How Low in Carbs? Outline. Case Presentation CASE. Christopher Gardner, PhD. Identifying Patient with Insulin Resistance

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1 How Low in Carbs? Christopher Gardner, PhD Stanford Prevention Research Center Stanford University, Department of Medicine Case Presentation Outline Identifying Patient with Insulin Resistance How Low in Carbs? Complexities of Low Carb Nutritionally Adequate? How? (i.e., how to lower carb intake) Sweetened Beverages, Added Sugars Non-nutritive (artificial) sweeteners Grains: Whole grain vs. flour-based products Vegetables!! Fat and Protein: Fish, Nuts and Seeds, Salad Dressing CASE 45 y/o woman whose older overweight brother just had quadruple bypass is trying to come to grips with 50 lbs of weight she has put on since getting married 20 years ago and having kids. Has been trying to lose weight on low-fat diet, unsuccessfully. Desperate for advice PMH: none Medications: none Social Hx: non-smoker, moderate alcohol intake, poor diet, sedentary lifestyle Family Hx: father has T2D, brother as described above Exam: BP-142/86 BMI-32 WC-44 Central obesity otherwise unremarkable Fasting Labs: Total-C 199 mg/dl Glucose 109 mg/dl TG 227 mg/dl AST 34 U/L HDL-C 34 mg/dl ALT 50 U/L LDL-C 120 mg/dl

2 Case Presentation Outline Identifying Patient with Insulin Resistance How Low in Carbs? Complexities of Low Carb Nutritionally Adequate? How? (i.e., how to lower carb intake) Sweetened Beverages, Added Sugars Non-nutritive (artificial) sweeteners Grains: Whole grain vs. flour-based products Vegetables!! Fat and Protein: Fish, Nuts and Seeds, Salad Dressing Am J Cardiol 2005;96: National laboratory standardization program for lipids No such lab standardization for insulin More likely to be insulin resistant if TG / HDL-C ratio is >3.5 Am J Cardiol 2005;96:

3 Identifying Patient with Insulin Resistance Take Home Point(s) TG / HDL-C >3.5 (lab values nationally standardized, unlike insulin) Non-fasting would be better OGTT (but what cut point?) Case Presentation Outline Identifying Patient with Insulin Resistance How Low in Carbs? Complexities of Low Carb Nutritionally Adequate? How? (i.e., how to lower carb intake) Sweetened Beverages, Added Sugars Non-nutritive (artificial) sweeteners Grains: Whole grain vs. flour-based products Vegetables!! Fat and Protein: Fish, Nuts and Seeds, Salad Dressing 40%? 30%? 20%?

4 Clinical Guidelines on the Identification, Evaluation, and Treatment of Overweight and Obesity in Adults The Evidence Report. National Institutes of Health. Obes Res 1998;6(Suppl)2:51S-209S. Carb ~15% Fat Protein >55% <30% 55% energy from carbohydrate 30% energy from fat and approximately 15% energy from protein ~15% <30% Carb Fat Protein >55% NIH Guidelines Obes Res 1998;6 (Suppl)2:51S-209S. Low-Carb 10%?? 20%?? 30%?? 40%?? A TO Z Baseline Diet 19% 35% 46% Gardner, JAMA 2007;297: Lower than National Guidelines? Lower than Current Diet? Induction Phase: 20 g carb/day (1,500 Kcal /day reported in A TO Z study) 5% Carbohydrate Ongoing Weight Loss Phase: 60 g carb/day (1,500 Kcal /day reported in A TO Z study) ~15% Carbohydrate

5 Protein 30% 40% Carb 30% Fat Clinical Effects of Inadequate Intake (DRI 2002 Nat l Academy of Sciences) The lower limit of dietary carbohydrate compatible with life apparently is zero, provided that adequate amounts of protein and fat are consumed. However, the amount of dietary carbohydrate that provides for optimal health in humans is unknown. There are traditional populations who ingested a high-fat, highprotein diet containing only a minimal amount of carbohydrate for extended periods of time (Masai) and in some cases for a lifetime after infancy (Alaska and Greenland Natives, Innuits, and Pampas indigenous people). There was no apparent effect on health or longevity. (Section 6, page 9) Anecdotally From small pilot study (unpublished) 15 overweight adults Given menus and shopping guides Asked to start at 10% and follow as long as possible Then allowed to move to 20%, and then 30%, and then 40% carb, as needed Diet assessed by 3-day food records (self-report) 10% Carb - VERY DIFFICULT 20% maintained by 1/2 participants for many months 40% easy

