Dr. Matthew Nagra, ND

11/21/2025

Does protein cause cancer by increasing IGF-1? Some advocates of low protein diets seem to think so, but the evidence doesn’t appear to be on their side.

Watch or listen to the full episode of with on your favourite podcasting app or .

Link in bio

References:
https://onlinelibrary.wiley.com/doi/10.1002/cam4.3345
https://pubmed.ncbi.nlm.nih.gov/31431306/
https://pubmed.ncbi.nlm.nih.gov/19746296/

Full episode: https://drmatthewnagra.com/the-proof-with-simon-hill-ep-390-the-protein-debate-is-over/

11/19/2025

Collagen is a very popular animal protein these days, but it’s actually incomplete (completely missing the amino acid, tryptophan) and does not stimulate muscle protein synthesis nearly as much as pea protein.

While we don’t have direct comparisons between collagen and plant proteins for actual muscle gains, we do see that collagen falls short of whey, while pea protein can match whey protein. So given all this information, it’s likely that pea protein (and others like soy protein) are superior to collagen for building muscle.

References:
https://pubmed.ncbi.nlm.nih.gov/38762187/
https://pubmed.ncbi.nlm.nih.gov/35042187/
https://pubmed.ncbi.nlm.nih.gov/38999765/

11/17/2025

Did you know that the genetic influence on weight may be as high as 70%! Twin studies suggest it’s anywhere from 40 to 70%, which further supports that obesity is not simply caused by a lack of willpower as some will suggest.

See the full debate on ’s channel! (Link also in bio) https://youtu.be/Pi1yLEltiy0?si=grkaVge2PHcdNQoU

11/14/2025

So is making stuff up again. He’s claiming that there are 7000 studies on a ketogenic diet with 2000 them of them being RCTs, with the majority supporting benefits. Well, there are only 499 total studies (excluding reviews) and 220 RCTs on Pubmed. Even if a Pubmed search doesn’t capture all of the available studies, you aren’t going to find thousands of additional studies. So yea… he’s making stuff up.
 

11/13/2025

Did you catch my appearance on ’s latest episode?

Here’s a clip on whether using Ozempic (or other GLP1RAs) is taking “the easy way out.” Watch the full episode on !

Link in my bio

https://youtu.be/Pi1yLEltiy0?si=tdOH0zE75fuBjzFq

11/12/2025

I recently participated in a debate on the topic of GLP1 receptor agonist medications like Ozempic, hosted by Jubilee. The episode just dropped this morning and you can watch it here:

I had the pleasure of participating in a debate on one of the hottest topics in the health and wellness ... Read More

11/12/2025

Plant protein is king when it comes to healthy aging!

Watch or listen to the full episode of with on your favourite podcasting app or !

Link in bio

Reference: https://pubmed.ncbi.nlm.nih.gov/38309825/

11/10/2025

I sat down with Simon Hill once again to discuss everything PROTEIN!

We tackle the debate over how much protein is optimal, whether plant protein can stack up to animal protein, and highlight which protein sources are healthiest.

Enjoy!

I joined Simon Hill to update our previous podcast episode on protein and to tackle some claims made by the ... Read More

11/10/2025

First off, plant-based meals have been shown to increase our endogenous GLP1 levels more than meat-based meals in multiple randomized crossover trials, in part due to the fibre content. Of course, won’t mention that. But that’s beside the point.

It doesn’t matter. The GLP1 that we produce ourselves has a half-life of about 2 minutes, meaning that levels rise and then fall back down really quickly. So these short-term boosts in GLP1 aren’t going to contribute to anywhere near the weight loss we see with the GLP1RA medications like Ozempic, since their half-life is about a week (hence the weekly dosing of the newer drugs). In fact, studies on medications that raise our endogenous GLP1 levels, which is short-lived, have not found that they contribute to weight loss, and ironically, sometimes the placebo group does better.

So to sum up: plant-rich meals lead to a greater boost in GLP1 than meat-based meals, but that’s largely irrelevant because no food or “GLP1 boosting supplement” comes anywhere even close to the impact of these medications. And from what I’ve seen online, a lot of people in the fitness or supplement space are threatened by that reality.

PS. Neither I nor Paul know anything about ’ medical or health history, so who are we to comment on whether these medications are indicated for her?

References:
https://pubmed.ncbi.nlm.nih.gov/30813546/
https://pubmed.ncbi.nlm.nih.gov/30642053/
https://journals.physiology.org/doi/full/10.1152/physrev.00034.2006
https://pubmed.ncbi.nlm.nih.gov/29915923/
https://www.cochranelibrary.com/cdsr/doi/10.1002/14651858.CD006739.pub2/full

11/07/2025

This is a sad example of someone who likely avoided medication and got duped into following a carnivore diet by influencers. Of course, he lost a lot of weight, which is the type of shorter-term result that carnivore influencers often promote, but he did mention a family history of heart disease and a history of high LDL-c levels both during and prior to the carnivore diet in the full video. And he isn’t the only example like this. There are plenty of stories of carnivores who ended up with coronary artery disease or strokes, but they just don’t get much attention from the pro-carnivore crowd.

