3/22/2013 Debunking Nutrition Myths Marie Spano, MS, RD, CSCS, CSSD Twitter: @mariespano Nutrition Observations 1. We/media boil down nutrition into “sound bites” that don’t always accurately convey the message nor are they applicable for the masses 1. There’s more to nutrition than calories & macronutrients. Help your clients understand how what they are eating affects their bodies and thus their ability to train. Top Nutrition Myths 1. 2. 3. 4. 5. 6. Detox Diets Work Gluten Makes You Fat and Tired Soy De‐Masculinizes a Man We Don’t Need Dairy for Calcium Artificial Sweeteners are Poison We Can Get all of Our Nutrients from Food 1 3/22/2013 We are exposed to environmental toxins, pesticides, allergens, waste & inflammatory substances through foods on a daily basis. These build up in our bodies and make us sick, fat and tired. Detox Diets Detox Diets and Cleanses Supposedly: • Get rid of harmful toxins • Cleanse organs • Help you lose weight • Give you Energy • Decrease inflammation • Decrease disease risk Typical Detox/Cleanse Rules • NO: – Alcohol – Caffeine – Highly processed and refined foods – Foods grown with herbicides/pesticides – Simple sugars • Yes: – Regimented supplements/detox drinks – (maple syrup, lemon juice, diuretics, laxatives) 2 3/22/2013 Specific Cleanses • • • • Master Cleanse Raw Food Diet BluePrint Cleanse Colon Cleanse Detox Diets/Cleanses • The Good: – Cuts out low quality food – Cuts excess calories – Might eliminate some food sensitivities – Raw Food Diet: • Possibly fewer carcinogenic compounds consumed • Fewer nutrients lost in processing Heterocyclic amines, polycyclic aromatic hydrocarbons 3 3/22/2013 Pick 2: What do these two have in common? • Acrylamides – – – – High temperature Frying, roasting, baking Sugars + an amino acid Mainly plant foods – Produced on purpose for: • Grouts, water treatment products, plastics, cosmetics – Cancer in animals at very high doses – Nerve damage in people exposed to high levels at work 4 3/22/2013 Raw Food Diet Research Summary • Cross sectional study: – Over 200 raw foodies of at least 2 years with > 70% diet raw food – 1500 – 1800 grams raw food daily – 38% B12 deficient – None had high triglycerides – 46% low serum HDL J Nutr. 2005 Oct;135(10):2372‐8 Raw Food Diet Research Cross sectional study, 216 men, 297 women Examining body weight and amenorrhea Average 3.7 years on the diet Divided into 5 groups based on amount of raw food in their diet: 70‐79%, 80‐89%, 90‐94%, 95‐99%, 100% • BMI below normal: • • • • – 14.7% of males – 25% of females • 30% of women < 45 yr. old had oligomenorrhea or amenorrhea Ann Nutr Metab. 1999;43(2):69‐79. Detox Diets/Cleanses • The Bad: – No credible scientific evidence of safety or efficacy – Can be very restrictive • Tough to follow • Low calories = low energy, fatigue, headaches, dizziness • Low calories = lower nutrients • Low protein • Decrease in athletic performance/training • They might perpetuate disordered eating habits 5 3/22/2013 Detox Diets/Cleanses • The Bad: – Low in nutrients & phytochemicals • • • • • • • • Vitamin D Calcium Zinc Iron Anemia B12 Vitamin E Other B vitamins Omega 3 fatty acids Detox Diets/Cleanses • The Useless: – “Detoxing” is done by the body’s organs • Nose hairs & lung mucus filter dust, bacteria and allergens • Skin is a protective barrier against harmful substances • Kidneys filter 2 quarts of waste per day – excreted in urine • Liver metabolizes drugs and filters blood before it circulates to the rest of the body Detox Diets/Cleanses Done Right • Short term • Help clients find the cleanse that will do the least harm • Consider workouts • Do not cleanse while recovering from an injury or illness 6 3/22/2013 Gluten is Evil • • • • • We can’t digest gluten Most people are gluten sensitive Eating gluten free = weight loss Grains are poison Gluten free = better athletic performance 7 3/22/2013 What is Gluten? • The major storage protein in wheat • Made from glutenin & gliadin – wheat • Durum, semolina, spelt, kamut, malt, couscous, bulgur, triticale, einkorn, faro – rye – Barley Immunomodulatory activity Cytotoxic (cell destruction) Activity Gut Permeating activity Alessio Fasano Physiol Rev 2011;91:151‐175. Where is Gluten? 