The Portfolio Diet for Cardiovascular Disease Risk Reduction: An Evidence Based Approach to Lower Cholesterol through Plant Food Consumption

By Wendy Jenkins, Amy Jenkins, Alexandra Jenkins and Caroline Brydson

The Portfolio Diet for Cardiovascular Disease Risk Reduction: An Evidence Based Approach to Lower Cholesterol through Plant Food Consumption examines the science of this recommended dietary approach to reduce cholesterol in addition to other risk factors for cardiovascular disease. With a thorough examination into the scientific rationale for the use of this diet, discussions are included on the experimental findings both for the diet as a whole, and its four principle food components: nuts and seeds, plant based protein, viscous fibers, and plant-sterol-enriched foods. Environmental and ethical considerations of the diet are also discussed, showing the ramifications of food choice on health and beyond. Referenced with data from the latest relevant publications and enhanced with practical details (including tips, dishes, and menus), the reader is enabled to meet the goals of cholesterol lowering and cardiovascular disease risk reduction while also taking the health of the planet into consideration.

• Provides the scientific basis for the selection of the foods included in the Dietary Portfolio and the experimental evidence demonstrating cholesterol lowering and cardiovascular risk factor reduction
• Provides an understanding of the current guidelines for lowering cholesterol and other risk factors of cardiovascular disease, explaining how the Dietary Portfolio effects these components and compares to other diet based approaches
• Provides a holistic view of the Dietary Portfolio by investigating issues of sustainability and ethics in the food system
• Allows readers to acquire the skills to successfully construct a potent cholesterol-lowering diet
• Includes tips, recipes and meal planning aids

• Language: English
• Publisher: Academic Press
• Release date: Nov 24, 2019
• ISBN: 9780128105115

Wendy Jenkins

Wendy Jenkins, BSc, and MSc candidate, has worked extensively to merge the fields of nutrition and environmental science. She has done this primarily through her study of the interaction between diet, health and environmental sustainability. Her work has led her to the promotion of plant based foods in both an academic setting and through recipe development. In her previous studies at the University of Guelph in the Environmental Biology honors program in Canada and her current postgraduate studies in nutrition at Wageningen University, The Netherlands, she has worked with the aim of maximizing both health and sustainability of dietary decisions. She has also worked under the guidance of chef Sara Harrel, owner of Veg Company and developer of the certificate in Vegetarian Culinary Arts at George Brown College Centre for Culinary Arts, Toronto, Canada. Through this work Wendy has been able to further develop her skills in plant based cuisine and recipe development, providing the tools to create healthy, sustainable and enjoyable food.

Book preview

Yiang

Introduction

Let food be thy medicine and medicine be thy food.

Hippocrates 470–340 BC, Greece

We would like to welcome you to the Dietary Portfolio. In our book, we have tried to give you the reasons why following the Portfolio Diet will improve the health of you, your family and the planet. The Dietary Portfolio is an option for those who cannot or do not wish to be on cholesterol-lowering medications or wish to improve the effectiveness or reduce the dose of CVD-related medications. As the Portfolio Diet reduces Low-density lipoprotein (LDL-C) and other CVD risk factors, it may also be helpful for those who want to be proactive and avoid the development of CVD over their lifetime. Ultimately, this diet is for anyone who wants to follow a healthier, more sustainable and compassionate diet. It is unfortunately not suitable for those with sitosterolemia (a rare condition affecting plant sterol absorption). As always, it is a good idea to check with your healthcare provider before starting a new diet.

The Portfolio diet stands out from other popular diets as it is an evidence-based diet with its ability to reduce CVD risk factors scientifically tested [1–3]. Since its development, it has been promoted internationally and is recommended by the Canadian Cardiovascular Society (CCS) [4], the European Atherosclerosis Society (EAS) [5], and Heart UK [6]. The Portfolio diet is most well known for its ability to reduce LDL-C levels [7,8]. This type of cholesterol (LDL-C) is known to contribute to the formation of fatty arterial plaque, which can eventually lead to blocked arteries, and increase the risk of heart attack and stroke.