But rather than diving back into concerns with a high red meat or saturated fat intake, which I’ve done plenty of before, I want to touch on how individuals like him are victims.

He is obviously confused, and rather than talking to his doctor, he’s turning to social media for advice after having a heart attack. Let that sink in… I even commented and suggested not to seek advice from social media, but rather to speak with his doctor and consider working with a dietitian, to which he replied that not all doctors agree on the benefits of things like statins, so he wanted to poll TikTok. Let’s be clear, there is consensus around the benefits of statins. There are just a handful of loud voices on social media that make it look like there’s debate. You won’t see that debate in medical guidelines.

If I had to wager, his doctor probably previously recommended cholesterol-lowering medication given his history of high LDL-c, but because of misinformation, he’s skeptical and was probably convinced by influencers that a carnivore diet would be his best bet. So he really exemplifies why medical or nutrition misinformation can be so dangerous and he’s far from the only victim of that misinformation.

References:
https://jamanetwork.com/journals/jamacardiology/fullarticle/2793729
https://jamanetwork.com/journals/jama/fullarticle/2618621
https://www.jacc.org/doi/10.1016/j.jacc.2018.11.003

11/05/2025

Carnivore, Anthony Chaffee is wrong again. For starters, they didn’t look at studies that the IARC left out because “they didn’t want to look at them.” There have just been some studies published since the IARC published their report in 2015, so there may be a few that IARC didn’t have at the time.

But what’s even more comical is that he claims they looked at over 800 studies. Nope. They looked at 20 cohorts (observational studies that he usually claims are garbage)… The IARC, on the other hand, did look at over 800 studies for their publication back in 2015.
 
Further, he claims that, in the Burden of Proof study, they didn’t even find an association between processed meat and cancer… but again they didn’t even look at processed meat in the paper he shared. In fact, he literally read out the title that says “unprocessed red meat.” Although, they did publish a paper looking at processed meat later on that did identify an association between processed meat and colorectal cancer.

But going back to unprocessed red meat, in the paper he shared, each 100g/day was associated with a 37% higher risk of colorectal cancer. But due to some very odd methodology that has been criticized in additional publications, they downplayed that to suggest it’s a “weak” association. The Burden of Proof group also found that smoking only has a “weak” association with oral cancers and secondhand smoke has “weak” associations with heart disease and lung or airway cancers. This just further suggests that how they rated evidence in these studies is odd, and if he’s going to accept that red meat data, then he kind of has to accept their bizarre smoking findings.

References:
https://www.nature.com/articles/s41591-022-01968-z
https://www.thelancet.com/journals/lanonc/article/PIIS1470-2045(15)00444-1/fulltext
https://www.nature.com/articles/s41591-025-03775-8
https://www.nature.com/articles/s41591-023-02294-8
https://www.nature.com/articles/s41591-022-01978-x
https://www.nature.com/articles/s41591-023-02743-4

11/03/2025

claims that HALF of the weight loss on GLP1 medications like Ozempic is muscle mass! This is plain false.

Based on randomized controlled trials, these medications result in about 40% lean mass loss, which includes muscle mass AND “water weight” and other tissues. Only about half of that is muscle mass, so these medications, on average, result in about 60% fat loss, 20% muscle loss, and 20% loss of other mass (eg. “water weight”). This is similar to the muscle loss that occurs with significantly cutting calories WITHOUT medication. When you lose weight, some of it will be muscle loss, but the hope is that most of it is fat loss, which is the case with these medications.

However, those numbers I cited are WITHOUT resistance training. Engaging in weightlifting or bodyweight exercises can help to preserve muscle. Also, it’s worth noting that, even without advising for resistance training, the use of these medications can lower the risk of major cardiovascular events like heart attacks and strokes by 13%, kidney failure by 9%, and all-cause mortality, the risk of dying during the first ~2.4 years on these medications, by 12% based on a systematic review and meta-analysis of 21 trials and about 100,000 people.

Finally, we have now seen reductions in obesity prevalence in the USA 3 years in a row after what was almost year-after-year increases in obesity for the past few decades. These medications are working in a way that no diet trend ever did. Let’s celebrate the fact that we have such an amazing tool and not fear-monger over or exaggerate the muscle loss or other adverse effects.

References:
https://www.sciencedirect.com/science/article/pii/S0002916525002400?via%3Dihub
https://pubmed.ncbi.nlm.nih.gov/37807154/
https://pubmed.ncbi.nlm.nih.gov/40892610/
https://news.gallup.com/poll/696599/obesity-rate-declining.aspx