Topic of the Month

Three Pillars of Heart Health – How Nutrition Plays a Role

March 13, 2017

By Julia Bird

Modern medicine has made an enormous contribution to treating cardiovascular diseases. Even so, they remain the leading cause of death globally, in most countries in the world {McAloon, 2016 #1}(1){McAloon, 2016 #1}{McAloon, 2016 #1}. Nutrition is one contributor to cardiovascular disease that individuals can control, along with exercising regularly, maintaining a healthy weight and not smoking. In fact, nutrition has been identified as one of the key factors in cardiovascular disease rates among countries in Europe, for example.  Different components in foods influence the three main influencers of cardiovascular disease: blood pressure, the blood lipid profile and blood flow.

Pillar No. 1 – Blood Pressure

Blood pressure is a measure of the force of the blood being pumped through the arteries and is determined by both the amount of blood being pumped and the resistance to pressure in the arteries. High blood pressure is a dangerous condition that has no clear symptoms and can easily go unnoticed for many years. When high blood pressure occurs, small blood vessels in the body are damaged, including those in important organs such as the heart and kidneys. The high blood pressure can also force a balloon-like bulge into artery or blood vessel walls that can affect organs’ functions, or even burst. Arteries that are more elastic can cope better with the normal changes in blood pressure that occur throughout the day.

The Dietary Approaches to Stop Hypertension (DASH) diet was developed specifically to help people with high blood pressure. Other diet plans, such as the Nordic and Mediterranean diets are also effective (2).  What these diets all have in common are plenty of fruits, vegetables and whole grains, moderate amounts of lean protein, fish and dairy, legumes, nuts and seeds, and low levels of meat, alcohol and sugary foods (3). Several changes in the composition of these heart-friendly diets compared to average diets promote heart health. For example, the high potassium, calcium and magnesium content of the diets helps to maintain a normal electrolyte balance and blood pressure (2). The consumption of dietary fiber, particularly oat beta-glucans, has been associated with improvements in blood pressure (4). Dietary component resveratrol, a bio-active dietary compound found in red wine, berries and peanuts, has been shown to modestly improve blood pressure when given as a supplement (5). This effect is likely due to the effects resveratrol has on the lining of blood vessels: resveratrol is able to increase the production of nitric oxide in blood vessel cells, which improves the ability of the blood vessels to expand and react to changes in blood pressure (6).

Pillar No. 2 – Healthy Blood Lipids

A healthy blood lipid profile is one for which total cholesterol, “bad” cholesterol and triglyceride levels are low, and “good” cholesterol levels are high. Nutrition can help modify the blood lipid profile to one that is healthy. This promotes heart health by limiting the process of atherosclerosis (plaques forming in the arteries). The monounsaturated fat content as well as polyphenol components of the essential Mediterranean diet component virgin olive oil are thought to be responsible for its positive effects on the blood lipid profile, specifically increasing levels of “good” cholesterol, and reducing “bad” cholesterol (7).

Triglycerides are considered an independent risk factor for heart attacks and cardiovascular disease. Omega-3 fatty acids have been shown to dose-dependently reduce serum triglycerides (8), thereby improving the blood lipid profile. They work by reducing production of triglycerides and increasing their turnover. Antioxidant vitamins C and E also improve the lipid profile by reducing oxidative stress from low-density lipoprotein (LDL)-cholesterol (9, 10).

The link between high fiber diets and lower cholesterol leading to reduced rates of cardiovascular disease has been known for decades (11). Dietary fiber is able to bind to bile acids produced as a normal part of digestion. These bile acids are formed from cholesterol. After binding with dietary fiber, bile acids are excreted rather than being recycled. The body is stimulated to produce more bile acids from cholesterol to replace those lost with dietary fiber, thus reducing cholesterol levels (12). A health claim establishing a cause-and-effect relationship between one particular dietary fiber, oat beta-glucan, and cholesterol reduction has been approved by the European Commission and the U.S. Food and Drug Administration (13, 14), at intakes of at least 3 grams per day.

Pillar No. 3 – Blood Flow

A healthy blood flow is important for heart health. Components in the blood – platelets – affect how the blood flows and clots. On the one hand, blood clotting is essential for the body to repair itself after injury. On the other hand, a heightened clotting ability increases risk of stroke, deep vein thrombosis and pulmonary embolisms. Due to the aging process, blood thickens and is more likely to form dangerous clots (15). Components in food can help maintain a normal blood flow. For example, tomatoes show beneficial effects on platelet function (16), and a water-soluble tomato extract was effective in reducing platelet aggregation (17), leading to an approved health claim in the EU (18).

