A Fresh Perspective. Lean Beef and Heart Health: ... Fresh red meat is not associated with CHD risk

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1 Spring Fresh red meat is not associated with CHD risk R Lean Beef and Heart Health: A Fresh Perspective esearchers from the Harvard School of Public Health recently concluded that consuming 100 g per day of fresh red meat is not linked to the development of CHD or type 2 diabetes. 1 This finding is the result of the largest systematic review and meta-analysis of the worldwide evidence to examine how eating fresh red meat such as beef, pork and lamb and processed meat (i.e., hot dogs, bacon, salami, sausages, luncheon meats) relates to the risk of CHD and type 2 diabetes. The finding that fresh red meat is not associated with CHD calls into question results from previous studies that grouped fresh and processed meats together. The British Nutrition Foundation concludes red meat makes a positive contribution to health A recent review published by the British Nutrition Foundation concluded that the relationship between red meat and health is a positive one. 2 A moderate intake of lean red meat makes a significant positive contribution to both micronutrient and macronutrient intakes without negative health effects. NEW RESEARCH: Harvard review finds fresh red meat intake of 100 g per day is not associated with coronary heart disease (CHD) risk. Lean red and white meats have equal effects on blood cholesterol. Canadian red meat intakes are moderate, in line with Canada s Food Guide and similar to those of Mediterranean countries. BOTTOM LINE: Messages to limit fresh red meat are not an effective way to reduce CHD risk and distract from other, more effective strategies to improve overall diet quality. Brought to you by the Registered Dietitians at Canada Beef Note: The term fresh in this newsletter refers to unprocessed, single-ingredient meat (i.e., roasts, steaks, chops, stewing, ground, etc.), and it may be fresh or frozen. Red meat includes beef, pork, veal and lamb.

2 Causal evidence for meat and CHD outcomes is weak In another recent systematic review, Canadian researchers categorized the causal evidence for various dietary exposures and their associations with primary and secondary CHD outcomes as strong, modest or weak. 3 The analysis pooled prospective cohort data on a variety of dietary variables and CHD outcomes for 236,414 individuals and concluded the evidence for meat and CHD is weak. A recent prospective cohort study of 40,653 individuals in Australia also found no association between meat intakes and cardiovascular mortality. 4 Giving patients permission to choose lean red and white meats may improve their acceptance and long-term dietary adherence. 6 Lean red meat and white meat have equal effects on blood cholesterol Eight randomized controlled trials (RCTs) have demonstrated lean red meat, such as beef, is as effective as lean white meat (poultry and fish) as part of healthy diets for managing blood cholesterol levels The most recent, Beef in an Optimal Lean Diet (BOLD), led by distinguished researcher Penny Kris-Etherton, found that heart healthy diets that include lean beef as the primary protein are as effective in lowering total and LDL cholesterol as the DASH diet that emphasizes white meat and plant protein. 5 Participants following the BOLD and BOLD+diets (113 g and 153 g beef/day, respectively) experienced a 10% decrease in LDL cholesterol. These reductions were of the same magnitude as those observed with the DASH diet, recognized as a gold standard for heart health. Canadian red meat intake is moderate On average, Canadian women eat less than one serving of red meat (fresh and processed) a day (55 g), and men eat about 1 ¼3 servings a day (101 g). 13 In fact, average Canadian red meat intakes are moderate, similar to average intakes in Mediterranean countries such as Greece, Spain and Italy, and in some cases they are lower. 2 CANADIAN RED MEAT INTAKE IS WITHIN CANADA S FOOD GUIDE RECOMMENDATIONS Female Adults Male Adults Mean Intake Number of Mean Intake Number of (g/day) Food Guide (g/day) Food Guide Meat Category Servings Servings Fresh red meat 40 < Processed red meat 15 < ¼ 28 < ½ Total red meat 55 < ¼3 Source: Canadian Community Health Survey, Cycle 2.2 Nutrition, RED MEAT INTAKE IN CANADA IS SIMILAR TO MEDITERRANEAN COUNTRIES Total Red Meat Intakes Total Red Meat Intakes for Women for Men Countries (g/day) (g/day) Canada Spain Italy Greece Note: Intakes in this chart include fresh and processed red meat. Source: Wyness L et al. Red Meat in the Diet: An Update. British Nutrition Foundation Nutrition Bulletin March 2011; 36:34 77.

