There is so much noise about how to live a healthy lifestyle. Detoxing, juicing, gluten-free, eating clay (a thing), high-dose supplements, etc. Much of the noise is created by celebrity culture, as I note in my book "Is Gwyneth Paltrow Wrong About Everything?" link to book. I work with our team at the Health Law Institute link to delve deep into these claims looking for the evidence (if any) is behind them. Twitter: @CaulfieldTim

My proof:

Time to sign off! Thanks to all. Fantastic Qs. Tons of fun. Hope I can do it again soon.

Answered a few more great AMAs! Thanks. Terrific community.

Must sign off again! Thanks for the great Qs. Some wonderful discussions.

Comments: 231 • Responses: 36  • Date: 

eriseley29 karma

Hello, thanks for doing an AMA!

How much if any health benefit is there in eating organic food versus conventionally grown? Any key points to note on this topic?

CaulfieldTim75 karma

Love this topic! And so controversial. Lots of passion. Wrote a brief piece about it here: Can summarize the science like this: 1) No evidence organic is significantly more nutritious; 2) slightly less certainty around pesticide issue, but still no evidence of clear harm; 3) data cutting both ways on impact on environment. This last issue is tough... I think we need to set aside our ideological biases, learn from the best practices of conventional and organic farming, and figure out how to grow healthy food in a sustainable manner ... and in a way that can feed the world.

BTW, also interesting research that has found little/no taste difference! But freshness key...

stegoh324 karma

What role do you see the government filling to help combat the social media-driven advertising done by celebrities? For example, I think I remember something about a Kardashian getting a warning letter for an instagram sponsorship. Are government tools another tool to fight this deceptive advertising/endorsements.

CaulfieldTim25 karma

Kim K and the Instagram drug ad! Yep, this is a challenge. Here at the HLI we are looking a ways to fight this kind of thing. Also bunk health claims that exploit emerging science (e.g., stem cell clinics). We need to explore way to use, for example, truth in advertising leg, professional guidelines, and, even, tort law. Here is a piece we did on fighting stem cell tourism

ec59822 karma

What's up with this eating clay thing?

CaulfieldTim40 karma

Shailene Woodley big on eating clay idea. Don't get it! There is a believe that it helps detoxify your body. 1) don't need to detoxify your body with these kind of gimmicks; and 2) no evidence clay helps! Plus... yuck.

EightBitRanger21 karma

What is your opinion on Soylent, or other 'meal replacement beverages'? Fad or feasible?

CaulfieldTim44 karma

There are individuals that, for clinical reasons, need meal replacement products. However, for healthy individuals, we should strive to get our nutrients and calories from real food. Food is complicated stuff. It is hard to pull out the good stuff and put it in a pill or supplement. Eat the apple.

andywhatever20 karma

they now say red wine is not good for us ( can we believe anything from observational studies and those who tout them -epidemiologists?

CaulfieldTim35 karma

This kind of back and forth is so interesting. The same thing has happened with eggs, coffee ... and bacon! Some data suggests that this is one reason people tune out health advice. Nutrition research is tough! Need big numbers to deal with variables. And, as you note, observational data not the best... I do think it has value, for sure. Particularly when huge N and lots of other evidence signally in same direction (as with fruit and veggies).

kittenjeju17 karma

What's the best brand of vitamins?! I want to start taking vitamin E and biotin and zinc, but I'm weary of unadvertised added extras or the products simply not working. I've taken vitamin E with success and my doctor believes in vitamins, but I want to know which brands are the very best.

Beyond that, I eat extremely cleanly (most of the time), stay hydrated with tea, and do yoga.

CaulfieldTim41 karma

I am, in general, a vitamin and supplement skeptic (but trying to keep an open mind!). History and most of the available data suggests that there is little or no health benefit for most.... unless you have a clinically identified deficiency. I don't take any. That said, interesting work on vitamin D, for sure. Data very mixed. Here is a study we did on media representations of vitamin D. Has a nice review of data... but area evolving quickly!

andywhatever13 karma

'here is a study' ... forgot the link?

CaulfieldTim29 karma

Oops. Here is our study "Representations of the health value of vitamin D supplementation in newspapers: media content analysis"

Jemma66 karma

Is there much wiggle room to this? If available data suggests they're pointless for the average individual, doesn't that mean they're pointless? Or do you think it's possible something has been missed?

