Thread by @GardnerPhD

Apologies for not responding sooner with specifics to @bigfatsurprise @ProfTimNoakes with specifics.
Here are some......

Fundamental flaw
Yes, RCT’s are design w/ highest causal inference
But many topics can’t be studied w/ RCT
Can’t randomly assign & follow until morbidity/mortality:
*Cigarettes & lung cancer
*Parachutes when sky diving
*Vegan/Vegetarian
Lack of RCT does not = lack of evidence

Claim about review of nutritional epi findings-“0% [to 20%] confirmed in clinical trials”
Refuted?
Or not conducted?
There are very few RCT nutrition trials w/ hard outcomes
Most are done with supplements, not foods
Not surprising that few are “confirmed” if few are “conducted”

Assessment
FFQ’s have methodological limitations
So do multiple 24-hr recalls & records
All 3 can be done with large n’s over long time

Incarcerating and feeding people much more rigorous
Small n’s & short durations are limitations

Don’t dismiss until they can be replaced

Beware over-reliance on meta-analyses
In some areas, there are now more meta-analyses on a specific topic than the # studies pooled.
Meta-analysis without content experts problematic (not uncommon)
Garbage in – garbage out
Kraemer, Gardner et al. Psychol Methods,1998;3(1):23-31

Misunderstood role of nutritional epi
For most food & nutrition topics assessing connections btwn FOODS & morbidity/mortality, there are no RCT’s, never will be
Obs epi with cohorts is important source of HARD OUTCOMES data
w/o that we would be left with only risk factor studies

Inaccurate summary of 2019 ADA Nutrition Update (I’m on panel/co-author)
Patterns that reduce risk of diabetes
Mediterranean, vegan/vegetarian, low-fat & DASH
Patterns that reduce HbA1c
Mediterranean, vegan/vegetarian, low-carb, VLCD
Read Table 3

Graph showing consumption of animal food ⬇️ w/time, w/ parallel ⬆️ in obesity & diabetes
“Animal” in graph = beef, whole milk, eggs, animal fats, butter
Where is chicken?
Increase in chicken consumption has been dramatic, same time period
Others are missing
Selective list

Nutrition textbooks & position statement from Acad Nutr & Dietetics conclude plants can provide all nutrients-supplements not necessary
Vegans don’t require supplements (B12 maybe, but not just from supps)
Veg*ns & Omnivores w/ poor or limited food choices, can benefit from supps

Lyon ❤️study
Not just margarine
“⬆️ bread, root vegetables, green vegetables, fish,
⬇️ meat (beef, lamb & pork replaced w/ poultry)
No day w/o fruit
Butter and cream replaced with high oleic margarine provided by study”

Not just France - also Spain, Italy, and North Africa

I consider many of those significant and serious.
I agree some of those are petty and distracting.

Disagreements aside...

Best veg*n better than worst omnivore
Best omnivore better than worst veg*n
Best veg*n & best omnivore have similarities
⬆️whole foods & veggies
⬇️added sugar & refined grain
Would prefer to focus on agreements
Much to be done there

Safety glasses off