3 Red meat contributes little fat to Canadian diets Fresh red meat contributes only 8% of total fat and 9.5% of saturated fat on average for adults. 14 On average, a Food Guide serving of beef (75 g, cooked, trimmed of visible fat) has just 170 calories, 6.3 g total fat and 2.6 g saturated fat. 15 Other Sources Fresh Red Meat 9.5% Contribution of fresh red meat to saturated fat in Canadian diet 14 Two-thirds of the fat in lean beef does not raise LDL cholesterol About half (49%) is monounsaturated fat, mostly oleic acid, the same fat found in olive oil. About a third (30%) of the saturated fat is stearic acid, which does not raise LDL cholesterol. 18,19 The other main saturated fat in beef, palmitic acid, increases HDL as well as LDL cholesterol, therefore having little effect on the ratio of total to HDL cholesterol. 20 Source for data in pie chart: Health Canada. Canadian Nutrient File, Canadians keep it lean 71% buy lean or extra-lean ground beef. 16 Almost 80% trim visible fat from beef before and/or after cooking. 17 Monounsaturated 49% Natural Trans 3% Polyunsaturated 5% Stearic Acid 13% About 2/3 of the fat in beef is in a form that does not raise blood cholesterol Other Saturated Fats 6% Palmitic Acid 24% Beef eye of round (trimmed of visible fat) Beef sirloin steak (trimmed of visible fat) Chicken light meat (without skin) COMPARE THE FAT IN BEEF AND CHICKEN Chicken dark meat (without skin) Total Fat (g) Per 75 g Food Guide Serving cooked, lean only. Saturated Fat Unsaturated Fat Source: Health Canada, Canadian Nutrient File, (Values for beef eye of round steak, beef top sirloin steak, chicken broiler light meat, and chicken broiler dark meat.)

4 Moderately higher protein intakes may improve heart health Recent evidence suggests the Recommended Dietary Allowance for adult protein intakes, 0.8 g/kg/day, 21 significantly underestimates requirements by as much as 50%. 22 With average intakes of less than 17% of energy from protein, 23 many Canadians have protein intakes at the lower end of the current Acceptable Macronutrient Distribution Range of 10% to 35% of energy from protein. 21 Higher protein intakes, within the recommended range, may help increase satiety, reduce hunger and lower energy intakes. 24,25 RCTs have demonstrated that replacing some carbohydrates with protein may improve a number of cardiovascular risk factors, for example by lowering blood pressure 26 and improving glycemic control and blood triglyceride levels. 27,28 Time for a new approach The traditional nutrient-focused guidance is often confusing and distracts from more effective messages aimed at today s overfed, undernourished population. Calories consumed from Other Foods such as soft drinks, chocolate bars, potato chips, and added fats and sugars are second only to calories from grain products. PRACTICE POINTS Clients can benefit from advice to: Make most of their meat choices fresh (i.e., unprocessed). Choose both lean red and white meats. Consume moderately higher protein intakes. If overall dietary patterns are more important than single dietary components 29, it makes sense for our dietary guidance to focus on food, not nutrients. Clients can benefit from advice on how to enjoy whole, minimally processed foods more often. This results in diets naturally lower in salt, trans fat, saturated fat, added sugar and refined carbohydrates and higher in fibre, unsaturated fats, minerals, antioxidants and phytochemicals. 30 This type of positive guidance can also lead to diets that are naturally more satiating and lower in energy. 31 In summary: Fresh red meat intakes are moderate and contribute only 8% of total and 9.5% of saturated fat on average for adults. Higher protein intakes may benefit heart health. Advising patients to avoid or limit fresh red meat is unnecessarily restrictive and is not an effective strategy to lower CHD risks.