In clinical trials, the Portfolio diet, in the context of a plant-based diet, were able to reduce LDL-C by 28%, an amount equivalent to the reductions seen by those taking Lovastatin, a statin drug used to lower cholesterol [3]. When health outcomes were evaluated using the Framingham risk equation, which uses patient history and health indicators like blood pressure, weight, and cholesterol, to calculate the risk of developing coronary heart disease (CHD), the risk for those consuming the Portfolio diet was reduced by 25%. This research was the first to demonstrate that a dietary intervention could reduce LDL-C levels to a similar extent as a first-generation statin. Longer-term Portfolio diet studies have been conducted in several locations across Canada. Unlike the first study, these studies asked the participants to find and purchase the Portfolio foods themselves. These studies have also had very positive results, with reductions in LDL-C ranging from 13% to 14% [2]. These reductions were seen even though the different locations had very different food environments where access to portfolio foods varied. Unsurprisingly, this study found that individuals in areas with easy access to foods that support the Portfolio diet like fresh fruit, vegetables, and a wide selection of meat analogs were better able to adhere to the Portfolio diet and saw larger reductions in CHD risk. The impact that different food environments can make on the success of a diet is one of the main reasons for this book. Although it’s impossible to change the food environment you live in, we hope this book can help you better navigate your current environment by providing not only the scientific evidence behind the diet, but also tips, tricks, guidance, and easy-to-prepare recipes.

The protective effects of the Portfolio diet are not limited to its effects on LDL-C. Other beneficial effects of the Portfolio diet include the reduction of inflammatory biomarkers like c-reactive protein (CRP), increased levels of which have been associated with heart disease and cancer [9,10]; improved glycemic control or lower blood sugar levels after a meal; an increase in the amount of high-density lipoprotein cholesterol (HDL-C) or good cholesterol, in relation to LDL-C, the bad cholesterol, and finally blood pressure reductions similar to those seen in DASH diet, the gold standard for dietary blood pressure reduction [2,11]. Together these factors have found to contribute to a reduced risk of CVD and have shown potential in the management of type 2 diabetes [12].

The Portfolio diet is composed of four main pillars. Each of the four pillars work in tandem to reduce risk factors. The four pillars of the Portfolio diet are

1.Plant sterols, found in enriched margarine, juices and supplements.

2.Viscous fiber, which is found in foods such as oats, barley, okra, and psyllium.

3.Nuts and seeds like almonds, walnuts, and sunflower seeds.

4.Plant-based protein found in foods such as tofu, soy milks, meat analogs and legumes.

The Portfolio diet was developed with the intention of acting like a stock portfolio where assets, or in this case, foods, can be collected and added as new scientific evidence emerges. In this way, it is a dynamic and ever-evolving diet. It is situated in the context of a plant-based diet for health, environmental, and ethical reasons. Users of this diet are encouraged to consume foods in the context of a plant-based diet, which contains no animal products. It is recommended to try to minimize the consumption of animal products for best results. In addition to health, sustainability of diet will also be improved with increased adherence to a plant-based diet. As the Portfolio diet consists of a variety of foods, which can be used in a variety of dishes, it can easily adapt to fit personal tastes, as well as a variety of cultural cuisines. This portfolio of foods provides a healthy base ready to be customized. For a short summary on how to incorporate the Portfolio diet into your lifestyle see infographic on the following pages, which was developed in collaboration with the original Portfolio researchers at St. Michael’s Hospital in Toronto.

References

[1] Jenkins D.J.A., Kendall C.W.C., Faulkner D.A., Kemp T., Marchie A., Nguyen T.H., et al. Long-term effects of a plant-based dietary portfolio of cholesterol-lowering foods on blood pressure. Eur J Clin Nutr. 2008;62(6):781–788. doi:10.1038/sj.ejcn.1602768.

[2] Jenkins D.J.A., Jones P.J.H., Lamarche B., Kendall C.W.C., Faulkner D., Cermakova L., et al. Effect of a dietary portfolio of cholesterol-lowering foods given at 2 levels of intensity of dietary advice on serum lipids in hyperlipidemia: a randomized controlled trial. J Am Med Assoc. 2011;306(8):831–839. doi:10.1001/jama.2011.1202.

