Low Fat vs. Low Carbohydrate Diet: Coronary Artery Disease. Christina Light Craigo MSN ACNP AACC Los Angeles Cardiology Associates January 27, 2018

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1 Low Fat vs. Low Carbohydrate Diet: Coronary Artery Disease Christina Light Craigo MSN ACNP AACC Los Angeles Cardiology Associates January 27, 2018

2 Diet and Cardiovascular Risk The rise in extreme obesity is significantly more prevalent among women than men Suboptimal diet remains the leading cause of poor health in the US and worldwide Yet, the definition of a healthy diet remains controversial. Current guidelines recommend a low-fat diet (<30% of energy) and limiting saturated fatty acids to less than 10% of energy intake by replacing them with unsaturated fatty acids.

3 Avoidance of CAD There is an absence of coronary artery disease in rural China, Papua Highlanders, Central Africa, Tarahumara Indians Blue Zones of Okinawa, Sardinia, Loma Linda, Icaria, and Nicoya Peninsula have some of the highest rates of longevity in the world; their diets are all predominantly plant-based. There are Blue Zone Projects in the U.S. Hermosa/Manhattan Beach Heart disease is NOT an inevitable part of the aging process.

4 Predictors of CV Risk Postprandial hypertriglyceridemia Strong predictor of MI Results in endothelial dysfunction through oxidative stress Intake of trans-fat Insulin-resistance

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9 Saturated Fat: Risk of CHD 84,628 women, 42,908 men Followed years, questionnaire q 4 years Replacing 5% of energy intake from saturated fats with equivalent energy intake was associated with a lower risk of CHD: PUFA: 25% Monounsaturated fatty acids: 15% Carbohydrates from whole grains: 9% Replacing saturated fats with carbohydrates from refined starches/added sugars was not significantly associated with reduced CHD risk Saturated Fats Compared with Unsaturated Fats and Sources of Carbohydrates in Relation to Risk of Coronary Heart Disease. A Prospective Cohort Study. Yanping Li, PhD, Adela Hruby, PhD, MPH et a. Journal of the American College of Cardiology 2015.

10 The Women s Health Initiative 48,835 women ages followed for 8.1 years Intensive behavior modification, reduced fat intake to 20% calories and increased vegetables and grains vs. control Intake of saturated fat was less than 10%, intakes of polyunsaturated fat, vegetables, fruits and fiber lower than now recommended End points: CHD, stroke, and CVD

11 Cumulative Hazards for CHD (MI, CHD Death, or Revascularization): All Participants Low-Fat Dietary Pattern and Risk of Cardiovascular DiseaseThe Women's Health Initiative Randomized Controlled Dietary Modification Trial. Barbara V. Howard, PhD; Linda Van Horn, PhD; Judith Hsia, MD; et al. JAMA. 2006;295(6):

12 Cumulative Hazards for CHD (MI, CHD Death, or Revascularization): Participants without CVD Low-Fat Dietary Pattern and Risk of Cardiovascular DiseaseThe Women's Health Initiative Randomized Controlled Dietary Modification Trial. Barbara V. Howard, PhD; Linda Van Horn, PhD; Judith Hsia, MD; et al. JAMA. 2006;295(6):

13 Meta-analysis of prospective cohort studies evaluating the association of saturated fat with cardiovascular disease. Patty W. Siri-Tarino, Qi Sun, Frank B. Hu, and Ronald M. Krauss. American J Clin Nut 2010:91: Fat Intake and Risk of CVD Trans fats is associated with an increased risk of coronary heart disease Polyunsaturated and monosaturated fats are associated with a decreased risk of CAD Data analyzing saturated fat intake is inconsistent Not all saturated fat is linked to CVD Cheese, Yogurt, Nuts Red meat and processed meats are associated with cardiovascular risk

