Debunking Nutrition Myths
Marie Spano, MS, RD, CSCS,
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
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
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)
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
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
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
Detox Diets/Cleanses
• The Bad:
– Low in nutrients & phytochemicals
Vitamin D
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
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
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?
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
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)
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
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
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.”
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!
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.
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:
Sex hormone‐binding globulin
Free testoFree androgen index
Fertil Steril 2010;94:997‐1007.
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
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.
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
• 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.
• 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.
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:
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
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
• 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
* Observational Studies
Is Natural Better?
Sugar alcohols
Lao Han Go
Fibers – Inulin We Can Get all of Our Nutrients From Food
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
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”
Marie Spano, MS, RD, CSCS, CSSD