Découvrez des podcasts liées à The OneVetMed Podcast with Dr Robert Gaston. Explorez des podcasts avec des thèmes, sujets, et formats similaires. Ces similarités sont calculées grâce à des données tangibles, pas d'extrapolations !
Episode 9: Nutritional Deficiencies and Dietary Supplements – Part 2
dimanche 2 mars 2014 • Durée 25:45
Episode 9: Nutritional Deficiencies and Dietary Supplements - Part 2
Answering the questions about use of nutritional supplements:
How do we recognize/suspect the need?
When should we use nutritional supplements?
In order to better recognize and understand nutritional deficiency, it helps to review some basics of nutritional research
Methods: Experimental and observational study used to identify deficiency syndromes
Often begun with the observation that certain foods influenced active disease processes
Limes used to prevent and treat scurvy
Efforts directed toward identifying the beneficial substance(s) in those foods.
The primary focus of the early research was on vitamins
Philosophy of Nutritional Scientists: Synthetic Reproduction of ‘Active’ Ingredients
Early research failed to recognize the chemical complexity of foods
Assumed that foods are simple mixtures of a few easily identified chemical constituents, which, through modern chemistry, can be easily reproduced
Nutritional Research: Defining Nutrient Deficiencies
(introduced this idea in episode 2 when describing how “essential” nutrients are identified for pet food.)
Defining disease syndromes of nutrient deficiency relies on the total exclusion of a single nutrient, such as a vitamin, over short-term.
The manipulated diet produces the classical signs of disease associated with the absence of that nutrient.
Understanding nutritional studies
Observational (dietary intake)
Diets containing large amounts of foods high in β-carotene (yielding high blood levels of β-carotene) have been associated with decreased risk of cardiovascular disease and several types of cancer
Intervention trials (supplementation)
Different vitamin sources affect outcomes of clinical studies
Supplementation trials may yield contradictory results
Example: Synthetic β-carotene supplementation
Nutritional Research-The Key to Understanding ‘Conflicting’ Results
The Case Against Vitamins Wall Street Journal March 20, 2006 p. R1, R3
http://www.mythyroid.com/documents/WSJVitamins.pdf
http://online.wsj.com/article/SB114235146814497776.html
Prevalence - 70% of households buy vitamins
$7 Billion spent on vitamins in 2005
Rationale
Boost immune system
Protect heart
Decrease risk of cancer
Results
“May be doing more harm than good”
Detrimental effects
Cancer promotion
Increased risk of heart failure
Last year, Johns Hopkins University researchers in Baltimore published a shocking finding. After reviewing the data from 19 vitamin E clinical trials of more than 135,000 people, the analysis showed high doses of vitamin E (greater than 400 IUs) increased a person's risk for dying during the study period by 4%. Taking the vitamin E with other vitamins and minerals resulted in a 6% higher risk of dying.
Since the analysis was published, another study of about 9,500 patients evaluated long-term use of 400 IUs of vitamin E daily. The study didn't show any statistically meaningful differences between vitamin users in terms of cancer, heart attacks or stroke, but the vitamin E takers had a 13% higher risk for heart failure.
"The psyche of the U.S. population is that a nutraceutical can't be harmful and might be helpful, so why not take it?" says Dr. Klein. "That thinking is just not correct.
What is going on?
“Nobody knows why high doses of vitamins taken as pills might cause harm”
“What is clear, however, is the important role a healthful diet plays in preventing illness”
The critical difference is that vitamin complexes and phytochemicals found in food are fundamentally different than isolated pharmaceutical doses of vitamins.
Observation vs. Intervention: Detrimental Effects of Synthetic Beta Carotene
β-carotene initially appeared to be the associated link between lowered cancer...
Episode 8: Pet Dental Disease – Care and Maintenance
dimanche 9 février 2014 • Durée 16:32
Episode 8 is all about KEEPING YOUR PETS TEETH CLEAN
A continuation of Dr. Gaston’s look at nutritional deficiencies and dietary supplementation. In this episode Dr. Gaston explains the apparent contradictions between many nutritional studies which lead to so much confusion over whether supplements are good or bad. He also presents some examples of examples of nutritional deficiency to help change our perspective on what a real-world nutrient deficiency looks like.