14 Risk of Mortality Associated with Replacement of 3% Energy from Various Animal Protein Sources with Plant Protein High animal protein intake is positively associated with CV mortality, especially among individuals with 1 lifestyle risk factor High plant protein intake is associated with lower all-cause and cardiovascular mortality Association of Animal and Plant Protein Intake with All Cause and Cause Specific Mortality. Singyang Song, MD et al. JAMA Intern Med. 2016

15 Saturated vs. Unsaturated Fats Main sources of saturated fat to be decreased are: dairy fat (butter), lard (pork), beef tallow, palm oil, palm kernel oil, and coconut oil Polyunsaturated fats are contained in canola oil, corn oil, soybean oil, peanut oil, safflower oil, sunflower oil, and walnuts, avocados, and tree nuts

16 What about Coconut Oil? The main fatty acid in coconut oil is lauric acid which can be classified as either a medium chain or long chain fatty acid In terms of digestion and metabolism, it behaves more as a long-chain fatty acid because the majority of it (70-75%) is absorbed with chylomicrons Coconut oil generally raises total and LDL cholesterol to a greater extend than unsaturated plant oils, but to a lesser extent than butter HDL cholesterol is higher with coconut oil consumption, there is no sign difference in triglyceride level Review of the literature shows no evidence that coconut oil should be viewed differently from other sources of dietary saturated fat

17 Dietary Fat Restriction for Reversal of CHD Randomized controlled trial conducted from patients with mod to severe CHD randomized to intensive lifestyle or control Intensive lifestyle: 10% fat whole foods vegetarian diet, aerobic exercise, stress mgmt, smoking cessation, psychosocial support Outcome measures: adherence to intensive lifestyle changes, changes in coronary artery percent diameter stenosis and cardiac events Intensive Lifestyle Changes for Reversal of Coronary Heart Disease. Dean Ornish MD, et al. JAMA December 16, 1998.

18 Dietary Fat Restriction Lifestyle group Patients lost 23.9lbs at 1 year and 12.8lbs at 5 years LDL dec by 40% at 1 year and remained 20% below baseline at 5 years 91% reduction in reported angina after 1 year and 72% reduction after 5 years Average percent diameter stenosis as baseline had a 4.5% relative improvement and a 7.9% relative improvement after 5 years Control Group Patients weight changed little from baseline LDL dec by 1.2% at 1 year and by 19.3% at 5 years 186% increase in frequency of angina and 36% dec after 5 years Average percent diameter stenosis had a 5.4% relative worsening and a 27.7% relative worsening after 5 years

19 In Summary: Saturated vs. Unsaturated Fats High intake of polyunsaturated fatty acids and carbohydrates from whole grains are associated with a lower risk of CHD Replacing saturated fats with PUFA has been associated with a 25-30% reduction in risk Carbohydrates from refined starches/added sugars are positively associated with a risk of CHD Substitution of animal protein with plant protein has been related to a lower incidence of CVD and DM Low-fat diet has not been showed to reduce cardiovascular risk

20 High intake of carbohydrates Raises plasma fasting triglycerides primarily by enhancing hepatic synthesis of VLDL Reduces HDL Greater intake of starches with high glycemic indexes is associated with insulin resistance Why Focus on Carbs?

21 Sugars

22 Added Sugar = CV Mortality Added Sugar Intake and Cardiovascular Diseases Mortality Among US Adults. Quanhe Yang, PhD; Zefeng Zhang, MD, PhD; EdwardW. Gregg, PhD;W. Dana Flanders, MD, ScD; Robert Merritt, MA; Frank B. Hu, MD, PhD

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24 Added Sugar Intake Over 7-8% added sugar in our diets (125 calories per day) causes a 3-fold increased risk of cardiovascular mortality.

25 An Alterative View on Obesity Refined carbohydrates and added sugars Altered physiology/hormones Insulin Resistance Internal starvation Decreased exercise and increased food intake Leptin Resistance Obesity

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27 Bias or Science?