The long-chain omega-3 fatty acids EPA and DHA have also been shown to affect platelet function (19). They are incorporated into blood cell membranes in place of long-chain omega-6 fatty acid arachidonic acid, which reduces the production of thromboxane A2, a blood clot promoter. In addition, several polyphenols, especially those from cocoa, but also in tea, red wine, berries and onion, show an anti-platelet effect (19).

References

  1. McAloon, C.J., et al., The changing face of cardiovascular disease 2000-2012: An analysis of the world health organisation global health estimates data. Int J Cardiol, 2016. 224: p. 256-264.
  2. Ndanuko, R.N., et al., Dietary Patterns and Blood Pressure in Adults: A Systematic Review and Meta-Analysis of Randomized Controlled Trials. Adv Nutr, 2016. 7(1): p. 76-89.
  3. Sacks, F.M., et al., Rationale and design of the Dietary Approaches to Stop Hypertension trial (DASH). A multicenter controlled-feeding study of dietary patterns to lower blood pressure. Ann Epidemiol, 1995. 5(2): p. 108-18.
  4. Evans, C.E., et al., Effects of dietary fibre type on blood pressure: a systematic review and meta-analysis of randomized controlled trials of healthy individuals. J Hypertens, 2015. 33(5): p. 897-911.
  5. Liu, Y., et al., Effect of resveratrol on blood pressure: a meta-analysis of randomized controlled trials. Clin Nutr, 2015. 34(1): p. 27-34.
  6. Bonnefont-Rousselot, D., Resveratrol and Cardiovascular Diseases. Nutrients, 2016. 8(5).
  7. Carluccio, M.A., et al., Vasculoprotective potential of olive oil components. Mol Nutr Food Res, 2007. 51(10): p. 1225-34.
  8. Backes, J., et al., The clinical relevance of omega-3 fatty acids in the management of hypertriglyceridemia. Lipids Health Dis, 2016. 15(1): p. 118.
  9. Wallert, M., et al., Regulatory metabolites of vitamin E and their putative relevance for atherogenesis. Redox Biol, 2014. 2: p. 495-503.
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  11. Kritchevsky, D. and J.A. Story, Fiber, hypercholesteremia, and atherosclerosis. Lipids, 1978. 13(5): p. 366-9.
  12. Kay, R.M., Effects of dietary fibre on serum lipid levels and fecal bile acid excretion. Can Med Assoc J, 1980. 123(12): p. 1213-7.
  13. EFSA, Panel on Dietetic Products, Nutrition and Allergies: Scientific Opinion on the substantiation of a health claim related to oat beta glucan and lowering blood cholesterol and reduced risk of (coronary) heart disease pursuant to Article 14 of Regulation (EC) No 1924/2006. EFSA Journal, 2010. 8(12): p. 1885-n/a.
  14. U.S. Food and Drug Administration. CFR - Code of Federal Regulations Title 21. Part 101: Food labelling. Subpart E: Specific Requirements for Health Claims. Section 101.81 Health claims: Soluble fiber from certain foods and risk of coronary heart disease (CHD). 2016; Available from: https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfCFR/CFRSearch.cfm?fr=101.81.
  15. Alexandru, N., et al., Platelet reactivity in chronic venous insufficiency. Clin Lab, 2011. 57(7-8): p. 527-34.
  16. Dutta-Roy, A.K., L. Crosbie, and M.J. Gordon, Effects of tomato extract on human platelet aggregation in vitro. Platelets, 2001. 12(4): p. 218-27.
  17. O'Kennedy, N., et al., A randomised controlled trial comparing a dietary antiplatelet, the water-soluble tomato extract Fruitflow, with 75 mg aspirin in healthy subjects. Eur J Clin Nutr, 2016.
  18. EFSA, Panel on Dietetic Products, Nutrition and Allergies: Scientific Opinion on the modification of the authorisation of a health claim related to water-soluble tomato concentrate and helps to maintain a healthy blood flow and benefits circulation pursuant to Article 13(5) of Regulation (EC) No 1924/2006 following a request in accordance with Article 19 of the Regulation (EC) No 1924/2006. EFSA Journal, 2010. 8(7): p. 1689.
  19. Bachmair, E.M., et al., Dietary manipulation of platelet function. Pharmacol Ther, 2014. 144(2): p. 97-113.