CaulfieldTim9 karma

I think most in the research community agree that it is best to get your vitamins from the food you eat. Also, some evidence that some vitamins/supplements may cause harm (particularly if taken in large doses). But, as noted, research continues around vitamin D. And some in research community do think we should be supplementing... particularly in places like Edmonton! Here is an interesting piece from JAMA on point

Jemma64 karma

Thank you! My dad has done some vitamin D supplementing (with direction from a specialist) and he swears by it. I know very little, I'll have a read!

CaulfieldTim14 karma

Well, many in clinical community believe in its value. So, the d-bate continues! There are several big clinical trials happening right now. Should know more in the future. I'm keeping an open mind!

Doc-in-a-box3 karma

Dr. Gregory Plotnikoff is our local vitamin D expert and endorser. There are certainly some one-off studies that suggest vitamin D benefits, such as how important ample levels of vitamin D are for attachment of the fetus to the uterine wall (implication in miscarriages), and the fact that breast cancer survivors are more likely to recur their cancer in the presence of D deficiency.

On a personal level, as a doc (and presumably science-minded brain), had D levels in single digits and had a significant vitality and mood improvement with supplementation. This is definitely anecdotal, but the studies aren't really targeting populations with very low levels of D (which is common in my part of the world).

CaulfieldTim4 karma

Yes, this is a critique I've heard too. And that all the big studies are observational. All the trials too small and poorly run. There are a few big ones on the go now. This is an interesting systematic review from BMJ:

Come_Along_Bort17 karma

Do you think having a private health care market, makes it easier for shysters to operate? I ask simply because in the UK we have a governing body known as NICE who approve drugs for government funding (i.e. free on the NHS) to a patient or not. Meaning people (largely) pay privately for acupuncture etc but get evidence based care for for free.

CaulfieldTim22 karma

Short answer: yep. NICE does great work. Canada struggles as our system not as unified. So making allocation/assessment decision can be tough... need to involve all the provinces. This could be the topic of a PhD!!

AHLondon9 karma

Actually can make the case that public body makes it easier for shysters because only one entity to hoodwink. Witness homeopathy is available though the NHS. I think NICE is reviewing it again, but it's currently an approved prescription.

CaulfieldTim9 karma

Very interesting point! Hmmm... There have been recent reports from UK (further debunking). Here is a piece from Guardian on UK situation Like this quote: "If magical thinking is allowed into one corner of medicine, how are doctors supposed to root it out in other contexts?"

bumbadeen16 karma

If there was one change you would suggest making to your diet in order to promote a healthy body and mind, what would it be?

CaulfieldTim24 karma

Great question! I'd say eat more fruit & veggies. I aim for 1/2 of my daily plate. Some interesting emerging research demos value of good diet to mental health. Note: no super food!

bumbadeen6 karma

thanks! I have upped my fruit intake and am working on veggies...i'd read that a good diet (and exercise) can help deal with anxiety, attention issues, and so forth.

CaulfieldTim11 karma

For sure! Exercise one of the best things you can do. Might find this review of diet and mental health useful

bettyzou15 karma

Hi Tim! First off, just wanted to say that after reading The Cure for Everything, I recommended it to just about everyone I know. Thank you for all your work in debunking pseudoscience and health myths.

My question is: how do you handle social situations where a family member or friend is raving about the benefits of the latest cleanse/superfood/diet/etc...?

I often find myself in situations like this where I'd like to counter their claims with science but don't want to be mean and make them anyone look stupid. Any tips on how to best deal with a situation like that?

CaulfieldTim28 karma

Thanks for shout out! Thrilled you enjoyed The Cure.

Very good question! As you can imagine, this happens to me a lot. I can sense my family sending psychic messages. "Let it go, Dad!"

I think it is possible to respectfully engage. If they are just telling me about something they are doing, I let it go. But if they want to talk about it, I think it is important to mention the evidence. Sometimes I suggest a good study or review paper, noting that I'm glad [whatever they are doing] helps them... For me, it is important to keep science as part of the conversation.

soleilla9 karma

What do you think of the hunger strike by 68 inmates in Saskatchewan—should people and inmates have a right to healthy food like fruit and vegetables?

CaulfieldTim19 karma

Won't comment on how appropriate the strike is... but access to healthy food key.. especially fruits and vegetables. Should be core part of any nutrition policy. Yes?

emilianodc8 karma

Hi Tim, what do you think are the most relevant challenges from a scientific and a policy points of view with respect to direct-to-consumer genetic testing?