28 Systematic Review of Systematic Reviews Linking SSB s to Obesity: Reporting Bias 18 Systemic Reviews 6 had financial conflict with food/beverage industry 12 had no financial conflict 5 concluded no basis of evidence 10 concluded that SSB could be a potential risk Bes-Rastrollo et al; Plos Medicine, 201

29 Glycemic Load and CHD in Women 75, 521 women aged without DM, MI, CVD. Followed for 10 years Dietary glycemic load directly associated with increased risk of CHD Estimated relative risk for women in the highest quintile 1.57 The association between dietary glycemic load and CHD risk was most evident among women with body weights average or above average (BMI >23) A prospective study of dietary glycemic load, carbohydrates intake and risk of coronary heart disease in US women. Simin Liu, et al. Am J Clin Nutr 2000.

30 RRs of Coronary Heart Disease According to BMI and GL A prospective study of dietary glycemic load, carbohydrates intake and risk of coronary heart disease in US women. Simin Liu, et al. Am J Clin Nutr 2000.

31 Low Carbohydrate-Diet Score and the Risk of Coronary Heart Disease in Women. Thomas L. Halton, ScD. Et al. The New England Journal of Medicine. Nov 9, 2006; 355: Low Carb Diet Risk of CHD in Women 82,802 women completed questionnaire, 20 year follow up (date from Nurses Health Study) There is a direct association between glycemic load and CHD, likely because glycemic load reflects both the quantity and quality of carbohydrates When vegetables sources of fat and protein were chosen, low carb diet was associated with a moderately lower risk of coronary heart disease

32 Dietary Effect on Lipids Increased carbohydrate intake is associated with lower LDL but also: Lower HDL Higher Triglycerides Higher total cholesterol-to-hdl ratio Higher ApoB-toApoA1 ratio (strongest lipid predictor of myocardial and ischemic strokes)

33 Low-Carb Diet for Obesity A Randomized Trial of a Low-Carbohydrate Diet for Obesity Gary D. Foster, PhD; Holly R. Wyatt; et al. N ENGL J MED 348;21.

34 In Summary: Low-Carbohydrate Diets Low-carb diets consistently increase HDL cholesterol Low saturated fat diets decrease LDL cholesterol levels Low carbohydrates diets have typically been more effective for short-term reduction of serum triglycerides, glucose and/or insulin. Low carbohydrate/high protein diets used without consideration of the nature of carbohydrates or sources of protein are associated with increased risk of CVD The degree to which a patient exhibits features of metabolic syndrome might guide the degree of carbohydrates restriction to recommend

35 Low Carb vs Low Fat Effect on Risk Factors for CVD 148 obese men and women without CVD/DM randomized to a low carb (<40gm/day) or low fat (<30%). 88% female participants, 51% black. Followed for 12 months Low carb diet had greater increases in HDL No significant change in total cholesterol or LDL Low carb diet had greater decreases in: Weight, Fat mass, Ratio of total/ HDL cholesterol, Triglyceride level No sign difference in BP or serum BG Effects of Low-Carbohydrate and Low-Fat Diets. A randomized Trial. Lydia Bazzano et. al. Annals of Internal Medicine. 2014

36 Low carb group had significant decreases in estimated 10-year risk for CHD at 6 and 12 months compared with the low fat diet

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39 Lyon Heart Study 605 participants <70yo with MI within 6 months Mediterranean vs. AHA Step 1 Canola oil based margarine supplied to Mediterranean grp Trial discontinue prematurely at 27 months Followed for 46 months 72% reduction in CV death and recurrent MI

40 The PREDIMED Trial 7447 persons, 57% women who were at high cardiovascular risk but without disease Randomized to: Mediterranean diet supplemented with extravirgin olive oil Mediterranean diet supplemented with mixed nuts Control (low fat) diet Primary end point: major cardiovascular events