A healthy mouth is important for overall health … and more pleasant when your pet doesn’t have bad breath
Chronic inflammation from gingivitis and periodontal disease is detrimental to health of people and animals
Chronic inflammation can affect many areas of the body
Bacteria entering the circulation through inflamed gum tissue can adversely affect heart valves, kidneys, liver, etc.
Plaque:
Many bacteria in the mouth
Bacteria and saliva form a slick coating (‘biofilm’) on the surface of the enamel
On a clean tooth surface, plaque begins accumulating in less than 30 minutes
Tartar:
Mineral from saliva incorporated into biofilm of plaque
Tightly bound to enamel surface
Process begins within 48 hours
Gingivitis
Periodontitis
Heavy accumulation of tartar, red inflamed gums
Loss of periodontal ligament, alveolar bone, and receding gumline
Controlling plaque and tartar
Self-cleaning architecture of dog and cat teeth diminish plaque and tartar accumulation
Processed pet foods contribute to plaque and tartar accumulation
Canned – soft consistency
Dry kibble-type foods – brittle
Fibrous/abrasive food stuffs assist in self-cleaning action
Scrub surface of tooth to gum line
Bones, turkey necks, chicken necks
Vegetables – carrots, celery, broccoli stems
Other factors influencing gum health
Oral Flora
pH
Raw diet
Unknowns and inconsistent results
Size of dogs
Brushing
Brush
Manual
Motorized spin brush
Dentifrice
No Xylitol
No Flouride
Hand scaling
General anesthesia with ultrasonic scaling and polishing
Thorough scaling and examination
Extractions and radiographs as needed
Examination and evaluation of health or specific concerns that may affect safety of anesthesia
Pre-anesthetic blood work
Age limitations?
Episode 7: Nutritional Deficiencies and Dietary Supplements
dimanche 9 février 2014 • Durée 19:30
Episode 7: Nutritional Deficiencies and Dietary Supplements
Public Interest in Nutritional Supplementation
50% of the U.S. adult population uses dietary supplements
1990-1997 400% growth in dietary supplement sales for humans
Currently growing at 15% per year
$37 billion annually
85% of regular supplement users believe that dietary supplements are good for health
82% of Americans would try herbs for terminal illness
{ http://www.cfsan.fda.gov/~dms/fdsupp.html; Boothe DM. 2004 Vet Clin Small Anim 34:7-38 ; Blendon RJ. 2001 Arch Intern Med 161:805-810 }
Similar interest in supplement use for pets
30% of pet owners have used or have considered using dietary supplements
90% of veterinarians sell some type of herbs or nutraceuticals
$20-50 million in annual sales
{Boothe DM. 2004 Vet Clin Small Anim 34:7-38}
Important Questions Concerning Nutritional Supplements
What are nutritional supplements?
Terminology, Definitions, Contents
Why do we need nutritional supplements?
Evidence for nutritional deficiencies - When should we use nutritional supplements?
How do we recognize/suspect the need?
What nutritional supplements should we use? - What kind of nutritional supplement is best?
How do we use nutritional supplements?
Conventional Thinking About Nutritional Supplementation
“The proper role of a supplement is to correct a diagnosed nutrient deficiency”
{Small Animal Clinical Nutrition 4th Ed p. 116}
However, diagnosis is difficult with current tools and difficult to recognize based on conventional definitions of deficiency
“ The most common form of veterinary supplements is a wide variety of vitamin and vitamin-mineral combinations that are used by 10% of animal owners”
{Small Animal Clinical Nutrition 4th Ed p. 116}
Predominantly consist of isolated, or synthetic, vitamins
“Routine use of vitamin mineral supplements is not needed when a dog or cat eats typical commercial pet food”
“…dogs and cats consuming commercial dry rations were ingesting from two to five times the daily allowance of vitamins”
{Small Animal Clinical Nutrition 4th Ed p. 116}
They are already receiving potentially excessive amounts of isolated, or synthetic vitamins
The conventional approach to nutritional supplementation is to provide more of the same isolated and synthetic nutrients that are already present in high amounts in the pet foods, expecting a better outcome
It has been claimed that insanity is continuing to do the same thing, expecting a different result
Confusion in Terminology: What Are Nutritional Supplements?