6 <40% How Low is Low Carb? Take Home Point(s) <20% is not realistic 20%-39%?? Case Presentation Outline Identifying Patient with Insulin Resistance How Low in Carbs? Complexities of Low Carb Nutritionally Adequate? How? (i.e., how to lower carb intake) Sweetened Beverages, Added Sugars Non-nutritive (artificial) sweeteners Grains: Whole grain vs. flour-based products Vegetables!! Fat and Protein: Fish, Nuts and Seeds, Salad Dressing Carbohydrates Polysaccharides Disaccharides Fiber Low Glycemic High Glycemic Sucrose (Table Sugar) Lactose Glucose Fructose Galactose Feces Corn syrup = 100% glucose High fructose corn syrup = 55% fructose, 45% glucose

7 Low fat yogurt Plain Raspberry Cultured certified organic low fat pasteurized milk Pectin Cultures Cultured certified organic low fat pasteurized milk Organic evaporated cane juice Organic raspberries Pectin Natural flavors Elderberry juice concentrate (for color) Locust bean gum Cultures 50% Carb 70% Carb Calories 90 Fat Cal. 25 % Daily Values Total Fat 2.5 g 4% Sat Fat 1.5 g 8% Cholest. 10 mg 4% Sodium 110 mg 4% Total Carb. 11 g 4% Dietary Fiber 0 g 0% Sugars 11 g Protein 7 g 15% Calories 130 Fat Cal. 20 % Daily Values Total Fat 2.0 g 3% Sat Fat 1.5 g 7% Cholest. 10 mg 3% Sodium 95 mg 4% Total Carb. 23 g 8% Dietary Fiber 0 g 0% Sugars 22 g Protein 6 g 12%

8 Atkins Zone LEARN 8 weeks 17% 28% 55% 24% 42% 34% 20% 50% 30% NOTE: The diet of those assigned to Atkins wasn t just low carb, it was also high protein and high fat Carb Fat Protein Ornish 16% 21% 63% Gardner, JAMA 2007;297: Sacks et al, NEJM 2009;360(9): Protein Carb Fat Protein 24- month Target: 15 vs. 25% (Range 10%) Actual: 20 21% (Range 1%) % energy /20/15 55/20/25 45/40/15 35/40/25 Complexities of Low Carb Take Home Point(s) Quality is also an issue (Overall food & beverage context important) Low(er) Carb is also High(er) Protein, and/or High(er) Fat (of the two, more likely to be higher FAT)

9 Case Presentation Outline Identifying Patient with Insulin Resistance How Low in Carbs? Complexities of Low Carb Nutritionally Adequate? How? (i.e., how to lower carb intake) Sweetened Beverages, Added Sugars Non-nutritive (artificial) sweeteners Grains: Whole grain vs. flour-based products Vegetables!! Fat and Protein: Fish, Nuts and Seeds, Salad Dressing Vitamin A Vitamin D Atkins Zone LEARN Vitamin E * ** * Vitamin K ** * Thiamin *** 53% ** Folic acid 48% *** Vitamin B12 * Vitamin C Calcium ** ** ** Iron *** Magnesium *** ** Zinc Intake Worsened Intake Improved Intake Worsened Key: Intake Improved * Intake Worsened Percent of Diet Group Intake Worsened Intake Improved Intake Improved *** Ornish Intake Worsened Intake Improved Fat Soluble Vitamins Water Soluble Vitamins Minerals Gardner, Am J Clin Nutr, 2010; 92:304-12

10 Nutritional Adequacy Take Home Point(s) Diets that involve extreme restrictions of major food groups or classes of macronutrients (e.g., very low carb, very low fat) are likely to be low in SOME essential nutrients. This can be compounded by lowering total energy intake. Avoid extremes. A low carb diet based on choosing healthy sources of carbs and fats can be nutritionally adequate. Case Presentation Outline Identifying Patient with Insulin Resistance How Low in Carbs? Complexities of Low Carb Nutritionally Adequate? How? (i.e., how to lower carb intake) Sweetened Beverages, Added Sugars Non-nutritive (artificial) sweeteners Grains: Whole grain vs. flour-based products Vegetables!! Fat and Protein: Fish, Nuts and Seeds, Salad Dressing