41 The PREDIMED Trial Estruch, R., et al. NEJM. 2013; 368:

42 Diabetes Free Survival: Mediterranean Diet vs. Control Estruch, R., et al. NEJM. 2013; 368:

43 Frequency of Nut Consumption and Mortality Risk Guasch-Ferré, M., et al. BMC Medicine, 2013; 11:164.

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45 AHA/ACC Diet Recommendations Consume a dietary pattern that emphasizes intake of vegetables, fruits, and whole grains; includes low-fat dairy products, poultry, fish, legumes, non-tropical vegetable oils and nuts; and limits intake of sweets, sugar-sweetened beverages and red meats. Aim for a dietary plan to achieve 5%-6% of calories from saturated fats Reduce intake of calories from saturated and trans fat intake Follow the DASH dietary pattern and the Mediterranean diet, Class I Rec LOE A

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48 Prevalence of Obesity in Los Angeles WIC 4 Year Old Children

49 Economic Disparity in Childhood Obesity

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51 Identify patients who need to lose weight (BMI and waist circumference) Counsel overweight/obese patients about lifestyle change and their clinical benefits Prescribe a diet to achieve reduced calorie intake Comprehensive lifestyle intervention Bariatric surgical treatment for obesity (adults with a BMI 40 who have not responded to behavioral treatment with or without pharmacotherapy)

52 Low Carbohydrate vs. Low Fat Diet A randomized trial comparing a very low carbohydrate diet and a calorie restricted low fat diet on body weight and cardiovascular risk factors in healthy women. Bonnie J. Brehm et al.

53 Weight Loss with a Low-Carbohydrate, Mediterranean or Low-Fat Diet 2 year trial 322 moderately obese subjects randomly assigned to: low fat, restricted calorie; Mediterranean, restricted calorie; or low carbohydrates, non-restricted-calorie Mean weight loss were: Low Fat: 3.3kg Mediterranean: 4.6kg Low Carbohydrates: 5.5kg Weight loss with a low carb, Mediterranean or low fat diet. Iris Shai et al. The New England Journal of Medicine. July 17, 2008.

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56 Comparison of the Atkins, Zone, Ornish, and LEARN Diets for Change in Weight and Related Risk Factors Among Overweight Premenopausal Women. The A to Z weight loss study: A randomized Trial. Christopher Gardner, et al. JAMA March Vol 297, No. 9 Comparison of Diets for Change in Weight and Related Risk Factors Among Overweight Women 311 overweight/obese women followed for 12 months Randomly assigned to Atkins, Zone, Ornish and LEARN Weight loss was greater for women in the Atkins diet group at 12 months Inc HDL and reduction in triglycerides favored the Atkins group Changes in LDL at 2 months favored the LEARN and Ornish diets over the Atkins, not significant at 6 and 12 months

57 Weight Change Relative to Baseline Comparison of the Atkins, Zone, Ornish, and LEARN Diets for Change in Weight and Related Risk Factors Among Overweight Premenopausal Women. The A to Z weight loss study: A randomized Trial. Christopher Gardner, et al. JAMA March Vol 297, No. 9

58 What is the Superior Dietary Approach? The amount of weight loss was associated with self-reported dietary adherence level For each diet, decreasing levels of total/hdl cholesterol, C-reactive protein and insulin were significantly associated with weight loss with no significant difference in diets Overall dietary adherence rates were low, between 50-65% There was a higher discontinuation rate for the Atkins and Ornish diet groups

59 Dietary Adherence One-Year Changes in Body Weight as a Function of Diet Group and Dietary Adherence Level for All Study Participants

60 Conclusions PUFAs such as those from vegetable oils, nuts and seeds should have an expanded role as a replacement for SFAs. There is a direct association between glycemic load and CHD Sustained adherence to a diet rather than diet type is the key predictor of weight loss and cardiac risk factor reduction The Mediterranean diet has the highest adherence rate and proven reduction in CVD.

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