5 References Micha R, Wallace SK, Mozaffarian D. Red and processed meat consumption and risk of incident coronary heart disease, stroke, and diabetes mellitus: a systematic review and meta-analysis. Circulation 2010; 121(21): Wyness L et al. Red Meat in the Diet: An Update. British Nutrition Foundation Nutrition Bulletin March 2011; 36: Mente A et al. A Systematic Review of the Evidence Supporting a Causal Link Between Dietary Factors and Coronary Heart Disease. Arch Intern Med 2009; 169(7): Harriss LR et al. Dietary patterns and cardiovascular mortality in the Melbourne Collaborative Cohort Study. Am J Clin Nutr 2007; 86: Roussell MA et al. Beef in an Optimal Lean Diet Study: effects on lipids, lipoproteins, and apolipoproteins. Am J Clin Nutr 2012; 95(1): Davidson MH et al. Comparison of the effects of lean red meat vs lean white meat on serum lipid levels among free-living persons with hypercholesterolemia. Arch Intern Med 1999; 155: Beauchesne-Rondeau E et al. Plasma lipids and lipoproteins in hypercholesterolemic men fed a lipid-lowering diet containing lean beef, lean fish, or poultry. Am J Clin Nutr 2003; 77(3): Melanson K et al. Weight loss and total lipid profile changes in overweight women consuming beef or chicken as the primary protein source. Nutrition 2003; 19(5): Scott L et al. Effects of beef and chicken consumption on plasma lipid levels in hypercholesterolemic men. Arch Intern Med 1994; 154: Scott L et al. Effects of a lean beef diet and of a chicken and fish diet on lipoprotein profiles. Nutr Metab Cardiovasc Dis 1991; 1: Gascon A et al. Plasma lipoprotein profile and lipolytic activities in response to the substitution of lean white fish for other animal protein sources in premenopausal women. Am J Clin Nutr 1996; 63(3): Jacques H et al. Effects on plasma lipoproteins and endogenous sex hormones of substituting lean white fish for other animalprotein sources in diets of postmenopausal women. Am J Clin Nutr 1992; 55: Garriguet D. Overview of Canadians Eating Habits Nutrition: Findings from the Canadian Community Health Survey. Statistics Canada, 2006, Catalogue no MIE No. 2. Available at: (Accessed April 13, 2011.) 14. Calculations based on data from Statistics Canada, Canadian Community Health Survey 2.2, Nutrition, 2004, and Health Canada, Canadian Nutrient File, Health Canada. Based on Canadian Nutrient File, 2010 average for steaks (#6174) and roasts (#6168). 16. Nielsen Market Track, July Beef Information Centre. Consumer Beef Trimming Practices 2010, Kris-Etherton PM and Yu S. Individual fatty acid effects on plasma lipids and lipoproteins: human studies. Am J Clin Nutr 1997; 65(Suppl):1628S 44S. 19. Yu S et al. Plasma cholesterol-predictive equations demonstrate that stearic acid is neutral and monounsaturated fatty acids are hypocholesterolemic. Am J Clin Nutr 1995; 61(5): Mensink RP et al. Effects of dietary fatty acids and carbohydrates on the ratio of serum total to HDL cholesterol and on serum lipids and apolipoproteins: a meta-analysis of 60 controlled trials. Am J Clin Nutr 2003; 77(5): Institute of Medicine. Dietary Reference Intakes for Energy, Carbohydrate, Fiber, Fat, Fatty Acids, Cholesterol, Protein, and Amino Acids. Washington DC, 2005: National Academy Press. 22. Elango R et al. Evidence that protein requirements have been significantly underestimated. Curr Opin Clin Nutr Metab Care 2010; 13(1): Statistics Canada, Canadian Community Health Survey 2.2, Austin GL et al. Trends in carbohydrate, fat, and protein intakes and association with energy intake in normal-weight, over weight, and obese individuals: Am J Clin Nutr 2011; 93(4): Weigle DS et al. A high-protein diet induces sustained reductions in appetite, ad libitum caloric intake, and body weight de spite compensatory changes in diurnal plasma leptin and ghrelin concentrations. Am J Clin Nutr 2005; 82: Hodgson JM et al. Partial substitution of carbohydrate intake with protein intake from lean red meat lowers blood pressure in hypertensive persons. Am J Clin Nutr 2006; 83(4): Nuttall et al. Effect of the LoBAG30 diet on blood glucose control in people with type 2 diabetes. Br J Nutr 2008; 99: Layman et al. Protein in optimal health: heart disease and type 2 diabetes. Am J Clin Nutr 2008; 87(Suppl):1571 5S. 29. Zelman K. The Great Fat Debate: A Closer Look at the Controversy Questioning the Validity of Age-Old Dietary Guidance. JADA 2011; 111(5): Mozaffarian D, Ludwig DS. Dietary guidelines in the 21st century a time for food. JAMA 2010; 304(6): Miller GD et al. It is time for a positive approach to dietary guidance using nutrient density as a basic principle. J Nutr 2009; 139(6):