8 3/22/2013 Where is Gluten? • Cereal extract • Dextrin/maltodextrin (USA products usually okay – derived from corn) • Gelatinized starch • High protein flour • Hydrolyzed vegetable/plant protein • Imitation seafood • Modified starch • Natural flavors • Texturized vegetable protein List from Rachel Begun, MS, RD Celiac Disease • Autoimmune disease that occurs over time • Cause: Genetic susceptibility + gluten • Rice, buckwheat, corn, millet & other carb rich foods – do not contain gluten – may contribute to escalating symptomology in sensitive individuals by creating/sustaining inflammation 9 3/22/2013 Celiac Disease • Inflammation & Damage to the small intestine & other organs • Destroyed intestinal villi = impaired nutrient absorption Celiac Disease • Increased prevalence over the years (1 in 133 in not at risk groups) • Over 300 symptoms – Classic – gastrointestinal issues (most do not have GI symptoms!) – Most common in adults – anemia • Other autoimmune diseases common Iceberg Model – Prevalence of CD Patients with clinically overt celiac disease Patients with undiagnosed, silent celiac disease BMJ 1999;319;236. Patients with Latent CD (potential to develop the disease) 10 3/22/2013 Celiac Disease • Most people with celiac undiagnosed • Diagnose before treating!!! – TTG (IgA) – 90 – 98% sensitivity, 94‐97% specificity – At least 4‐6 intestinal biopsies including at least one of the duodenal bulb • Rx: Lifelong avoidance of gluten (10 mg/day max) Gluten Problems • Gluten Sensitivity – No standardized test – Identification based on symptoms + avoidance – If you feel bad, stop eating it Why the Rise in Prevalence? 1. How we grow and process wheat – 1961 – high yield wheat produced through fertilizers – yield = nutrients yet greater starches and glutens – Heavy use of fertilizers = rugged wheat that survived drought and disease – Genetic variety of wheat that is much higher gluten stood out. 2. How we turn wheat into flour – Disassemble it and put it back together J Agric Chem 2009 11 3/22/2013 Is Gluten Bad for Everyone? • Dr. Fasano – Wheat, rye, barley – @ 10,000 years ago – Part of the gluten chain cannot be digested (Gliadin is toxic) – Leaky gut Leaky Gut CD Autoimmune Diseases Tight Junctions – “intestinal glue” Dr. Fasano Is Gluten Bad for Everyone? • Dr. Fasano continued: – “Gluten is a chronic, modern‐day poison.” – Grains are not good for us – Paleo diet is intrinsically “gluten free” – No such thing as “gluten free.” 12 3/22/2013 Is Gluten Bad for Everyone? • No stats on prevalence of: – Gluten sensitivity – Wheat allergies – Potential link between undiagnosed CD and autoimmune diseases • Dr. Guandalini – Those without celiac disease can easily enjoy gluten with no problem Considerations before going Gluten Free • Celiac disease and tested? • Restricted diets are difficult to maintain • Gluten free foods are expensive yet many are nutritionally empty Soy Will Rob Your Masculinity! 13 3/22/2013 The Culprit: Isoflavones • Plant defense • Hormonal and nonhormonal properties • Some concerned about chronic exposure and endocrine system Soy De‐Masculinizes a Man • Many purported health benefits • Some studies show adverse effects – Rodent and in vitro studies • Studies on soy and reduced risk of breast and prostate cancer examined if results due to decreases in estrogen and testosterone – Majority of studies – soy protein or isoflavones ‐ no effect on hormone levels – Due to another mechanism Mark Messina, PhD, RD Soy & Masculinity • Very high exposures to isoflavones: – cause infertility in animals – animals metabolize isoflavones differently – Not seen in humans • One small pilot study: – Soy consumption associated with lower sperm concentration • Clinical trials – isoflavones have no effect on sperm concentration or quality Gastroenterology 1987;93:225‐33. J Agric Food Chem 1990;38:1530‐4. J Nutr 2002;132:3577‐84. Br J Nutr 2002;132:3577‐84. 