The FDA has recently held a webinar with a representative of the agency, a nutritionist, and a representative of the pet food industry to provide an update on the state of the ongoing investigation of certain diets and possible heart disease risk. Here is the link to the recording along with my summary notes.
Martine Hartogensis– FDA
Cardiologists reported ~ 150 cases dilated cardiomyopathy (DCM) in atypical breeds to FDA
FDA noted ~ 30 case reports had been filed with them with dogs on grain-free and legume/tubers containing diets.
FDA followed up on 30 cases and did not see low taurine in the foods but did find low taurine in some of patients
Now total of 160 dogs reported with DCM (149 case reports), 39 deaths, mostly from 2017-2018
8 cats reported (in 4 cases) with 1 death, these are from 2015-16
90% of dog cases had grain-free/legume/tuber-containing diet history
Prospective study ongoing checking foods and dogs for cysteine/methionine/taurine
Lisa Freeman– Tufts
DCM 2nd most common canine heart disease after valvular disease
A variety of different diets and breeds linked to taurine deficiency/DCM over the years
Dr. Sterns at UC Davis has been looking at taurine-deficient DCM in Golden Retrievers for about 3 years
Some dogs with DCM on grain-free or legume-containing diets are taurine deficient but even those that aren’t sometimes improve on taurine supplementation
Roughly 3 groups of dogs-
- Typical breed primary DCM cases (Boxers, Dobermans, etc.)
- Taurine-deficiency DCM in both typical and atypical breeds
- Diet-associated DCM with normal taurine levels in either typical or atypical breeds. These are not just grain-free but also “boutique” and exotic protein diets (“BEG” diets). The majority of DCM cases on these BEG diets have NOT been taurine deficient.
May be deficient in taurine or precursors, decreased absorption, increased elimination, other variables
All DCM cases should have full diet history, screen for taurine, supplement taurine whether low levels or not, change to more typical diet
Greg Aldrich– KSU/Industry
Lots of manufacturers are now adding taurine to diets even though it is not clear this is the answer
Grain-free diets are ~ 25% of the dog food market, so not going away
Even with a large supply of relevant amino acids in meat meal, if the bioavailability is not high enough there may not be enough on an as-fed basis
Legume seeds/pulses lower in methionine than traditional cereals and lower bioavailability. They also have some soluble fibers in them which can influence bacterial fermentation in the colon which can deplete taurine.
Potatoes don’t really contribute to the protein in a diet, so unclear how any association with taurine levels might work
FDA uses cat taurine levels as guideline since likely to be higher than dogs need, so in foods identified as not deficient this means they meet the cat requirement
Number of reports has, of course, increased since FDA announced it is investigating this, and many do not appear to be genuinely related to this issue; The 160 dogs mentioned are confirmed DCM diagnoses by echocardiogram.
Even though most notable association has been legumes/tubers/boutique diets the FDA is looking at other possible causal factors but so far no other clear signals. No clear pattern related to particular protein source in diets.
BEG Diets= boutique (small manufacturers but not willing to define specifically), exotic ingredient, grain-free diets. Reiterated majority of DCM cases on these diets have not been taurine deficient.
Worth bearing in mind that < 200 animals known to be affected out of ~100 million pet dogs, so scale of the problem does not yet appear very large
Bear in mind taurine may not be the whole story so adding taurine to foods or supplementing individual dogs may not be appropriate if it turns out some of these cases are associated with other risk factors
Recommendation to pet owners is to speak with veterinarian about nutrition since a lot of the information and advice people seek and use to guide feeding comes from marketing, pet food stores, and other sources without necessarily a sound, science-based approach.
Very few reports from countries outside the U.S. at this point.