11 Between the 70 s and the end of the century, caloric intake in men and women in the U.S. is estimated to have increased by ~ Kcal/day. The increase is explained primarily by increased carbohydrate intake. Calories Men Year Total Carb Fat 3000 Women Year Sweetened Beverage Trends Kcal / Day from Sugar- Sweetened Drinks in the U.S Nielsen & Popkin Am J Prev Med, 2004;27: Americans consume more calories/day today than several decades ago. Nearly ½ this increase is accounted for by consumption of sweetened beverages Brownell & Frieden NEJM 2009;360: Compensation Meta-Analysis (de la Hunty, Nutrition Bulletin, 2006;31: ) Four RCT s with beverages: Sugared vs. Aspartame Subsequent 24-hour intake monitored Compensation for the calories from the caloric beverages = 15% PRACTICAL INTERPRETATION: Adding a soda Given a meal plus non-caloric beverage (e.g., sweetened with aspartame) switching to 240 calories from 20 oz soda results in low/poor compensating - consuming 36 fewer calories less in the next 24 hours, or a net INCREASE in calories consumed of ~200 Kcal. Replacing a soda with water or non-caloric beverage Given a meal plus a 20 oz soda, switching to water (or non-caloric beverage), over the next 24 hours 36 of the 240 calories will be added to daily intake, for a net DECREASE in calories consumed of ~200 Kcal.

12 Sweetened Beverages Take Home Point(s) Evidence suggests compensation for energy intake from sweetened beverages is incomplete. Potentially important part of problem, makes them an important potential solution Case Presentation Outline Identifying Patient with Insulin Resistance How Low in Carbs? Complexities of Low Carb Nutritionally Adequate? How? (i.e., how to lower carb intake) Sweetened Beverages, Added Sugars Non-nutritive (artificial) sweeteners Grains: Whole grain vs. flour-based products Vegetables!! Fat and Protein: Fish, Nuts and Seeds, Salad Dressing

13 the American Heart Association recommends reductions in the intake of added sugars. AHA Scientific Statement (under Review) Non Nutritive Sweeteners: Current Use and Health Perspectives A Scientific Statement from the American Heart Association Christopher D. Gardner, PhD, Chair; Judith Wylie-Rosett, EdD, RD; Alice Lichtenstein, DSc, FAHA; Rachel K. Johnson, PhD, MPH, RD; Samuel S. Gidding, MD; Lyn M. Stephen, PhD, MPH, RD, FAHA; Diane Reader RD, CDE on behalf of the American Heart Association Nutrition Committee of the Council on Nutrition, Physical Activity and Metabolism, and the American Diabetes Association OBJECTIVE: Address the potential role of nonnutritive sweeteners in helping Americans adhere to the recommendation to reduce the intake of added sugars in the context of current usage and health perspectives. Artificial (non-nutritive) sweeteners Aspartame 600X sweeter than sucrose X sweeter than sucrose X sweeter than sucrose

14 Artificial (non-nutritive) sweeteners Acesulfame K 200X sweeter than sucrose 7,000-13,000X sweeter than sucrose 200X sweeter than sucrose Artificial (non-nutritive) sweeteners Take Home Point(s) Could contribute to weight loss / control.if used to replace current similar products with added sugars (e.g., diet sodas, coffee/tea) accompanied by incomplete compensation Could be ineffective, and even counter productive, IF accompanied by full or >full compensation perpetuates preference for sweet taste strategy leads to choosing more packaged/processed foods with low satiety and high energy density Case Presentation Outline Identifying Patient with Insulin Resistance How Low in Carbs? Complexities of Low Carb Nutritionally Adequate? How? (i.e., how to lower carb intake) Sweetened Beverages, Added Sugars Non-nutritive (artificial) sweeteners Grains: Whole grain vs. flour-based products Vegetables!! Fat and Protein: Fish, Nuts and Seeds, Salad Dressing

