumption of small amounts of meat). In many studies, vegetarians score much better than meat-eaters in terms of health outcomes ranging from blood pressure to weight. This is, however, due to the fact that vegetarians tend to make healthier eating and lifestyle choices altogether, such as minimizing their consumption of moderately- and highly-processed foods, and following a diet that contains a variety of the following food groups: fruits and vegetables, protein-rich foods, whole grains, beans and legumes and starchy tubers, and nuts and ‘healthy’ fats like olive oil.

On the whole, studies have demonstrated that vegan and vegetarian diets, when pursued carefully and with other healthy lifestyle choices such as avoiding or minimizing highly processed foods, do greatly reduce chronic inflammation.

What about meat-based diets? Are they really that bad?

Meat-based diets have come under a lot of fire in recent decades, both because of the perception that they are unhealthy and because of the environmental impact of large commercial animal husbandry practices. The claim that meat causes cancer is apparently overblown, and the scientific evidence does not support this conclusion; in fact. While it is true that meat-based food systems require more resources of energy, land, and water than plant-based diets, and that in this sense, a plant-based diet is more sustainable than the average American meat-based diet, this does not translate into the equation that eating meat is inherently unhealthy, or that it is destroying the environment.

On the contrary, existing studies have shown that the Paleo diet, which includes vegetables, fruits, nuts, roots, meat, and organ meats, has beneficial health effects. In one study of 25 participants published in 2015 in the Journal of Gastrointestinal and Liver Diseases, in which 14 were on the Paleo diet and 10 were on a diet based on recommendations from the American Diabetes Association (ADA), both groups had improved metabolic indicators, but the Paleo group had greater benefits in terms of blood glucose control and lipid profile. Other meat-based diets, such as the Carnivore Diet, which excludes foods other than meat, fish, and animal products like eggs and dairy, were associated with poor health outcomes.

The data on meat, therefore, is mixed, and the problems with meat-based diet seem to be associated more with the fact that people who eat meat-based diets tend to make unhealthy eating and lifestyle choices, including eating highly processed meat products (such as jerky, hot dogs, or lunch meat, which contain several potentially carcinogenic compounds) and not eating enough fruits and vegetables. It is for that reason that meat-based diets are associated with a higher incidence of chronic inflammation.

Science confirms these three things…

There are three things the science confirms about how plant-based diets can reduce chronic inflammation and its associated end-stage diseases.:

One, eating more plants and less animal protein correlates with reduced risk of coronary heart diseases and diabetes. This is also likely because people who follow a mostly plant-based diet tend to engage in other behaviors that are characteristic of a healthy lifestyle such as exercising more, eating smaller portions, and minimizing or avoiding highly processed foods.

Two, plant-based diets correlate with longevity in older adults. In other words, plant-based diets (and the presumed healthier lifestyle choices that tend to go along with them) help us to not only live longer lives, but live longer lives that are healthier, more energetic and of an overall higher quality.

Three, the quality of plants you eat is very important. For example, fruits, vegetables and whole grains have been proven to lower the risk of diabetes. Consuming nuts, vegetables and soy products on a regular basis reduces the risk factors for stroke (even processed soy milk, which according to Chinese medical studies, does not seem to have the same kinds of negative health effects as other processed foods). Finally, consuming beans regularly has been shown to reduce the incidence of bad cholesterol and cardiovascular disease.

Overall, plant-based diets have been clinically proven to have beneficial health outcomes. This doesn’t mean that you need to become vegan or fully vegetarian to reap these benefits, however. Instead, controlling the proportion of plant-based to animal-based products seems to be key to greatly reducing your risk for developing chronic inflammation and its associated end stage diseases.