Food: (according to section 201(f) of the Food, Drug, and Cosmetic Act)
“a raw, cooked, or processed edible substance, ice, beverage, or ingredient used or intended for use or for sale in whole or in part for human consumption”
“articles used for food or drink for man or other animals, chewing gum, and articles used for components of any such articles.”
This includes “dietary supplements and dietary ingredients”
{ http://www.cfsan.fda.gov/~dms/fsbtac13.html http://www.cfsan.fda.gov/~dms/fc01-1.html1 http://www.cfsan.fda.gov/~ear/ims-a-30.html}
Drugs:
“articles [food or non-food] intended for use in the diagnosis, cure, mitigation, treatment, or prevention of disease in man or other animals”
“ articles (other than food) intended to affect the structure or any function of the body of man or other animals”
{ http://www.cfsan.fda.gov/~dms/fsbtac13.html http://www.cfsan.fda.gov/~dms/fc01-1.html1
http://www.cfsan.fda.gov/~ear/ims-a-30.html}
“Medical Food” originally applied to humans
For dietary management of a disease or health condition
Under the direction of a physician
Label must state that the product is to be used to manage a specific medical disorder or condition
Episode 6: Diet Recommendations
vendredi 31 janvier 2014 • Durée 29:35
Episode 6: Diet Recommendations
Many choices in pet foods
Dizzying array in the pet store from the least expensive to the more expensive and ‘holistic’ foods
What is a ‘holistic’ food?
Which one to choose? Why? Two primary concerns:
Nutritional quality
Safety
Recent safety concerns with commercial foods – What’s in the bag?:
Melamine
Aflatoxin or other fungal toxins
Pentobarbital or other drug residues
2002 FDA veterinarian Newsletter Vol XVI, No III http://www.fda.gov/AnimalVeterinary/NewsEvents/FDAVeterinarianNewsletter/ucm110419.htm
“After finding that the low levels of pentobarbital that dogs might receive through food are unlikely to cause them any adverse health effects, FDA officials did not think that further research into the issue was necessary.”
Bacterial contaminants
Human Salmonella Infections Linked to Contaminated Dry Dog and Cat Food, 2006-2008
Seventy-nine case-patients in 21 states were identified; 48% were children aged 2 years or younger.
A low attack rate supports the hypothesis that infection might have resulted from practices in a limited number of households.
One possibility is that the number of organisms was magnified in some households because of, eg, cross contamination in the kitchens or irregular cleaning of pet food bowls, which might promote bacteria growth.
In addition, illness may have occurred primarily in persons who were more susceptible to infection with a small number of organisms.
Illness was not reported in dogs or cats from case patient households, although the outbreak strain was cultured from several stool specimens from dogs who ate contaminated dry dog food.
Some children may have become ill from contact with a pet carrying the outbreak strain.
Prevalence of isolation of Salmonella from feces of healthy dogs is reported to be between 1% and 36%, and from healthy cats between 1% and 18%.
Dogs and cats may shed Salmonella in the feces for as long as 12 weeks, and shedding may be intermittent, 11 so the risk of infection could continue for extended periods.
In addition, it is thought that Salmonella can survive for extended periods in dry dog and cat food, as it can in similar dried foods such as cereals.
Forty-three million US households (37%) own dogs and 37.5 million (32%) own cats, and many pet owners feed the animals dry pet food.
…dry pet food, the most common pet food fed to dogs and cats, is not manufactured to be a sterile product.
Typically, a more drastic heat treatment is required to destroy Salmonella in dried food products.
Since 2006, according to the FDA, at least 13 recall announcements involving 135 pet products (eg, dry dog food and cat food, pet treats, raw diets, and pet supplements) have been issued because of Salmonella contamination.
No human illness was associated with these other pet food recalls.