15 White flour Whole wheat flour Glycemic Index Whole grain = White When whole grains are pulverized to make flour, the surface area of the grain product is dramatically increased, leading to rapid digestion and appearance of blood glucose virtually the same as bread made from white flour. Table A1. Glycemic index (GI) and glycemic load (GL) values determined in subjects with normal glucose tolerance: 2008 Food number & item GI Glucose GI Bread Subjects Type & Number Reference Food & Time Period Ref. Serving Size (g) Avail. Carbohydrate Glycemic (g/serv) Load 1. Banana Cake.. 47 ± 8 67 Normal, 8 Bread, 2h Wonder white bread 72 ± Normal, 10 Glucose, 2h UO Whole wheat bread 75 ± Normal, 8 Glucose, 2h Ice Cream, Vanilla 38 ± 3 54 Normal, 10 Glucose, 2h UO Chickpeas 36 ± 5 51 Normal, 6 Glucose, 2h Sucrose 65 ± 9 93 Normal, 7 Glucose, 2h Carrots, raw, diced 35 ± 5 50 Normal, 7 Glucose, 2h Carrots, peeled, diced, boiled 49 ± 2 70 Normal, 7 Glucose, 2h International tables of glycemic index and glycemic load values: Atkinson et al., Diabetes Care Dec;31(12):2281-3: On line Appendices (2,480 food items)

16 Wheat Berries GI = ~40 GI = ~100 White wheat flour bread GI = ~100 Whole wheat flour bread INGREDIENTS 100% wholegrain Irish oats Total Carbs (g): 26 Fiber (g): 4 Sugar (g): 0 (For 1/4 cup dry, 150 calories) CP

17 Grains: White flour vs. Whole wheat flour Take Home Point(s) White flour products high in carbs and glycemic index, low nutrients (Cut these out first) Whole wheat flour products high in carbs and glycemic index, higher in nutrients than non-whole wheat (Next to go, a close second) Whole grains high in carbs, low in glycemic index, high in nutrients (Last to go) Case Presentation Outline Identifying Patient with Insulin Resistance How Low in Carbs? Complexities of Low Carb Nutritionally Adequate? How? (i.e., how to lower carb intake) Sweetened Beverages, Added Sugars Non-nutritive (artificial) sweeteners Grains: Whole grain vs. flour-based products Vegetables!! Fat and Protein: Fish, Nuts and Seeds, Salad Dressing Carbohydrates Amount Calories Carbs (g) Protein (g) Fat (g) Sat. Fat (g) Fiber ~1/2 cup ~125 ~26 ~3 ~1 <1 ~2 g ~1 slice ~125 ~20 ~5 ~2 <1 ~4 g ~4 ~125 ~28 ~4 <1 <1 ~8 g ~2-1/2c ~125 ~20 ~10 <1 <1 ~8 g ~1/2 cup ~125 ~7.5 ~12 ~7 ~1 ~4 g

18 Vegetables!! Take Home Point(s) Plenty of room for these Proportionally high in carbohydrates But large quantities need to be consumed to get a high total carbohydrate intake from vegetables alone What you eat WITH your vegetables is equally important Case Presentation Outline Identifying Patient with Insulin Resistance How Low in Carbs? Complexities of Low Carb Nutritionally Adequate? How? (i.e., how to lower carb intake) Sweetened Beverages, Added Sugars Non-nutritive (artificial) sweeteners Grains: Whole grain vs. flour-based products Vegetables!! Fat and Protein: Fish, Nuts and Seeds, Salad Dressing Variety of veggies Low Carb Salad Add: Nuts Seeds Avocados Edamame or tofu Oil-based dressing ADD: Strips of fish, chicken, beef

19 SALMON: High in omega-3 fats and protein TUNA: High in omega-3 fats and protein Coconut Curry Vegetables

20 Vegetable Omelet Whipped Cream on Ice Cream Butter on Grilled Steak Overall Summary Identifying Insulin Resistance with simple clinical marker(s) TG / HDL-C ratio > 3.5 How Low is Low Carb? 20-39% of calories Carbs are Complex / Complicated Nutritional quality of carbs (and foods rich in carbs) highly variable High nutritional quality can be achieved on low carb diets Strategies for Lowering Carbs, Lowering Energy Intake, Maintaining Nutritional Quality 1.Decrease / limit / avoid sweetened beverages 2.Decrease / limit / avoid added sugars in general 5.Decrease / limit / avoid wheat flour based foods (bread, bagels, breakfast cereals) 6.Eat plenty of vegetables 7.Add nutrient dense sources of fats and proteins (e.g., fish, nuts, seeds, avocados, oil-based salad dressings, small servings of poultry and meat)