CaulfieldTim9 karma

Fascinated by this topic. I think we need more work on – and profile – around the impact of genetic risk information and behaviour change. There is good work on point (I tough on some of it here: Still, many of these companies are based on the idea that people will change behaviour. Currently, little evidence to support this view.

TummyDrums8 karma

What is your take on GMOs and how they affect our health?

CaulfieldTim19 karma

There is a strong consensus in the scientific community that GMO foods are not unhealthy. That is, there are no risks associated with the consumption of GMO foods. Take a look at this recent survey of the US scientific community BUT the public is concerned. In fact, this is the area with the biggest difference between the views of scientists and the public. To be clear, there are other issues associated with GMOs (corporate ownership, etc)...

Tim5417 karma

Many people follow the healthy lifestyle but truth is one day everything get fade away. Why we can't live forever?

CaulfieldTim15 karma

So true! This is often left out of the discussion. Yep, we are all gonna die. Quality of life should be a big focus, obviously. And a healthy lifestyle helps. Here is a grim graphic on causes of death in each age group

kittenjeju8 karma


CaulfieldTim13 karma

Interesting topic. Lots of cool research on point. But also need to watch for "telomere hype"!

clonegreen7 karma

Are there any supplements that you've found to be useful?

How about probiotics? Are they worth using?

CaulfieldTim10 karma

Personally, I don't take any [note: not offering clinical advice!]. I am not convinced by the existing data and most longterm studies show little benefit. As noted, vitamin D evolving. Many clinicians/researcher think supplementation valuable. Others suggest don't. I'm willing to be convinced!

Probiotics... another interesting topic! Lots of research on point. But lots of hype too. I'm skeptical of commercial products, but there is value for certain conditions. Some articles on point and

Due to all the attention on microbiome, I think we will be hearing more about this! Here is a really good article on gut hype!

LordofMylar7 karma

What are your top 5 favorite myths to debunk?

CaulfieldTim26 karma

Hmmm... so many to pick from. Off the top of my head: 1) Homeopathy (total bunk); 2) Cleanses/detoxes; 3) idea of spot reduction (that ab flex thingy will not give you sexy abs!); 4) the entire beauty industry (ok, that is too harsh); and 5) and vaccines cause autism (no, no, no). Ask me tomorrow and I'll have 4 different answers... #5 stays cuz it is so maddening, harmful and science-free.

andywhatever7 karma

was Dr Califf the right choice for FDA commissioner? easy to attack paltrow (i know nothing about her claims) but what about big pharma?

CaulfieldTim6 karma

I am very sensitive to the issues around Big Pharma. We have done a lot of research on the commercialization of research, for example. Here is a short piece on the issue Also, so many forces twisting science. In a piece I wrote with Celeste Condit we called it a hype pipeline... Publication pressure, career pressure, grant pressure, commercialization pressure, etc etc And they media twists more. See So, for sure, must be sensitive to all the forces that can distort what we hear about science and our health! What we need is more good, independent research! Onward science.

rishi136 karma

What are your favourate movies ?

CaulfieldTim14 karma

Movies! Too many to list! 2001 a space odyssey, Pulp Fiction, The Incredibles...

mikesherm6 karma

Yes! I love this kind of thing.

First, what's the scoop on if cholesterol actually leads to heart disease? Second, why are fruits and veggies actually healthy if vitamins/antioxidants seem to have their positive effects exaggerated?

Thanks so much for doing this!

CaulfieldTim4 karma

Timely question! New US nutrition guidelines out today "Most notable among the changes, the government dropped its warning about avoiding cholesterol in the diet."

The difference between fruits and veggies and pills is that the whole food has more to offer (fibre, etc)... Hard to isolate the good bits. Also, don't forget quality of supplements often an issue. See, for example,

rishi135 karma

Do you find some unknown facts ? Or some wrong miths during your research ?

CaulfieldTim14 karma

So many clearly wrong myths out there. Some endure despite the evidence (like the idea we are suppose to drink 8 glasses of water a day... nah). I think it is important to look at both evidence and scientific plausibility (e.g., homeopathy lacks plausibility). It is tough to do good research on some of these issues. No funding. Robust clinical trials not possible, etc. So often the data isn’t there. But it is also important to keep an open mind! Easy to get trapped by your own biases…

UCDWaffle5 karma

Wait we don't have to drink that much water a day? Is there an amount that is recommended?