The recommendation to wash hands is the most important prevention step for reducing the risk for disease transmission.
{http://pediatrics.aappublications.org/content/early/2010/08/09/peds.2009-3273.full.pdf }
http://www.dogfoodadvisor.com/dog-food-recalls/
A total of 49 individuals (47 individuals in 20 states and two individuals in Canada) infected with the outbreak strain of Salmonella Infantis were reported.
Among the 24 patients with available information, 10 (42%) were hospitalized. No deaths have been reported.
Epidemiologic and laboratory investigations conducted by officials in local, state, and federal public health, agriculture, and regulatory agencies linked this outbreak to dry dog food produced by Diamond Pet Foods at a single production facility in Gaston, South Carolina.
Multistate Outbreak of Human Salmonella Infantis Infections Linked to Dry Dog Food (Final Update)
http://www.cdc.gov/salmonella/dog-food-05-12/pet-owners-info.html
Salmonella Infection (salmonellosis) and Animals
Episode 5: Recognizing Nutritional Deficiency: 2 clinical examples
Presenting two examples of nutritional deficiency
Not classical nutritional/vitamin/mineral deficiency syndrome
Lack of classic signs = “subclinical” deficiency
Veterinarians need to increase their level of suspicion that illness may be related to nutritional problems
Aspen
Presented 4/02: 13 year old spayed female Labrador retriever-shepherd mix
The owner – my brother - noticed weakness and exercise intolerance
Rapid progression over two-three weeks
Syncope/collapse episodes with mild exertion
Became unable to walk more than a few steps without resting
Diet
Science Diet®
Chemistry Profile, complete blood count and Thyroid hormone level all normal
Chest x-rays were normal
5/9/02 Evaluation of ECG via Telemedicine consultation with cardiologist
HR 50 BPM
Diagnosed as complete heart block
Possible degeneration, fibrosis, or inflammation of AV node
Recommendation: Echocardiogram and possible pacemaker implant
Telephone consultation (Oregon - Ohio)
Recommended treatment
Nutritional support for cardiac function, electrical conductance, muscle function, general nutrition
Cataplex® B (Standard Process)
L-carnitine (Pure Encapsulations)
Vasculin® (Standard Process)
Cardio-Plus® (Standard Process)
Catalyn® (Standard Process)
Calcifood® wafers (Standard Process)
Improvement noticed within several days after starting supplementation
Continued progress over initial 4 weeks of supplement use
Returned to normal activity level within 4 weeks
8/6/02 Echocardiogram
Anatomically normal heart
Normal contractility
Severe bradycardia (32 beats per minute) with continued complete heart block
2/25/03 progress exam
Clinically normal 14 yr old dog
Repeat ECG: unchanged from 5/02
Aspen running up and down long hill in yard with children
Continued supplements as initially prescribed
Continued Science Diet
9/20/05 progress exam
Nearly 17 yrs old
Stiff and slow moving, nearly blind, hearing loss, developing urinary incontinence
Continued bradycardia due to electrical abnormality
No syncope
Had more stamina than 4/02 prior to supplementation
12/05 euthanized due to deteriorating physical condition, incontinence, arthritis, etc. – no syncope, no heart failure
Gypsy
Presented 8-8-05 - 4 year old spayed female golden retriever mix
Consultation concerning autoimmune disease, open wound on rear end, and generally declining condition
Owner concerned that Gypsy was dying and wanted to incorporate complementary approaches
History:
Developed severe bone or joint pain at 9 months old
Lame, crying when touched
Developed immune myositis - diagnosed via muscle biopsy November 2002
Presented as acute-onset muscle pain and inability to open mouth
Muscle atrophy developed subsequently
Prednisone therapy initiated ( and continued daily since)
4-18-03 Giardia with severe diarrhea and vomiting
Several teeth extracted due to loosening/periodontitis
Seasonal exacerbations of muscle inflammation and dysfunction x 3 yrs.
Approximately October/November 2002, 2003, 2004
Allergic component?