[3] Jenkins D.J.A., Kendall C.W.C., Marchie A., Faulkner D.A., Wong J.M.W., de Souza R., et al. Direct comparison of a dietary portfolio of cholesterol-lowering foods with a statin in hypercholesterolemic participants. Am J Clin Nutr. 2005;81(2):380–387.

[4] Anderson T.J., Grégoire J., Pearson G.J., Barry A.R., Couture P., Dawes M., et al. 2016 Canadian Cardiovascular Society Guidelines for the management of dyslipidemia for the prevention of cardiovascular disease in the adult. Can J Cardiol. 2016;32(11):1263–1282. doi:10.1016/j.cjca.2016.07.510.

[5] Catapano A.L., Graham I., De Backer G., Wiklund O., Chapman M.J., Drexel H., et al. 2016 ESC/EAS guidelines for the management of dyslipidaemias. Rev Esp Cardiol. 2017;70(2):115. doi:10.1016/j.rec.2017.01.002.

[6] Heart U.K. The Portfolio Diet. Retrieved from https://heartuk.org.uk/files/uploads/documents/huk_fs_d01_theportfoliodiet.pdf. 2006.

[7] Gigleux I., Jenkins D.J.A., Kendall C.W.C., Marchie A., Faulkner D.A., Wong J.M.W., et al. Comparison of a dietary portfolio diet of cholesterol-lowering foods and a statin on LDL particle size phenotype in hypercholesterolaemic participants. Br J Nutr. 2007;98(6):1229–1236. doi:10.1017/S0007114507781461.

[8] Lamarche B., Desroches S., Jenkins D.J.A., Kendall C.W.C., Marchie A., Faulkner D., et al. Combined effects of a dietary portfolio of plant sterols, vegetable protein, viscous fibre and almonds on LDL particle size. Br J Nutr. 2004;92(4):657–663.

[9] Lopez-Garcia E., Schulze M.B., Meigs J.B., Manson J.E., Rifai N., Stampfer M.J., et al. Consumption of trans fatty acids is related to plasma biomarkers of inflammation and endothelial dysfunction. J Nutr. 2005;135(3):562–566. doi:10.1093/jn/135.3.562.

[10] Lu H., Ouyang W., Huang C. Inflammation, a key event in cancer development. Mol Cancer Res. 2006;4(4):221–233. doi:10.1158/1541-7786.MCR-05-0261.

[11] Jenkins D.J.A., Jones P.J., Frohlich J., Lamarche B., Ireland C., Nishi S.K., et al. The effect of a dietary portfolio compared to a DASH-type diet on blood pressure. Nutr Metab Cardiovasc Dis. 2015;25(12):1132–1139. doi:10.1016/j.numecd.2015.08.006.

[12] Salas-Salvado J., Bullo M., Babio N., Martinez-Gonzalez M.A., Ibarrola-Jurado N., Basora J., et al. Reduction in the incidence of type 2 diabetes with the Mediterranean diet: results of the PREDIMED-Reus nutrition intervention randomized trial. Diabetes Care. 2011;34(1):14–19. doi:10.2337/dc10-1288.

Chapter 1

The Power of Diet in CVD Risk Factor Reduction

Abstract

This chapter investigates how factors like body-weight, blood pressure, and blood lipid levels can contribute to the developof cardiovascular disease (CVD) and what qualifies an individual to be at risk. These factors were chosen as the focus of this chapter due to their extensive association with CVD. The effectiveness of the Portfolio diet in reducing these risk factors, is compared to other diets, including The Mediterranean diet, the Okinawan diet, the Nordic diet, a low glycemic index (GI) diet the Dietary Approaches to Stop Hypertension (DASH) diet. Many of these diets were developed to mimic the traditional diets of populations known to have low levels of these risk factors and the incidence of CVD. In contrast, the Portfolio diet was developed by combining components known to individually reduce the risk of CVD and situating them in the context of a healthy eating pattern. These compoinclude nuts, viscous fiber, plant sterols, and soy protein. When combined the effect on risk factor reduction is much greater than any component individually. As some of these components are also found in the other diets which we discussed, this chapter reviews the overlap in risk reduction with other evidence-based