CaulfieldTim8 karma

Easy: drink when you are thirsty! Nice piece by Aaron Carroll on water myth

rkk25 karma

Would it be possible to meet my daily recommended amount of nutrients by replacing all my meals with supplements and vitamins? If I were to do this what would happen to me?

CaulfieldTim18 karma

Sounds like a movie idea! "Super Supplement Me."

I'd say no. As noted early, food is complicated stuff. And we evolved to eat real food. You would be missing out on fibre and healthy aspects of, for example, an apple. Plus, it sure wouldn't be fun! Here is an interesting piece on point

turbonegro810635 karma

Do you think your brother Holden was a little rich kid brat?

CaulfieldTim5 karma

Just re-read. Not a brat, but seriously confused!

splitSeconds4 karma

What are your thoughts on e-cigarettes/vaping when it comes to comparison between the scientific literature and media reports?

CaulfieldTim8 karma

Seriously challenging health policy issue! We talked about this in my class yesterday. Here is a link to a terrific CBC show on point "Spin, Science and E-Cigarettes" I sympathize with the idea that they are likely much less harmful than cigarettes (though we need more research). That is a good thing. But I worry about the marketing to kids and the re-normalization of smoking (again, more data needed).

TheShadowCat4 karma

What do you see as the most dangerous health myth?

CaulfieldTim7 karma

Tough to pick one . And many of the myths have a broad, less direct, social impact (such as our emphasis on appearance over health). But the myths associated with vaccinations are truly frustrating and are having a clear adverse impact on human health.

gerihalliwellfan4 karma

Some people seem to avoid milk & dairy products due to some studies indicating a link between dairy consumption and acne. Are you convinced of such a connection? Do you have some other dietary advice for people suffering from acne?

CaulfieldTim8 karma

I'm mild agnostic! Don't think it is a miracle and often oversold (for a bunch of reasons). But not sure it is evil either. Walter Willett's team at Harvard has written some good stuff on point.

Tim5413 karma

Best meal for keeping your eyes healthy? I use glasses because my eyes sight is weak and now when i remove them i couldn't able to see anything clear. Can i fix it without any surgery ?

CaulfieldTim9 karma

I haven't done work on this topic specifically. But, in general, a healthy diet (no magical food) is likely the best approach (see, for example, So, a good diet won't fix bad eye sight (unless a specific, severe deficiency), but it will help keep them healthy!

LickItAndSpreddit3 karma

Hello Mr. Caulfield.

Not really a celebrity thing, and not something I would consider "noise," but it seems like gut health is still something that hasn't gained significant traction. i.e. the pivotal role that the gut microbiome has on immunity and general health.

Is this just a period of "growth" where it is being investigated to be more widely understood?

e.g. irritable bowel syndrome seems to be something that gastro doctors still regard as a "tough $#!+" problem where they treat the symptoms, while people who have targeted flushing/cleansing, and then re-building their gut flora have had huge successes.

CaulfieldTim4 karma

Good Q! I just noted this area in response to another question. Lots of exciting research going on in this area. Relevant to much.. from mood to obesity. In fact, for my last book I had my gut (read: fecal matter!) tested. And, as you may know, fecal transplants are used for some severe gut infections. Having said that, we are still early days... Relationship complex. Little evidence you can use a cleanse to create sustainable change in your gut biome. See this paper

anarkist2 karma

Does coffee increase or decrease the chance of developing cancer?

CaulfieldTim7 karma

I have a profound bias when it comes to coffee. Over-priced espresso is one of my favourite things! Still, lots of evidence that coffee is probably not bad for you and may even be good for you... see

hancysam192 karma

Which foods helps in boosting our immunity? And what are the side effects of using high dose protein supplements (for gym club)?

CaulfieldTim5 karma

I hear the immune boost question a lot. In fact, once again, no magic! I wrote a short piece on point Here is my conclusion "What is the best way to ensure your immune system is working well? Take care of yourself. [Warning: “Duh” prompt forthcoming.] And this means don’t smoke, get enough sleep, eat a healthy diet and exercise. It also means doing one of the few interventions that does help you immune system fight pathogens: get a flu shot." Once again, some interesting research around vitamin D, but still emerging...