Faithfully vaccinated (yearly)
Last vaccine 3-8-05
Flatulence; owner feels that abdomen is hot and distended; other dog eats Gypsy’s stool
Medications:
Prednisone 10 mg once daily (continuous use since Nov 2002),
Thyroxine 0.7 mg twice daily
Blood Chemistries and CBC
AlkP AST ALT GGT P Gluc Amyl WBC Neutr
8/8/05 1430 72 461 80 4.1 144 16.9 83%
5/17/05 2738 75 596 430 6.2 44 224 20.6 83%
4/23/05 2842 75 612 410 5.5 18 248 20.7 86%
Episode 4: Nutrition – Does heat-processing adversely affect nutrition?
jeudi 12 décembre 2013 • Durée 18:30
Episode 4: Nutrition – Does heat-processing adversely affect nutrition?
Continuing to examine the big concepts in pet nutrition
Effects of heat-processing in commercial foods-
Manufacturing affects nutrient quality and bioavailability
Extruded 320ºF
Canned 500ºF
Heating effects: Alterations in protein structure
Maillard reactions
Bonding of sugar (glucose, fructose, lactose, maltose) with free amino group (such as lysine)
Digestive enzymes do not cleave the peptide bond adjacent to the amino acid with attached sugar molecule
May increase microbial degradation of taurine in colon
Affected proteins are of no nutritional value
Allergenic?
Other “unusual crosslinking” of amino acids and peptides which result in compounds “not found in nature”
“These compounds are not well-used by animals”
“Processing EFA in pet foods may affect their biological activity”
{Small Animal Clinical Nutrition 4th Ed pp.55, 61}
Heating effects: Alteration of fatty acids
Trans configuration
Metabolized for energy and incorporated into lipid storage
Cannot function as EFA’s because they are not further metabolized to eicasanoids
C18:1 trans isomers inhibit hepatic carnitine and lead to increased liver triacyglycerol by lowering hepatic oxidation of fatty acids
{Giudetti AM, Beynen AC, et. al. Hepatic fatty acid metabolism in rats fed diets with different contents of C18:0, C18:1 cis, and C18:1 trans isomers. Br J Nutr. 2003 Nov;90(5):887-93}
More pieces to the puzzle of heat processing effects:
Carprofen half-life in cats
Recent study showed variation 17 hours to 44 hours
Difference in liver enzyme activities attributed to diet
Fresh, whole foods enhanced liver detoxification
Commercial diets detrimental effect
Propranolol half-life in cats
Study done ~20 years ago showed variation from 1-2 hours to >12 hours
Diet effects as seen with carprofen
Major pet food manufacturer had no interest in investigating why the variation in metabolism
{Dr. William Muir, lecture delivered at Veterinary Chiropractic Convention April 2003, and personal conversation.}
Study of food allergy in dogs
After successful elimination diet, introduced commercial canned or kibble ‘equivalent’ diet
25% recurrence of clinical signs (pruritus)
“With every treatment diet tried, some percentage of dogs redeveloped pruritus.”
Explanations/Speculations
3-D protein structure altered with heating?
Decreased digestibility?
Loss of important co-factors?
{Rosser, EJ. Diagnosis of food allergy in dogs. JAVMA, Vol. 203, No. 2, July 15,1993 pp.259-262
Pottenger’s Cats
Nutritional study completed 1932-1942
Multigenerational study
Nine hundred cats
Four basic feeding groups
Optimum diet groups
2/3 raw meat, 1/3 raw milk, Cod Liver Oil
2/3 raw milk, 1/3 raw meat, Cod Liver Oil
Deficient diet groups
2/3 cooked meat
2/3 cooked milk (pasteurized, sweetened condensed, evaporated, metabolized vitamin D)
Effects observed with deficient diet
Dental disease
Reproductive abnormalities
Allergies
Immune disorders
Skeletal disease and osteoarthritis
Cardiac abnormalities
Renal disease
Respiratory abnormalities
Gastrointestinal abnormalities
Hepatic abnormalities
Behavioral abnormalities
Endocrine abnormalities
Ocular abnormalities
{http://www.amazon.com/Pottengers-Cats-A-Study-Nutrition/dp/0916764060 }
{http://ppnf.org/ }
Multigenerational effects – demonstrated “epigenetics” prior to understanding of gene structure or tools to examine
Studies in epigenetics reveals that food affects more than just calories and deficiencies…it alters the essence of genetic expression…in the individual…and for subsequent generations
Understanding nutrition is critical to longevity and health
{ NOVA | scienceNOW | Epigenetics | PBS }
Episode 3: A Better Understanding of a “Complete” Diet – Part 2
jeudi 12 décembre 2013 • Durée 13:37
Episode 3: A Better Understanding of a “Complete” Diet - Part 2
In Episode #2, we talked about the “complete and balanced diet” myth.