14 3/22/2013 Soy and Fertility Study • Pilot, Observational Study 99 men in a fertility clinic questionnaire about how often they ate soy foods over a 3‐month period majority of men who ate soy had sperm concentrations within normal limits Hum Reprod 2008;23:2584‐90. Soy & Fertility Study A few at the higher end of the soy intake range had a low sperm concentration Effect of soy foods on sperm was greater in overweight and obese men Soy foods and isoflavone intake showed no relationship to total sperm count, sperm motility or other measures of fertility Soy & Testosterone • Meta analysis – 15 placebo‐controlled treatment groups – Included studies with adult men who consumed soy foods, isolated soy protein, isoflavone extracts – No significant effects of soy protein or isoflavone intake on: • • • • Testosterone Sex hormone‐binding globulin Free testoFree androgen index sterone Fertil Steril 2010;94:997‐1007. 15 3/22/2013 Soy & Fertility • Isoflavones are phytoestrogens chemical structures similar to estrogen not estrogen! No effect on estrogen or testosterone found in plant‐based foods – soy & legumes Soy Food Benefits • Soy protein – Lowers LDL cholesterol by 4-5% • Each 1% drop in LDL lowers heart disease risk by 1-2% – Replace higher saturated fat foods – may reduce heart disease risk by 10% or more – Does increase muscle protein synthesis and may prolong the anabolic window Am J Clin Nutr 2009;89:1155‐1163. J Nutr 2009;139:796S‐802S. We Don’t Need Dairy 16 3/22/2013 Dairy Controversies • We are the only mammals who drink another animal’s milk • The hormones in milk cause kids to mature faster and make us fat • Human’s haven’t evolved enough to digest dairy • Most people are lactose intolerant • We don’t need dairy for calcium Hormones in Milk • All milk including human breast milk contains hormones • Some cows given recombinant bovine somatotropin (rbST) (also naturally produced by cows) • Pasteurization destroys 90% of bST • Remaining bST broken down into trace inactive fragments by enzymes in the GI tract • bST is species specific – biologically inactive in humans Food Rev 1994;17:27‐31. Science 1990;249:875‐884. We Can’t Digest Dairy • Lactose Intolerance – Lactase enzyme deficiency or low activity – Incomplete digestion of lactose (sugar = glucose + galactose) – Primary ‐ Happens over time after age 2 – Secondary – injury to small intestine – GI upset – More common in African Americans, Hispanic Americans, Asian Americans, American Indians Lactose Intolerance. National Digestive Diseases Information Clearinghouse. 2006. 17 3/22/2013 Lactose Intolerance • Hydrogen breath test – lactose loaded beverage (undigested lactose = hydrogen) • Stool acidity test – more common in infants and young kids Managing Lactose Intolerance • Cheese – less lactose • Yogurt – good bacteria digests some of the lactose • Slowly, gradually increase dairy to build tolerance • Consistently consume some dairy with a meal – body is used to handling it • Lactaid Dairy Controversy Calcium & Vitamin D: – Most important nutrients to maximize the development of peak bone mass – Milk is the #1 source of calcium, magnesium & vitamin D in all people over the age of 2 • Contains other bone building nutrients – phosphorus, zinc, potassium 18 3/22/2013 • Meeting daily calcium needs with leafy greens • Not as bioavailable