Part 2: Inflammation
A study completed in 2018 revealed that a whole-food plant-based vegan diet significantly reduces inflammation while the diet recommended by the American Heart Association for patients with cardiovascular disease does not (1).
Why is this important? Because what you eat can have an enormous effect on heart health. This makes it imperative that heart patients be given the very best advice when it comes to optimal food choices for cardiovascular health. And keeping inflammation to a minimum is a key target. Chronic inflammation is a known causal factor of most of the chronic diseases associated with aging in modern human beings. In fact inflammation level is now used as an indicator of the degree of risk for cardiovascular disease. Information from studies such as this one confirm that one of the best ways to decrease inflammation is to avoid eating even small amounts of animal-sourced foods.
The differences between a whole-food plant-based vegan diet and the American Heart Association (AHA) diet appear to be minor, however they are of substantial importance when it comes to the health of the human body (2).
A whole-food plant-based diet encompasses only plant-sourced foods. All foods sourced from animals as well as any foods that have been processed or refined are completely avoided.
The American Heart Association (AHA) diet emphasizes fruits, vegetables and whole grains which of course are the basis of a whole-food plant-based diet. But it also allows some fish, small amounts of lean meats, non-fat or low-fat dairy products and polyunsaturated and monounsaturated plant oils (2). Regrettably the effect of these extra foods is of major consequence to cardiovascular health.
It is interesting to have a quick look at the study itself (1). This study was rigorous in its method and execution, using a prospective, randomized, open-label, blinded end-point study design. The 100 participants, all of whom were suffering from coronary artery disease, were randomized to either a whole-food plant-based vegan diet or to the AHA-recommended diet for a period of eight weeks. Participants were provided with their weekly groceries along with suggested menus, tools for measuring portion size and on-going consultation with the study dietitian. Participants were monitored for adherence to their diet using measurement of blood and urine trimethylamine-N-oxide levels to quantify the ingestion of animal protein. (Trimethylamine-N-oxide is a blood vessel-damaging nutrient that results from consuming meat, poultry, fish, eggs and milk products.) The primary result the researchers were following was the inflammation level of participants. This was determined through measurement of hsCRP (high sensitivity C-reactive protein). The higher the hsCRP, the great the inflammation.
Results showed a 32% lower concentration of hsCRP in those eating a whole-food plant-based diet compared to those eating the AHA diet. After adjustment for other factors that affect inflammation such as age, race, waist circumference, presence of diabetes mellitus, and prior myocardial infarction, there remained a very significant 33% lower concentration of hsCRP with the whole-food plant-based eaters than in those consuming the AHA diet. In addition the participants eating whole-food plant-based were more satisfied with their food with 94% of them sticking to their diet over the whole 8 weeks of the study compared to only 70% of those following the AHA diet.
The fact that eating animal-sourced foods increases inflammation is an established one supported by substantial scientific study over many years. Here are some examples of these studies. In 2013 the association between dietary patterns and inflammation was examined through a review of 46 previous studies. It was found that meat-based patterns were associated with increased inflammation while vegetable- or fruit-based patterns were associated with lower inflammation (3). In 2014 another study revealed that the greater the intake of total, unprocessed, and processed red meat, the higher the level of plasma hsCRP indicating an increased level of inflammation. Additionally, substituting red meat with protein from another source such as legumes, nuts, fish or poultry, resulted in lower chronic inflammation (4). A prospective cohort study (a study that follows a similar group of people over time) that included a low-fat whole-foods plant-based diet, exercise, stress management and group support demonstrated significant decreases in C-reactive protein concentrations (5). A 2017 analysis found that eating a plant-based diet resulted in a 42% drop in the risk of heart failure over the four years of the study compared to those eating fewer plant foods (6). Inflammation is a key factor in the development of heart failure (7).
What does all this tell us? That moderation when it comes to our food choices is not enough. It has been theorized that it is not necessary to become completely plant-based to gain benefits from diet changes; that just cutting down on the amount of meat, eggs and dairy eaten might be enough. And indeed the more plants a person eats the better off they likely are. However if you want to really make a difference in your well-being and enjoy all the healthy benefits that plants offer then avoiding all food products sourced from animals is the only way to go. Studies like this one help to make this point clear.
1 Shah, B., Newman, J., Woolf, K., Ganguzza, L, Guo, Y., Fisher, E.A., Allen, N., Hazen, S.L., Larigakis, J., Zhong, J., Gianos, E., Ujueta, F., Slater, J. Anti-inflammatory Effect of Whole-Food Plant-Based Vegan Diet vs the American Heart Association – Recommended Diet in Patients With Coronary Artery Disease: The Randomized EVADE CAD Trial. Circulation June 9, 2018; 136 (No. suppl 1). https://purjesfoundation.org/wp-content/uploads/Final-paper.pdf
3 Barbaresko, J., Koch, M., Schulze, M.B., Nöthlings, U. Dietary pattern analysis and biomarkers of low-grade inflammation: a systematic literature review. Nutr Rev. 2013 Aug;71(8):511-527.
4 Ley, S.H., Sun, Q., Willett, W.C., Eliassen, A.H., Wu, K., Pan, A., Grodstein, .F, Hu, F.B. Associations between red meat intake and biomarkers of inflammation and glucose metabolism in women. Am J Clin Nutr. 2014 Feb; 99(2):352-360.
5 Chainani-Wu, N., Weidner, G., Purnell, D.M., Frenda, S., Merritt-Worden, T., Pischke, C.,
Campo, R., Kemp, C., Kersh, E.S., Ornish, D. Changes in emerging cardiac biomarkers after an intensive lifestyle intervention. Am J Cardiol. 2011;108:498–507.
7 Shirazi, L.F., Bissett, J.1, Romeo, F., Mehta, J.L. Role of Inflammation in Heart Failure. Curr Atheroscler Rep. 2017 Jun;19(6):27.