Now in Episode 3 we will look more at the issue of whether veterinarians and nutritional scientists really understand nutrition thoroughly enough to make a claim of “complete”
Are there examples of our continually improving understanding of nutrition that proves that the claim of “complete” at any point in time is always subject to revision - to be ‘more’ “complete”?
Are there complexities in food which make the Nutritional Essentiality paradigm dangerous to our pets?
Are there concrete examples of these “complete” diets causing problems in pets that were eating them?
“It is nothing short of a tragedy for a patient to be permitted to suffer from simple starvation while being given the so-called benefit of modern science in a modern hospital, and still gradually fade away by reason of some unrecognized form of malnutrition.”
{Lee R. October 23-24,1943. Malnutrition As A Primary Cause Of Disease, Lectures of Dr. Royal Lee p.32.}
Look at the relatively recent example of Taurine
Currently considered “non-essential” in dogs
Able to synthesize taurine from sulfur amino acids cysteine and methionine
Recent published reports of dilated cardiomyopathy in dogs eating “complete and balanced” diets associated with low blood taurine levels
Improved cardiac function with taurine supplementation
Prolonged survival time and withdrawal of medications other than taurine supplementation
DCM is typically progressive and fatal
{Backus, et. al. JAVMA Vol. 223, No 8, October 15,2003: Fascetti, et. al. JAVMA Vol. 223, No 8, October 15,2003}
Reported cases of DCM in dogs
Diets “met recommended nutrient profiles or passed minimum feeding protocol tests recommended by the Association of American Feed Control Officials.”
Bioavailability of methionine and cysteine appeared to be adequate for the synthesis of taurine
Diet change improved taurine status
“…Other dietary factors precluded adequate synthesis of taurine”
2 dogs fed home-prepared low protein tofu-based diet that met National Research Council requirements for adult maintenance
{Backus, et. al. JAVMA Vol. 223, No 8, October 15,2003: Fascetti, et. al. JAVMA Vol. 223, No 8, October 15,2003}
Mechanism of heart failure in taurine deficiency is poorly understood
Heritable susceptibility – genetic component
Individual biochemical variations in taurine absorption, metabolism, excretion
Lacking a necessary contributing factor?
“The variation in clinical manifestation of taurine deficiency is suggested to be a result of the variable presence of contributing factors.”
{Backus, et. al. JAVMA Vol. 223, No 8, October 15,2003}
Taurine in cats
Thought to be unimportant other than for bile conjugation until the 1960’s
Research showed that retinal degeneration in cats improved with addition of meat to casein-based diet
No change with added Vitamin A
In 1987, a connection between taurine deficiency and feline dilated cardiomyopathy was discovered
As in dogs, DCM was considered to be progressive, irreversible, fatal condition
After more research, it was found that cats require dietary taurine
What other the other signs that might be visible with taurine deficiency?
Non-specific as with some nutrients (i.e. Scurvy with C)
Poor reproductive performance – abortions, stillbirths, low birth weights
Poor growth rates
Skeletal deformities
Neurological abnormalities – degenerative changes in retina, cerebellum, and visual cortex
Compromised immune function
Hearing loss
(We will mention this same list again when we talk about Pottnger’s Cats and the benefits of raw food in Episode 4!)
BUT…Not all taurine depleted cats develop DCM
“It is, therefore, apparent that taurine deficiency alone is not sufficient to...