as calcium from dairy • 4 cups of cooked spinach /day • 8 + cups raw greens • Other vegetarian sources • Soy, rice, almond milk • Shake the container • Vitamin D2 not D3 Is Protein Bad for Bone?? • Protein makes up about 50% of bone volume and 33% of mass • Truth or myth: High protein diets and calcium loss – Not observed with food sources of protein – 30% calories from protein – no increase in calciuria – 2.1 g/kg bodyweight protein, urinary calcium increased but, intestinal absorption increased. • No truth that animal based proteins are bad for bone or vegetable based proteins are better for bone Am J Clin Nutr 2008;87: 1567S-70S. Dairy • Countries that don’t consume dairy have good bone mineral density – Other factors affecting bone health • Meta analyses of Alkaline vs. Acidic Diets and bone – Linear association between calcium excretion and acid load in the diet but… – This does not mean the excreted calcium came from bone or that this type of calciuria contributes to the development of osteoporosis – Promotion of the alkaline diet to prevent osteoporosis not justified by the research – High phytic acid and oxalic acid Osteo Int 2001;12:493‐9. J Bone Miner Res 24;1835‐40. Am J Clin Nutr 2008;88:1159‐68. 19 3/22/2013 Artificial Sweeteners are Poison Sweet Substitute or Toxic Ingredient? • They trick the body into preferring sweet foods/beverages • Side effects: – Headaches – decreased testosterone – increased cancer risk – Weight gain Sweet Substitutes? • Nutritive & non‐nutritive sweeteners must be: 1. GRAS • History of safety & common use in food prior to January 1, 1958 2. Food Additive • • Provide FDA w/ chemical identity and composition as a food additive Must be evaluated for safety & use in foods & beverages 20 3/22/2013 Not so Sweet Scrutiny ‐ Saccharin • Made from methyl anthranilate, (in grapes) • In cosmetics, chewing gum, candy, beverages, cake mixes, pharmaceuticals, pink packets • In the 1970’s rats given high dose saccharin got bladder cancer – Mechanism irrelevant for humans • Saccharin doesn’t cause cancer in humans • Not metabolized in the body, doesn’t raise blood glucose Aspartame • Phenylalanine, aspartic acid, methyl ester group • Doesn’t accumulate in the body • Causes a very slight increase in blood glucose Diet Soda = Obesity • Data from the San Antonio heart study – – – – > 5,000 people, 7‐8 yr follow‐up All soda drinkers gained weight but… Diet soda drinkers gained more weight The more diet soda, the greater the weight gain • Framingham Heart Study – > 9,000 people – 4 year follow‐up – Those who drank sugar sweetened and zero cal soft drinks more likely to gain weight 21 3/22/2013 * Observational Studies Is Natural Better? • • • • Stevia Sugar alcohols Lao Han Go Fibers – Inulin We Can Get all of Our Nutrients From Food 22 3/22/2013 We Can Get all Nutrients from Food • • • • True, sort of Nutrients of Concern Specific Disease States/Conditions Too much of a good thing? – Yes, antioxidants 23 3/22/2013 Nutrient Deficiencies • Prevalence of Vitamin D deficiency (NHANES 2005 ‐ 2006) – 4495 adults – serum 25‐hydroxyvitamin D concentrations < 20 ng/ml – 41.6% deficient • 82.1% blacks • 69.2% Hispanics • Prevalence of Iron deficiency – 2% in men – 9‐10% in white women – Nearly 20% in black and Mexican‐ American women Nutr Res. 2011 Jan;31(1):48‐54 Am Fam Physician. 2007 Mar 1;75(5):671‐678.. My Rules • Never place your dietary restrictions, allergies, intolerances, nutrient deficiencies, diseases etc. on your client • Speak openly from what the science says • Don’t boil down your client’s issues into one food, one ingredient, one meal etc. • Remember many of your clients give you half the story! • Favor Progress, Not “Perfection” 24 3/22/2013 Marie Spano, MS, RD, CSCS, CSSD @Mariespano 25
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