What Happens to Your Body on a Sardine Fast? | Dr. Dominic D’Agostino

Jesse Chappus (0:00)

Coming up on today's show.

Dr. Dominic D'Agostino (0:02)

A sardine fast, 500 to 600 calories per day for three days, has done remarkable things to my blood biomarkers of cardio metabolic health. And if someone wants to research this a little bit more, they could research fasting mimicking diets on PubMed, and you'll find a lot of information about the benefits, not only during the time that you're doing it, but even a month or two months after a five day fast. The people that communicate with me are doing it to manage a particular disorder, whether that's insulin resistance, type 2 diabetes, cancer. I like the idea of using this particular food because of the protein quality, the protein quantity hits it, so you're not protein restricted. And also the omega-3 fatty acids have an anti-catabolic effect and an anti-inflammatory effect. A can of sardines with apple cider vinegar and MCT oil is kind of like a GLP-1. I'm telling you, the data backs it up, putting your body into a state of ketosis with super high omega-3 nutrient dense food that puts you into a calorie restriction state is very beneficial for the brain on so many levels, especially during periods of stress. Can't really find too many foods superior to sardines. I challenge people to do that. I've done a deep dive on this.

Jesse Chappus (1:20)

Dom, you've experimented with something called a sardine fast. What exactly is that and why sardines?

Dr. Dominic D'Agostino (1:27)

Okay, coming right out of the gate with the sardine. Okay, questions, yes.

Well, there's a bit of a history behind doing that.

And I would probably default to my experience with a cancer patient. His name was Dr. Fred Hatfield, also known as Dr. Squat. And I had been turned on to sardines by a book. It was called, you know, it was a red book. I remember it was just like The Power of Sardines or something. And I read that and I think it was about 2006 or 2007 I, instead of tuna fish, I started trying sardines and I gradually shifted over. Just, you know, researching the heavy metals because I was eating so much tuna. And I was, I was worried about tuna. Tuna is very convenient, especially when you're in the lab and you don't have time. So, so over the years, I kind of gravitated towards doing more keto, intermittent fasting, and stumbled upon using sardines during that time. And it had a very pretty pronounced appetite suppressing effect. So if, if ever I was doing a calorie restricted ketogenic diet, that worked really well. And I advised a cancer patient to do it. And during his time of doing it, he went into remission with his cancer. And that left the lasting impression on me.

The particular individual was a spiritual mentor to me, and is sort of, and also a mentor and, you know, working out and things like that. So that kind of left an impression on me. So over the years, I just kind of gravitated towards being a sardine enthusiast, I guess you could say, and somehow it got, it got picked up on the algorithm. When I was on Tim Ferriss' podcast.

Jesse Chappus (3:17)

So let's talk about metabolically, when somebody is on sardines versus keto, or water only fasting, the difference there.

Dr. Dominic D'Agostino (3:26)

Okay, well, I like to clarify that it does not have to be sardines necessarily to get the benefits. And more recently, I've been using mackerel, chub mackerel in particular, not king mackerel, which could have higher levels of heavy metals. I buy like a 14 or 16 ounce can, it's cheaper. I was giving it to my dogs. And so the advantage of sardines, kind of like eggs too, I guess you could say, is that it's almost like a food that has all the nutritional requirements that you would need. One might say it has, you know, maybe high in purines and that could lead to gout, or, you know, or it's deficient in vitamin C or something like that. But when we're talking about sardine fast, we're not talking about eating sardines and only sardines for protracted period of time, right? So if one is to embrace the sort of idea of a fasting-mimicking diet, which has been advanced by Dr. Valter Longo, and I do have a lot of respect for Dr. Longo, although he's a little bit on the protein restriction end.

I think a sardine fast 500 to 600 calories per day of sardines for three days has done remarkable things to my blood biomarkers of cardiometabolic health. And if I go beyond that, it tends to reduce like hormone levels. I see it in my T3, I see it in my testosterone. So I've done a lot of fasting dating back 15, 20 years. And the three-day fast is a great metabolic reset for me. I tend to do it when I'm traveling.